Digest for sci.electronics.repair@googlegroups.com - 25 updates in 5 topics

John Robertson <spam@flippers.com>: Feb 28 10:37PM -0800

>> the picture shifts sideways until it loses the lock.
 
>> John :-#(#
 
> I wonder if you're describing what we used to call "piecrusting". Most of that was was from leaking HV. Remove the HV rectifier and see if there's any green schmutz in the contacts. Any corrosion will cause arcing.
 
Sorry, been busy. The diode is soldered directly to the HV leads. So a
bad connection is out. The HV probe does not show any obvious signs of
jitter, but I suspect that would be the case seeing as the tube is a
giant capacitor and would smooth over most noise.
 
I also pulled the LOPT/Flyback and did both a ring test and a leakage
test - it passed both just fine, good ring count, and no appreciable
leakage using my old Heathkit R/L/C Bridge Cap checker (1960s - with
Magic Eye tube!).
 
Additional comments in response to other posts on this topic...
 
Thanks,
 
John :-#)#
 
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
John Robertson <spam@flippers.com>: Feb 28 10:53PM -0800

On 2017/02/27 8:59 AM, Chuck wrote:
 
> ---
> This email has been checked for viruses by Avast antivirus software.
> https://www.avast.com/antivirus
 
Hi Chuck,
 
Thanks for the suggestions - I tried all that and no improvement in the
image quality. I used a couple of 1N43 Germanium diodes in place of the
AA143s, but (as I said) no change.
 
The only place I can 'see' a problem is when I monitor the cathode of
the picture tube. The horizontal section appears quite stable with no
flicker showing on my fast Tectronics scope.
 
Images:
 
Video - jitter on screen:
 
http://www.flippers.com/images/Horizontal_jitter_on_TEC_monitor.MOV
 
Scope - base of Horizontal drive:
 
http://www.flippers.com/images/Horizontal-drive-@-base
 
Scope - base of final video amp:
 
http://www.flippers.com/images/Base_of_final_video_amp
 
Schematic - base of final video amp (wrong version of schematic here
though):
 
http://www.flippers.com/images/Base_of_final_video_amp-scope
 
Appreciate any other suggestions. I haven't yet tried replacing the
resistors in the feedback loop, however the jitter doesn't show in the
loop...
 
Thanks!
 
John :-#)#
 
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
Phil Allison <pallison49@gmail.com>: Feb 28 03:17PM -0800

Michael Terrell wrote:
 
> > EL34s can also be used the same way to deliver 100W.
 
> > Guitar amps made by MusicMan and Dynacord are commercial examples.
 
> He asked about the 6L6,
 
** The OP asked about "common audio output tubes" which the original 6L6 is not.
 
It's an all metal, museum piece.
 
6L6GCs have been the most common type sold for audio use for decades.
 

 
 
.... Phil
"Michael A. Terrell" <mike.terrell@earthlink.net>: Feb 28 07:39PM -0500

Phil Allison wrote:
 
> ** The OP asked about "common audio output tubes" which the original 6L6 is not.
 
> It's an all metal, museum piece.
 
> 6L6GCs have been the most common type sold for audio use for decades.
 
 
 
Yes, but the 'Amateur radio transmitters' he's talking about are from
the '40s and '50s, which were shipped with the original metal 6L6, not
the later glass versions. A lot of them were built with W.W. II surplus
tubes, of which the 6L6 was readily available as surplus into the '70s.
 
We aren't talking about stereos or guitar amps. The were audio
outputs for radios, or modulators for medium power AM transmitters
designed for Amateur radio service. I was servicing these radios back in
the '70s. That is four decades ago.
 
 
--
Never piss off an Engineer!
 
They don't get mad.
 
They don't get even.
 
They go for over unity! ;-)
Phil Allison <pallison49@gmail.com>: Feb 28 06:08PM -0800

Michael Terrell wrote:
 
> Yes, but the 'Amateur radio transmitters' he's talking about are from
> the '40s and '50s, which were shipped with the original metal 6L6, not
> the later glass versions.
 
 
 
** Read correctly, the OP was not asking about transmitters at all.
 
The performance of some common tubes for audio output use was his topic.
 
 
 
.... Phil
"Michael A. Terrell" <mike.terrell@earthlink.net>: Mar 01 12:26AM -0500

Phil Allison wrote:
>> the later glass versions.
 
> ** Read correctly, the OP was not asking about transmitters at all.
 
> The performance of some common tubes for audio output use was his topic.
 
QUOTE:
 
I was looking at some old 813 tubes that were once commonly used for
Amateur radio transmitters, as the final output tube. While the common
audio output tubes like 6L6 and 807 can produce about 25 to 30 watts
audio output (per tube), running around 300 to 450 volts plate voltage,
 
UNQUOTE:
 
--
Never piss off an Engineer!
 
They don't get mad.
 
They don't get even.
 
They go for over unity! ;-)
Clifford Heath <no.spam@please.net>: Mar 01 05:18PM +1100

On 01/03/17 16:26, Michael A. Terrell wrote:
> audio output tubes like 6L6 and 807 can produce about 25 to 30 watts
> audio output (per tube), running around 300 to 450 volts plate voltage,
 
> UNQUOTE:
 
So you agree, OP was not asking about transmitters?
He also wasn't asking about 6L6's of either type!
(though his reference to 30W/tube says he meant 6L6GC).
 
He was asking about 813 (transmitting) tubes in an audio amp.
 
Phil was right. Now can we please end this pissing match?
micky <NONONOmisc07@bigfoot.com>: Feb 28 02:40PM -0500

In sci.electronics.repair, on Tue, 28 Feb 2017 05:15:08 +0000 (UTC),
>signal from -100 dBm to -50dBm at home using these three free devices from
>the carrier:
>http://i.cubeupload.com/sSOph0.jpg
 
These seem to be for LTE.
 
>I used my Android phone to check exactly which of the three devices worked
>best to give me the best cellular signal strength:
>http://i.cubeupload.com/HIz95n.jpg
 
I like this meter. Does it only measure HSPA? If it measures others
too, can I install it on my phone? What is it called.
 
 
>The three devices are two different types, where this one is a pure
>cellular signal booster (the other ties to your router):
>http://i.cubeupload.com/NhwUFR.jpg
 
They also seem to be for LTE??
Stijn De Jong <stijndekonlng@nlnet.nl>: Feb 28 08:38PM

On Tue, 28 Feb 2017 14:40:32 -0500, micky wrote:
 
>>the carrier:
>>http://i.cubeupload.com/sSOph0.jpg
 
> These seem to be for LTE.
 
When I complained to T-Mobile that my cell signal was around -105 dBm, they
sent me the signal booster, which recently died in all the power outages
we've been having, so they sent me a second signal booster and what people
seem to call a femtocell that connects to the router.
 
They all seem to be labeled "LTE":
https://u.cubeupload.com/sSOph0.jpg
 
>>http://i.cubeupload.com/HIz95n.jpg
 
> I like this meter. Does it only measure HSPA? If it measures others
> too, can I install it on my phone? What is it called.
 
I think it measures everything found in the USA.
You can refer to this thread for the tools used.
From: Stijn De Jong <stijndekoning@nlnet.nl>
Newsgroups: comp.mobile.android,misc.phone.mobile.iphone
Subject: Which app do you use to scan/debug GSM/CDMA cellular tower
signal strength?
Date: Thu, 16 Feb 2017 01:52:24 +0000 (UTC)
Message-ID: <o830kn$bvh$1@gioia.aioe.org>
 
If you put that message id into this site, it should pop up:
http://al.howardknight.net/
 
You can find the entire thread here:
https://groups.google.com/forum/#!forum/alt.home.repair
 
Which reports this URL which contains scores of screenshots and
recommendations for both Android and iOS devices.
 
https://groups.google.com/d/msg/comp.mobile.android/PC0ePLqaD5w/HoH7HiLsBwAJ
 
The goal is for each user to improve upon the tribal knowledge of all.
Stijn De Jong <stijndekonlng@nlnet.nl>: Feb 28 08:51PM

On Tue, 28 Feb 2017 20:38:14 +0000 (UTC), Stijn De Jong wrote:
 
> You can find the entire thread here:
> https://groups.google.com/forum/#!forum/alt.home.repair
 
My mistake.
 
That was the wrong search url as it was for alt.home.repair:
https://groups.google.com/forum/#!forum/alt.home.repair
 
This is the right url for Android:
https://groups.google.com/forum/#!forum/comp.mobile.android
 
While we're at it, this is the right url for iPad:
https://groups.google.com/forum/#!forum/comp.mobile.ipad
 
And this is the right url for iphones:
https://groups.google.com/forum/#!forum/misc.phone.mobile.iphone
 
You'll find probably a hundred very detailed screenshots in that thread.
For example, here are the dramatic results of just one experiment!
 
http://i.cubeupload.com/jqV5cR.jpg
 
Without the tools, it's hard to tell exactly which device is doing what:
http://i.cubeupload.com/RLxLv5.jpg
Stijn De Jong <stijndekonlng@nlnet.nl>: Feb 28 09:02PM

On Tue, 28 Feb 2017 14:40:32 -0500, micky wrote:
 
>>cellular signal booster (the other ties to your router):
>>http://i.cubeupload.com/NhwUFR.jpg
 
> They also seem to be for LTE??
 
I'm ignorant of what acronym should I be looking for?
 
I must confess that I'm not sure what the significance of your question
about LTE is, but mostly because I'm pretty ignorant of the various
acronyms (EDGE, HSPE, LTE, etc.) even though I see them on my phone at
times.
 
All I know is I asked T-Mobile for better cellular signal (I don't really
do data on the phone except on WiFi). They gave me these three devices.
https://u.cubeupload.com/sSOph0.jpg
 
They're all labeled "LTE" but I don't really know what to make of that
since they all seem to give me better signal strength in different ways.
http://i.cubeupload.com/RU3rGl.jpg
 
What I find most useful is that I went from -100dBm to -50dBm, which is a
jump of about half a million times stronger signal.
http://i.cubeupload.com/RUsTGy.jpg
 
Note that -50dBm is about as good as is humanly possible even if you were
standing right in front of a cellular tower.
 
If someone can give me a quick rundown on what acronyms are important in
this endeavor, I'd appreciate it.
 
Remember, I only asked for them to increase my "cellular signal".
I didn't ask for LTE (and I don't use cellular data to any extent).
 
This survey, for example, at my house, says UMTS (whatever that means):
http://i.cubeupload.com/3y52PN.jpg
 
Yet, this survey, again in the same location, says HSPA (whatever that's
telling me):
http://i.cubeupload.com/tLTJFw.jpg
 
So does this survey in the same location:
http://i.cubeupload.com/9MCM5S.jpg
 
And this one too:
http://i.cubeupload.com/WA3BwE.jpg
 
Yet, this survey, same place, just says GSM/CDMA:
http://i.cubeupload.com/U1aqb7.jpg
 
I admit I really don't understand what these acrynyms are trying to tell me
since my own surveys shown above show an alphabet soup of acronyms at
various times in my tests.
 
What should I be concluding from all these acrynyms at my one location?
micky <NONONOmisc07@bigfoot.com>: Mar 01 12:48AM -0500

In sci.electronics.repair, on Tue, 28 Feb 2017 20:38:14 +0000 (UTC),
>signal strength?
> Date: Thu, 16 Feb 2017 01:52:24 +0000 (UTC)
> Message-ID: <o830kn$bvh$1@gioia.aioe.org>
 
Great.
 
>If you put that message id into this site, it should pop up:
> http://al.howardknight.net/
 
I just searched on the subject in my list of posts (another advantage of
off-line readers.) Then I looked for the day an date.
 
>Which reports this URL which contains scores of screenshots and
>recommendations for both Android and iOS devices.
 
>https://groups.google.com/d/msg/comp.mobile.android/PC0ePLqaD5w/HoH7HiLsBwAJ
 
That sounds interesting too.
 
But from the post you referred me to, I found 4 that sound quite nice.
However I'm like a duck, and I like most whatever I have imprinted on,
so I'm startign with the one I looked at in this thread.
 
>The goal is for each user to improve upon the tribal knowledge of all.
 
I'll try to do my share.
 
I've only installed network Cell Info Lite and it has more information
that I can absorb. Phone and wifi. And it knows all about both sim
acrds etc.
 
And it has an FAQ *and* an online manual. Most apps I see don' thave
either. i have to guess at how they work.
 
On map, it has a red line that I t hought would point toward the tower,
but it points** towards a strictly residential area. There are two cell
towers right next to the supermarket I go to about 4 blocks away, I
figured one was mine, but it is ignoring both of them. Sometime I will
take the phone over there and see what it says.
 
**It was a long red line but the line got shorter and it added the image
of a tower, and there might actually be one there now. There wasn't a
few years ago It would only be 7 blocks from the one I know about.
Is't that closer than need be? At any rate, I'll go over there and
see. It's an apartment complex that might want extra money for
permitting a tower.
 
Thanks. P.s, this was so much fun I may not wait til tomorrow to get
a second one.
oldschool@tubes.com: Feb 28 02:24PM -0600

I said I would not order anything from China or anywhere outside of
North America. But I placed an order today for some chassis mount RCA
phone jacks, from China. Now I am sort of worried.....
 
I want to build a box so I can swap the output from my computer to
several amplifiers, and need at least 8 jacks. Radio Shack wants about
$6 for a pair of them, and they only had 2 packages (4 jacks) in the
store. I dont plan to make this thing for several weeks, because I have
other priorities, so I decided that I can wait a month or so for this
package to arrive from China.
 
I placed the order. 40 jacks for around $8 (with shipping). Cant argue
about that price....
 
After placing the order I was reading the fine print in the ad, and it
says "buyer is responsible for all Tariffs and Taxes....
This has me worried. Who will bill me for that? What percentage of the
price must I pay? I'd think on an $8 order it would only be a dollar or
less, but since this is government, they could charge me $100 or
more....
 
What's the scoop on this?
 
(If I had read this before placing the order, I would not have placed
this order).
JC <Chipbee40_SpamNo@yahoo.com>: Feb 28 03:44PM -0500


> What's the scoop on this?
 
> (If I had read this before placing the order, I would not have placed
> this order).
 
There are no import duty/taxes into the USA and the Chinese mark stuff
low value or gift usually. (Don't tell Trump)
ohger1s@gmail.com: Feb 28 01:16PM -0800


> What's the scoop on this?
 
> (If I had read this before placing the order, I would not have placed
> this order).
 
Don't worry about it. I've bought thousands of parts from China and never had to pay any duty or tariff.
 
But then, I don't think I've spent any more than $100 on any given order.
Wayne Chirnside <wc@faux.com>: Feb 28 09:50PM

On Tue, 28 Feb 2017 14:24:02 -0600, oldschool wrote:
 
 
> What's the scoop on this?
 
> (If I had read this before placing the order, I would not have placed
> this order).
 
I have used Banggod, Aliexpress and Gearbest and as yet no taxes or
tariffs on some 120 orders.
Ralph Mowery <rmowery28146@earthlink.net>: Feb 28 05:17PM -0500

In article <t9mbbc5418km67mllujvn066i1utpo7uma@4ax.com>,
oldschool@tubes.com says...
 
> What's the scoop on this?
 
> (If I had read this before placing the order, I would not have placed
> this order).
 
Don't worry aoburt it. I have ordered lots of things off Ebay from
China. Some parts and some circuit board assemblies. Most of the time
it takes about 3 weeks or so to get here. I did have one item that was
only about $ 8 including shipping that took about 2 1/2 months, but it
got here.
 
The taxes and whatever are in the price you see on Ebay. You will not
be charged mpore at a later date.
 
It amazes me how they have shipped in some items that only cost about $
2 or less. To get a 1 st class letter out of the US to another country
costs about $ 1.25. China does pick up the out going postage form what
I have heard.
 
So far everything I have ordered has met my expectations. Some
simiconductors dont. Friend ordered about $ 25 worth of transistors
(about 8 of them) and they were all bad.
 
While you are looking around on ebay look for a component tester. It is
a circuit board with a lcd display. It will have 3 leads and a 9 volt
battery terminal. They are usually less than $ 20 and will test about
anything you hook to it that will work at 9 volts or less. Best spent
money for testing I have ever seen.
Foxs Mercantile <jdangus@att.net>: Feb 28 04:53PM -0600


> What's the scoop on this?
 
> (If I had read this before placing the order, I would not have placed
> this order).
 
It's Lawyer speak" for cover your ass.
The only time I've had problems is buying stuff from Canada and using
UPS, where it went into a customs warehouse and customs wanted to rape
me on duty fees. Similarly sending stuff to England where the hose the
buyer with value added taxes.
 
I have had ZERO problems with buying stuff from China via eBay or
Aliexpress.
 
 
--
Jeff-1.0
wa6fwi
http://www.foxsmercantile.com
mike <ham789@netzero.net>: Feb 28 09:14PM -0800

On 2/28/2017 2:17 PM, Ralph Mowery wrote:
> got here.
 
> The taxes and whatever are in the price you see on Ebay. You will not
> be charged mpore at a later date.
 
Don't think that's accurate. They specifically say that they aren't
responsible. Last I looked, there was a limit for US duty free
in this type of transaction and it was
something like under $250. Who knows what Trump is gonna do.
 
> So far everything I have ordered has met my expectations. Some
> simiconductors dont. Friend ordered about $ 25 worth of transistors
> (about 8 of them) and they were all bad.
 
I've had very few EBAY items that were what I expected. Most just
failed to disclose...others outright misrepresented the product.
If the price is very low, it may still be worth it.
There are some really cost-effective products, like flashlights,
that are WELL short of specification, but still a great value.
I don't trust the specs posted for anything.
micky <NONONOmisc07@bigfoot.com>: Feb 28 02:50PM -0500

In sci.electronics.repair, on Mon, 27 Feb 2017 15:36:52 -0800, Jeff
>FET), 3Nxxxx = (Dual gate MOSFET), 4N = Optoisolator, etc. That
>lasted about 10 years before devices arrived that could not easily be
>crammed into the significant numbering scheme.
 
I agree with you here.
 
> The JEDEC would have
>been better off just starting at 00001 and counting up in sequence. It
 
I don't agree they would be better off. The system was valuable for
many early tubes and I didn't expect it to work forever. so I ignored it
when it didn't work. Numbers in sequence would have meant nothing,
 
OTOH, the relationship between a 6SD6 and a 12SD6 is clear. (I'm not
positive those exact tubes existed. It's been a long time.)
 
And the tubes in my father's battery powered tube radio, with names like
1au4 and 2-something, made it clear how they could run off of batteries.
(Unfortunately one of the batteries was iirc 46v, so I couldn't afford
to buy another one.) The radio also ran on AC, but was meant for civil
emergencies.
 
Someone, maybe my father, also bought a crystal radio, a 3-inch
diameter, 3/4" brown plastic box with holes in one side to listen
through, and a green wire with an alligator clip coming out of it. It
had a clear plastic rounded fluted tuning knob and only got one station
in Indianapolis, the strongest one I think. But one is enough, if we'd
ever been without power during an emergency. But I dont' think we ever
were.
 
>would seem that the semiconductor people had not learned the lessons
>of tube numbering, and repeated the basic mistakes.
 
As to 813 etc. I haven't found any all numerica names but I wouldn't
have thought the 8 referred to voltage. That I would have taken as some
subset of sequential numeric naming.
ohger1s@gmail.com: Feb 28 01:26PM -0800

On Tuesday, February 28, 2017 at 2:50:33 PM UTC-5, micky wrote:
 
> As to 813 etc. I haven't found any all numerica names but I wouldn't
> have thought the 8 referred to voltage. That I would have taken as some
> subset of sequential numeric naming.
 
I suspect the very early tubes were simply numbered in order of development. My old Radiola uses an 80, a 171 and a bunch of 27s. The 27s are 2.5v filaments and the 171 and 80 are 5v.
Foxs Mercantile <jdangus@att.net>: Feb 28 04:49PM -0600

In short, there is no "standard" numbering scheme for American
vacuum tubes.
 
In the "beginning" numbers 01 though 99 were assigned pretty
much on a "first come first serve" basis.
More confusing were, for example, adding a number to signify
manufacturer. For example, the type 27. 127, 227, 327, 427 etc
were the same tube but by different manufacturers.
 
Starting in the '30s, they got together and agreed that the
first number would be the filament voltage.
6A7 for example, 6.3 volt filament. 5Y3, 5 volts etc.
 
An original "idea" of assigning 1 or 2 letters in the middle
on a per function basis went to Hell surprisingly fast.
 
During WWII, the military also came up with VT-nnn numbers
that referenced "normal" tubes, such a 27, 80, 6SK7 etc.
 
Transmitting tubes were different, usually "high numbers"
such as the 807, 811, 813, 1625 and so forth.
 
Then there's the entire gambit of 4-digit "industrial" types.
Nominally in the 4000-9000 range.
 
The only other thing they agreed on was keeping the type the
same across different filament voltages. 6BE6 and 12BE6 as an
example.
 
Then of course, a few manufactures came up with their own
bastard numbers. Like Taylor TZ-40. "Taylor, Zero bias, 40
watts."
 
 
 
 
 
 
 
 
--
Jeff-1.0
wa6fwi
http://www.foxsmercantile.com
Ralph Mowery <rmowery28146@earthlink.net>: Feb 28 05:51PM -0500

In article <c7ef9132-3aab-4577-be9e-248896588a09@googlegroups.com>,
ohger1s@gmail.com says...
> > have thought the 8 referred to voltage. That I would have taken as some
> > subset of sequential numeric naming.
 
> I suspect the very early tubes were simply numbered in order of development. My old Radiola uses an 80, a 171 and a bunch of 27s. The 27s are 2.5v filaments and the 171 and 80 are 5v.
 
 
As with all things they start off with a sysem and as new items are
developed that system falls apart. I think tubes were numbered in order
to start with. Then they were listed as the first number being the
filiment voltage, letters to indicate what type and the last number the
number of elements.
 
Some power tubes started with a number a dash and another several
numbers such as a 3-500. That was the number of elements and the plate
dissaplation. A 4x150 started the same way. Later it was a 4cx150 that
indicated a ceramic seal instead of glass. Then a letter was added to
the end to indicate the filiment voltage.
 
Simiconductors tried the same system. First number the number of
junctions. Not sure about the N and the last numbers were just assigned
in order. Later some even had dots of colored paint on them This was
for the range of gain on them.
 
Japan tried the same thing with the numbers. One was the number of
junctions. leters for the type, RF , AF.
Many of them left off the starting 2 on them and yu just had to remember
to add that when looking at them.
John Robertson <spam@flippers.com>: Feb 28 03:38PM -0800

>> have thought the 8 referred to voltage. That I would have taken as some
>> subset of sequential numeric naming.
 
> I suspect the very early tubes were simply numbered in order of development. My old Radiola uses an 80, a 171 and a bunch of 27s. The 27s are 2.5v filaments and the 171 and 80 are 5v.
 
My 1933 RCA/Cunningham Radio Tube Manual agrees. Pg 143:
--------------------------------------------------------------
THE NEW TUBE-NUMBERING SYSTEM
 
Type numbers for new tubes are now being assigned in accordance with the
new system adopted in the early part of 1933 by the Radio Manufacturers
Association. A new system was required because practically all of the
available two and three digit numbers have been utilized.
 
... (description of the numbering system, as described above)
 
While these rules assist to some extent in classifying tubes by filament
voltage and function, the significance of the individual symbols will in
most cases be inadequate to identify the specific features of a tube.
--------------------------------------------------------------------
 
I love old manuals!
 
John :-#)#
 
--
(Please post followups or tech inquiries to the USENET newsgroup)
John's Jukes Ltd. 2343 Main St., Vancouver, BC, Canada V5T 3C9
(604)872-5757 or Fax 872-2010 (Pinballs, Jukes, Video Games)
www.flippers.com
"Old pinballers never die, they just flip out."
"Michael A. Terrell" <mike.terrell@earthlink.net>: Feb 28 07:42PM -0500

micky wrote:
 
> As to 813 etc. I haven't found any all numerica names but I wouldn't
> have thought the 8 referred to voltage. That I would have taken as
> some subset of sequential numeric naming.
 
 
The 813 is an industrial tube, not a consumer numbered tube.
 
 
--
Never piss off an Engineer!
 
They don't get mad.
 
They don't get even.
 
They go for over unity! ;-)
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Digest for sci.electronics.repair@googlegroups.com - 23 updates in 16 topics

Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>: Feb 28 10:34AM -0500


> And then there were those old 1B3 tubes in TV sets. Where did the 1 volt
> heater voltage come from? (and why didn't they just stick with 6.3 volts
> like other tubes?)
 
The heater winding needed very thick insulation, so it made sense to use
fewer turns with more copper.
 
> the numbers they get, or are they just random numbers given for no real
> reason? I wont even get into the IC chips and what leads to the
> number/letters used on them....
 
The 2N numbering system was from JEDEC, the US Joint Electron Device
Engineering (council, command, committee, conspiracy, C-something,
anyway). See e.g. <http://esartaj.tripod.com>.
 
> * If anyone knows of a COMPLETE listing that can be downloaded, such as
> a PDF file, please post the URL. (or even a text file). I am not finding
> anything that's complete......
 
You might look at <http://www.duncanamps.com/technical/tubenumber.html>
 
Cheers
 
Phil Hobbs
 
 
 
 
--
Dr Philip C D Hobbs
Principal Consultant
ElectroOptical Innovations LLC
Optics, Electro-optics, Photonics, Analog Electronics
 
160 North State Road #203
Briarcliff Manor NY 10510
 
hobbs at electrooptical dot net
http://electrooptical.net
N_Cook <diverse@tcp.co.uk>: Feb 28 03:05PM

On 26/02/2017 19:31, Gareth Magennis wrote:
> A simple LED shoved into the two pins either side of central will show
> all MIDI activity quite nicely.
 
> Gareth.
 
Appropriate timing response for "dead " key presses cf working adjascent
keys , in the signal lines, so will transfer my attention to
interpretation / output side of things
rickman <gnuarm@gmail.com>: Feb 23 01:49PM -0500

On 2/23/2017 5:50 AM, Spehro Pefhany wrote:
 
> Their argument was that it was a relatively large amount of money so I
> should lose half. If it was $5 or $10 they probably would have made
> the dishonest vendor pay 100%. So, caveat emptor.
 
That's so BS, but it may be a cultural thing. A friend was in a taxi in
Vietnam and a cyclist was hit. The two drivers started haggling and
bystanders joined in to mediate. In the end it was decided that the
cyclist should get $50. They said my friend should pay.
 
--
 
Rick C
Hul Tytus <ht@panix.com>: Feb 23 10:45PM

Try Jameco. They have a $20 minimum and sell a lot of "pulls" & odd stuff.
Almost all are "through hole" devices, which can be handy.
 
Hul
 
gregz <zekor@comcast.net>: Feb 24 08:56AM


> What (if any) online stores will fit my needs?
> Maybe its none of these huge stores, but something smaller...
 
> Thanks
 
My old list not updated.
 
http://www.pitt.edu/~szekeres/mail.htm
 
Greg
VanguardLH <V@nguard.LH>: Feb 24 02:16AM -0600

micky wrote:
 
> battery is dead would disarm alarms. So I was trapped in the house.
> Eventually I disconnected the control panel from the siren driver, so it
> didn't make any noise the next time.
 
Haven't a clue what is the hardware which you seem to deliberate omit in
your posts. Could be the code gets stored in EEPROM but I doubt it
since it would take sufficient voltage to reprogram the bits in the
chip. Could be there is a capacitor on the PCB used to hold the code.
That capacitor discharged long ago so any value stored in volatile
memory is gone. Could be a battery is used instead of a capacitor.
Just like your PC, a dead battery means the CMOS table's values (a copy
of the BIOS and where you do your tweaks, like changing a login
password) is corrupted or all values are unusable. That means the BIOS
copy of the settings get loaded into the CMOS table.
 
If it uses EEPROM, something is wrong with the hardware that had it lose
your stored code. If it uses a capacitor, well, those things only stay
charged for a limited time. If it uses a battery, replace it as it is
probably too old and doesn't have enough capacity (might have enough
voltage under a no-load test but cannot supply any current, even a tiny
bit, without a voltage drop).
micky <NONONOmisc07@bigfoot.com>: Feb 24 03:48AM -0500

In sci.electronics.repair, on Fri, 24 Feb 2017 02:16:25 -0600,
>> 30 y.o. oil furnace. That coudln't do it. A small tv in the room
>> too. There's a microwave upstairs.
 
>Haven't a clue what is the hardware which you seem to deliberate omit in
 
No, I didn't deliberately omit anything. I also didn't include it
because I can't imagine anyone here knows details about any brand of
alarm panel, who woudln't also know that they're mostly made the same.
 
It's a DSC Power 832. Does that actually help? There are things
about it on the web, and I dl'd some manuals before I found my paper
manuals, but I don't they give an answer.
 
>chip. Could be there is a capacitor on the PCB used to hold the code.
>That capacitor discharged long ago so any value stored in volatile
>memory is gone.
 
But then how did resetting the panel get it back? Of course I could
ask that question about any answer, I guess.
 
> Could be a battery is used instead of a capacitor.
 
I don't think there's a battery. No mention in any manual and I didn't
see one. Certainly no coin battery.
 
micky <NONONOmisc07@bigfoot.com>: Feb 24 02:29AM -0500

I got my new sim, for my trip, today, and the vendor was nice enough to
including a warning that if one has not bought a data plan (and I was
waiting until I got there) he should disable the cellular data or it
will, when prompted to, connect to the internet as pay as you go.
 
Is it enough to disable background data, or will foreground data start
downloading without my realizing it is data? Like if I look at a map
and it decides to update the map? Of if I go to look at an already
dl'd email, and it decides to get new email? I suppose even email
would incur some minimum but substantial charge.
 
I have version 5 and it appears Android has made it very diffeicult to
fullly turn off celluilar data. Only background data is fairly easy.
 
 
 
 
On the web< I looked into all thist. I have Android v.5, and somone
writes in August of 2015:
"There is NO convenient mobile data toggle. It does not exist. That's
the point. A mobile data toggle existed prior to 4.1, as one of the
setting icons, then they eliminated that toggle in 4.+, but 3rd party
apps were developed as a work-around. Now, with 5.+ that wasn't good
enough, so they blocked 3rd party apps so you can no longer disable
mobile data without going through five menu steps to reach it. That
means, when you are not in range of your secure WiFi you either run up
your data bill or simply have a phone with basic messaging. Make your
choice. That's it.
 
....We used to be able to use a 3rd party apps to toggle mobile data to
stay within our data plans and now that is no longer feasible. It's
really nasty and looks intentional as a way to hurt people on lower data
plans by dinging them for overages or forcing them to purchase higher
data plans because there isn't even an icon that shows if you are on
mobile data or not. Hard to believe it's an oversight as you can clearly
see the progression of changes from 3.+ to 5.+"
 
So I looked for mobile data toggle in the play store and
there were 8 apps listed, but two of them did something else, and 6 of
the rest had something wrong with them. Either they said they wouldn't
work with v5, or users said that, or you had to root the phone to use
it, or there's an update for 3 versions ending with 4.1.1
 
 
So is stopping background cellular data enough, or do you have a better
idea?
micky <NONONOmisc07@bigfoot.com>: Feb 25 02:31AM -0500

In sci.electronics.repair, on Sat, 25 Feb 2017 10:20:28 +1100, Clifford
 
>I think so, but it probably depends on the phone.
 
>The advertising for the phone will often say "2nd SIM, standby only",
>which is the give-away that it's only 2G or worse.
 
Darn. It's not mentioned in "advertising" but gsmarena I've looked at
many times and it didn't seem important until just now:
 
Dual SIM (Mini-SIM/ Micro-SIM, dual stand-by)
 
But that's still not conclusive I think. Maybe it's only stand-by when
it's dual, and if I disable one sim, maybe that's not dual anymore.
 
But I won't be able to find out, because I don't even one of the right
bands for G3 on my trip. Maybe I can tell while I'm still in the
US....... It doesn't show G3 but I don't know if it ever does.
 
If I learn anything I'll try to post it here.
 
 
>to the 3/4G network. I think that a true dual SIM phone needs
>to duplicate parts of the networking hardware so it acts like
>two phones; but I am not an expert in such things.
 
Fair enough. I had no plans to buy another phone, but if I dislike G2
and I plan another trip, maybe I will.
 
>> part.
 
>Well, I've just bought a new dual-SIM phone, but not because it
>was dual-SIM.
 
They're more common each year.
micky <NONONOmisc07@bigfoot.com>: Feb 24 01:05AM -0500

In sci.electronics.repair, on Wed, 22 Feb 2017 07:14:05 +1100, Clifford
>> But they BOTH worked on the DASH JR. CLues?
 
>Most "Dual SIM" phones are like that. The 2nd SIM only works on 2G,
>only one SIM can connect to a modern network.
 
More things I should have known in advance**.
 
So if one SIM is removed, will the other do 3G, regardless of which SIM
is left in?
 
Or does it have to be in slot #1? I ask because I too have a Blu phone
(Studio X Plus) with 2 sim slots and so I though tI was being clever to
get micro the second time so that both could be in the phone at one
time. So if "slot 1" is important, Ican't move the SIM anyhow.
 
(I just got the second SIM in the mail today, but I can't use it until
mhy trip starts in 2 weeks.)
 
**Actually today is far better to learn this than after my trip. It's
not in advance of buying the phone but it's in advance of using this
part.
Steve & Lynn <cheryl@must.die>: Feb 23 04:54PM

On 11/18/2016 02:36 AM, Michael A. Terrell wrote:
 
 
> You posted a link with your account ID. That's not very smart, and
> it isn't accessible by anyone else.
 
WHAT ELSE WOULD YOU EXPECT FROM A FAGGOT DEMOCRAT LIKE PETER WRECK
Steve & Lynn <cheryl@must.die>: Feb 23 05:02PM


>> You posted a link with your account ID. That's not very smart, and
>> it isn't accessible by anyone else.
 
> That is the point of DropBox - it allows one to share large and small files without risking a direct connection. My "account ID" is the sharing link. I have used it for years without incident. Nor is there anything in it that is at all actionable or confidential
 
I WOULDN'T WANT TO LOOK AT YOUR DROPBOX ANYWAY. I'M GUESSING YOU HAVE A
VIDEO RIP OF SITRE MAGANA RAPING THAT DOG AND YOU PROBABLY HAVE JPEGS OF
SITRE MAGANA BLOWING THAT 72 YEAR OLD MAN.
Steve & Lynn <cheryl@must.die>: Feb 23 04:49PM

> The Troll is back!
 
AND NOW IT SEEMS THE FAG IS BACK
 
> Please don't feed the troll!
 
AND DON'T FEED THE FAG WHO IS GAYER THAN SITRE MAGANA WHO IS THE OTHER
FAG THAT SUCKED OFF A 72 YEAR OLD MAN AND RAPED A DOG ON VIDEO.
Steve & Lynn <cheryl@must.die>: Feb 23 04:46PM


> "John Harmon", AKA Horation Alger, AKA Raymond Spruance et.al. does not exist except in the diseased and fevered mind of an established but not very clever internet troll.
 
> Peter Wieck
> Melrose Park, PA
 
ANOTHER GAY POST BY PETER WRECK. I MEAN THERE'S A TAPE OUT THERE OF
SITRE MAGANA RAPING A DOG BUT EVEN THAT ISN'T AS GAY AS THIS POST. AND
WHEN YOU POST SOMETHING AND IT IS GAYER THAN A FAG WHO SERVICED A 72
YEAR OLD MAN AND RAPED A DOG ON FILM, THEN YOU KNOW IT'S PROBABLY THE
GAYEST THING ON SCI.ELECTRONICS.REPAIR.
MJC <gravity@mjcoon.plus.com>: Feb 23 07:45PM

I don't remember seeing a question here about ATX PSUs and motherboards.
So if there is a better forum to ask my question no doubt someone will
tell me where...
 
My previous computer became progressively more reluctant to boot up and
eventually I gave up and bought a new ATX PSU in case that was the
problem. That was not a cure so I removed the motherboard as well and
bought a new one. That combination has been working ever since, with
enough problems to be interesting, of course...
 
But I would like to know if anything can be done with the old PSU and
motherboard combination. If I power up the PSU alone by shorting the
green PS_ON connection to ground the fan turns and voltages appear
briefly, but then it goes dead again.
If I connect the PSU to motherboard and short the front panel "on"
contact the same thing happens. The CPU fan turns as well as the PSU
one, but only momentarily.
 
I took the cover off the PSU but the inside shows nothing untoward.
 
Is there anything that I can do for some more diagnosis? The
motherboards is a GA-8ISXT-FS and the PSU FSP300-60ATV with a 20-pin
main power connector.
micky <NONONOmisc07@bigfoot.com>: Feb 24 03:56AM -0500

In sci.electronics.repair, on Thu, 23 Feb 2017 19:41:35 -0000, MJC
>to do
 
>Isn't it just to switch off the screen and touch sensitivity when
>adjacent to your head so your ear doesn't swipe at random?
 
Yeah, that's it. I guess I thought the screen would go off in my front
pants pocket too, light weight pants, but it didn't.
 
I hadn't relied on that, just forgot, and I won't rely on it in the
future. I guess my pants pocket won't swipe anything ilke my ear
could.
 
 
mike <ham789@netzero.net>: Feb 23 11:24AM -0800


>> It's got a proximity sensor but I don't remember what it's supposed to
>> do.
 
> The heat is from the LEDs, not the batteries, and no, the batteries will
 
not last indefinitely. I would guess (SWAG) that each LED will run about
50 ma.
 
So you are pulling 450 ma, or thereabout per hour. If your AAA batteries
are
 
middle-of-the-road 1,000 MAH, you have a base of 3000 MAH, so, about 6-7
hours
 
+/- or so. Under normal use, that is 'days'.
 
> Peter Wieck
> Melrose Park, PA
 
Might want to check that math.
MJC <gravity@mjcoon.plus.com>: Feb 23 07:41PM

In article <3i3uacp6tcf7ivgd290g2lopocr8mug53e@4ax.com>,
jeffl@cruzio.com says...
 
> On Wed, 22 Feb 2017 20:47:57 -0500, micky <NONONOmisc07@bigfoot.com>
> wrote:
> >It's got a proximity sensor but I don't remember what it's supposed
to do
 
Isn't it just to switch off the screen and touch sensitivity when
adjacent to your head so your ear doesn't swipe at random?
 
Mike.
Steve & Lynn <cheryl@must.die>: Feb 23 12:21PM

> Little Timmee got hold of mommy's computer again.
 
> If, of course, it even has a mommy.
 
THAT IS SO FUCKING GAY. THAT WAS SO GAY THAT IT EVEN MAKES SITRE MAGANA
LOOKS STRAIGHT. IF YOU POST SOMETHING AND IT WAS SO GAY THAT IT MAKES
SITRE MAGANA A MAN WHO SERVICED A 72 YEAR OLD MAN AT A GAY ORGAY LOOK
STRAIGHT, THEN YOU KNOW IT MUST BE LIKE THE GAYEST THING IN THE WORLD.
Steve & Lynn <cheryl@must.die>: Feb 23 01:25PM

AND I WENT TO GO SERVICE MYSELF TODAY AND IT APPEARS TO NOT BE DOING
IT'S INTENDED JOB. SHOULD I CLEAN THE JIZZ OFF THE MOTOR OR IS IT A MORE
SERIOUS PROBLEM? WOULD IT BE MORE ECONOMICAL TO BUY A NEW VIBRATING HEAD?
 
SERIOUS REPLIES ONLY.
Steve Kraus <screen@SPAMBLOCKfilmteknik.com>: Feb 23 12:59PM -0600

Four of five timers were trending the same way suggesting power line
frequency.
 
From 2/20 to 2/21 to 2/22:
 
Timer B1 got 47 seconds later then 38 seconds earlier.
 
Timer B2 got 55 seconds later then 58 seconds earlier.
 
Timer C1 got 41 seconds later then 32 seconds earlier.
 
Timer C2 got 82 seconds later then 39 seconds earlier.
 
Timer D1 got 10 seconds earlier then 14 seconds later.
 
The B's are nearly identical to the one whose motor I showed. The C's I've
never had open. The D's I've looked at but have no clue if it's a sync
motor or not. If not, it's kind of funny as that one seems to hew most
closely to the expected turn-on time.
 
Getting a vintage electric wall clock off eBay. Will set it accurately to
an NTP server and then watch it for subsequent variations. Inexpensive way
to look at this and then ultimately a useful device.
"Dave M" <dgminala@mediacombb.net>: Feb 25 05:48PM -0600

Have you tried to contact Hammond for service information? If not, send
them an email with all of the nameplate information and see if they can
help. http://hammondorganco.com/contact-us/service-department/?
Many manufacturers will provide service info free on models that have been
out of production for many years.
 
Cheers,
Dave M
 
 
 
 
"Benderthe.evilrobot" <Benderthe.evilrobot@virginmedia.com>: Feb 27 08:36PM

"Chuck" <chuck@mydeja.net> wrote in message
news:lhm8bcdtqcafq50bkb457c8tj7nrgje52d@4ax.com...
 
> If the problem isn't HV arcing, check or replace parts from pin3 of
> the flyback including the 2 AFC diodes D401 and 402. The diodes on
> this line I'd just replace.
 
A dry joint is also possible, or a noisy part burned resistor dropping
feedback from a flyback winding to the phase discriminator.
 
Arcing usually isn't too hard to see - corona discharge can be, a faint
purple haze around any sharp pointy bit at EHT potential. Sometimes you have
to view the chassis with the light turned off to see it.
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Digest for sci.electronics.repair@googlegroups.com - 25 updates in 18 topics

Jonas Schneider <Jonas123Schneider@arcor.de>: Feb 26 12:32AM

Today I tried to hook up a Rocket M2 as a super powerful (miles) Wi-Fi
extension for my home router, when the POE light went out whenever I
plugged in the power cable. Huh?
 
Turns out it's a crossover cable, mixed up with the bunch of my other spare
Ethernet cables.
 
Do we even need crossover cables anymore?
Or did they go the way of 8-track players?
FrozenNorth <frozennorth.ask@gmail.com>: Feb 25 07:45PM -0500

On 2017-02-25 7:32 PM, Jonas Schneider wrote:
> Ethernet cables.
 
> Do we even need crossover cables anymore?
> Or did they go the way of 8-track players?
 
Most devices do not need cross over cables anymore, but there may still
be the odd one floating around out there.
 
--
Froz....
Joe Chisolm <jchisolm6@earthlink.net>: Feb 24 09:54AM -0600

On Tue, 21 Feb 2017 10:03:40 -0600, Joe Chisolm wrote:
 
> to check availability, price and shipping cost. It also depends on
> where you live. I'm 4 hours driving distance from Mouser so normal
> UPS ground is "next day" for me.
 
I got a email yesterday that Newark is doing $5 shipping on orders < $49 and
free shipping on orders $49 and over. Cavaet is parts must be in a USA
warehouse and shipping to a USA address.
 
 
--
Chisolm
Republic of Texas
Jon Elson <jmelson@wustl.edu>: Feb 21 02:15PM -0600


> What is the best place for a hobbiest to buy small amounts of electronic
> parts?
 
I buy a lot of stuff from Digi-Key. They do have a minimum order, but it is
not that bad. These days, if you buy a few chips as well as passives, you
are pretty likely to go above their minimum (I think it is still $25).
Their single-piece prices are not really steep.
 
Mouser is also pretty good.
 
Jon
Spehro Pefhany <speffSNIP@interlogDOTyou.knowwhat>: Feb 23 11:24PM -0500

On Thu, 23 Feb 2017 13:49:23 -0500, the renowned rickman
>Vietnam and a cyclist was hit. The two drivers started haggling and
>bystanders joined in to mediate. In the end it was decided that the
>cyclist should get $50. They said my friend should pay.
 
Yes, typical Asian logic and I'm all too familiar with it- if the
foreign devil wasn't there the taxi wouldn't have been carrying him,
and thus the cyclist wouldn't have been hit.
 
You can see a smidgeon of that in some of the anti-immigrant rhetoric
on this side of the pond.
 
--sp
 
 
--
Best regards,
Spehro Pefhany
Steve Kraus <screen@SPAMBLOCKfilmteknik.com>: Feb 23 09:55PM -0600

I just had an idea. I have a UPS sitting around out of service as the
batteries went dead and even with good batteries I don't know how long it
would run even at very low load. I don't know how precise it is though
when I looked at it on a scope it was a nice sine wave and looked stable in
frequency compared to the mains. I could rig a 24VDC supply and use the
output of the UPS to run my group of timers that I am testing. If the UPS
has an accurate output then the timers should be accurate as well. If the
UPS is fast or slow then at least the timers will get ahead or behind the
same amount each day, not varying like I have observed. Hopefully it would
be stable at whatever frequency it is and not go up and down.
 
 
Jeroni Paul wrote:
oldschool@tubes.com: Feb 25 08:25PM -0600

I ordered a small amplifier board on ebay. It's just a PCB with
components, making a ready to go low powered audio amplifier, complete
with a volume control.
 
It has three screw terminal blocks to attach the Power, Input and
Output. It also has a 1/8" jack.
 
But here is the problem. Those screw blocks are labelled in Chinese.
Using the actual chinese alphabet. If it was another language, I could
convert the words online, but I cant enter chinese characters.
 
Fortunately, the power one says 12v with a + on one side, so I know that
is the 12v source. But I hav no clue which of the other two are input or
output, nor what that 1/8" plug is for.
 
I bought this from a US seller. You would think he would include a piece
of paper showing what is what. The entire amp is mostly just one IC
chip. Both the input and output go right to this chip, and there are
parts in the way of the chip to try to read the chip numbers. (which
likely would not match anything anyhow). [not to mention I cant see well
enough to read chips anymore].
 
What is most weird, there is a LED on the board which says "LED" and the
caps have numbers next to them (in english).
 
I plan to contact the seller to ask for an email containing the
schematic or a photo showing what is what.....
 
This is the first time I have ever run across a PCB labeled in
chinese...
Steve & Lynn <cheryl@must.die>: Feb 23 04:52PM


> I am not a member of any organized political party. I am a Democrat.
 
O.K. NOW THAT EXPLAINS WHY YOU'RE SO GAY
Ralph Mowery <rmowery28146@earthlink.net>: Feb 23 04:41PM -0500

In article <MPG.33194c2971864c29c@news.plus.net>,
gravity@mjcoon.plus.com says...
 
> Is there anything that I can do for some more diagnosis? The
> motherboards is a GA-8ISXT-FS and the PSU FSP300-60ATV with a 20-pin
> main power connector.
 
AT one time many mother boards were failing because the capacitors on
them were defective. Look at some of the big ones tops, especially near
th eprocessor and those coils of wire. If they are sort of dome shaped
instead of flat, that would be the place to start.
 
Sometimes you could heat the board and it would start and then run for a
long time. Cut it off and you had to heat it again to get it to start.
 
I sent a couple of boards back for replacement due to this problem years
ago.
sam@repairfaq.org (Samuel M. Goldwasser): Feb 23 03:48PM -0500


> When this one craps out/gets too weak I'll do a post mortem, but I
> suspect it uses resistance wire which changes resistance over time.
> If the problem is that, then there's no fixing it.
 
Join the club. :( :) I've had 4 or 5 (yeah I'm a sucker for Sunbeam
blankets) but don't want to be too critical of Sunbeam - they
have replaced several under warranty and replaced one totally.
 
Thee typical symptoms are that they do tend to get weaker over time, but
some die totally. The weakening may be related to the PTC (Positive
Temperature Coefificnt) of resistance of the wire used as the heating
element. It's self limiting so claimed to be safer since even
scrunching up the blanket should not result in an excessive temperature
rise. However, the change in resistance may not be totally reversible.
I doubt using preheat makes a big difference.
Since the power to the heater is pulse width modulated (around an 80
second cycle - yes, that long!), running at lower heat doesn't
necessarily help either.
 
When they totally die, I assume it's a bad connection issue, possibly
at the "module" - the wart attached to the connector, which has a
couple of discrete components inside and nothing else.
 
And I do now record the current used when new. ;-)
 
Google "Sunbeam blanket problems" or something like. There's a lot
out there.
 
--
sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html
 
Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
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micky <NONONOmisc07@bigfoot.com>: Feb 24 07:15PM -0500

In sci.electronics.repair, on Fri, 24 Feb 2017 16:46:20 -0500, Pat
>>who is normally a stickler for things, agreed that I didnt' have to have
>>a battery to run the alarm, since outages are so rare here.
 
>That seems like an odd thing for your friend to say. Alarm systems
 
Thanks for all the advice. It will be valuabe for many people.
 
He knows the kind of crimes that happen here, and he knows them by
neighborhood too (a few years ago he had 800 or maybe it was 1200
customers) , and where I live they don't use fancy tricks like cutting
the power or phone lines. Did I mention I don't live near the
Vanderbilts, or even any doctors or lawyers. (there also aren't many
burglaries because a lot of burglars know there is more money in other
n'hoods** )
 
Where I live they break in. If an alarm goes off, they grab what they
can quickly and they leave quickly.
 
We did discuss routing the phone line, whether the alarm needed to
interrupt the phone line to the phones (because that would be difficult
to arrange here. The phone line no longer goes to the basement. I just
use a cordless phone in the basement, where the alarm is, so the alarm
telephone line and the telephone telephone-line are wired in parallel.).
He pointed out three reasons why it should.
 
If the alarm is between the phones and the phone company, were I on
the phone when the alarm went off, the call would be interrupted, and
that would indicate (though not 100%) that the alarm had gone off. But
I would also hear the siren , whether I'm on the phone or not. He knows
that but he was being complete. (Plus I don't set the alarm when I'm
home. Maybe if I get old and feeble I will.)
 
If he wants to do remote maintenance to the alarm, it works better,
but he pointed out, all I would have to do is turn off my phone
answering machine and not answer the phone.
 
If the alarm does not disconnect the phones, when the burglar comes in
he can take a phone off the hook and stop the alarm from dialing out.
(Is that true. i thought since touch tone, one phone could dial out
even if another phone was off the hook. (I think I tested this once.)
I thought the burglar would have to dial a number or two before the
alarm finished, or started, dialing. That's not so hard because the
phone doesn't dial absolutely immediately. It gives the owner a 10 or
20 seconds to put in the code for example. Maybe he meant all that but
he simplified it for me.)
 
>your house. Same with the phone lines used to dial out for help. It
>is easy to cut land lines. That's why newer alarm panels often use
>cellular.
 
He sells those too.
 
> Not perfect, but it takes more knowledge and equipment to
>jam a cellular call than to cut landline phone wires.
 
** Not many burglaries. 9 years ago I went away for 8 weeks, couldn't
get the alarm working in time, but the house was unchanged when I got
back. And I've seen houses sit vacant for months without any damage at
all. OTOH, kids broke into one vacant house and used it as a clubhouse
until the police scared them out. And 34 years ago, the first summer,
someone kicked open my front door though he didn't steal anything***,
and another time two lawnmowers were stolen (both were very broken), and
another a crummy bicycle without a seat or post was stolen. but the last
two incidents didn't require going into the house.
 
***My burglar alarm was sitting on the bed or the floor, in pieces. I
hadn't taken taken the parts out of the boxes yet. But I stayed home
from work the next day and installed it.
Clifford Heath <no.spam@please.net>: Feb 25 10:20AM +1100

On 24/02/17 17:05, micky wrote:
 
> More things I should have known in advance**.
 
> So if one SIM is removed, will the other do 3G, regardless of which SIM
> is left in?
 
I think so, but it probably depends on the phone.
 
The advertising for the phone will often say "2nd SIM, standby only",
which is the give-away that it's only 2G or worse.
 
> Or does it have to be in slot #1?
 
Again, it probably depends on the phone. Only one can log in
to the 3/4G network. I think that a true dual SIM phone needs
to duplicate parts of the networking hardware so it acts like
two phones; but I am not an expert in such things.
 
> (I just got the second SIM in the mail today, but I can't use it until
> mhy trip starts in 2 weeks.)
 
I wanted a dual SIM phone so I can get SMS (and possible family
emergency calls) while using local data. In any place where 2G
has been shut down, that doesn't work, so I might as well just
have a single SIM phone, and switch over each evening to get
delayed SMS.
 
> **Actually today is far better to learn this than after my trip. It's
> not in advance of buying the phone but it's in advance of using this
> part.
 
Well, I've just bought a new dual-SIM phone, but not because it
was dual-SIM.
oldschool@tubes.com: Feb 25 03:52AM -0600

>at least several thousand Watts. I borrowed a set of ear muffs and sat back
>for a show!
 
>Jon
 
I was at several Grateful Dead concerts in the late 60's and afterwards.
I never saw any such thing. Are you sure you were not "tripping"? That
may have just been a common 6L6 tube in a guitar amp, and your
hallucinations made it look really BIG.... :)
 
Who ever heard of wearing earmuffs at a Grateful Dead concert.....
 
And since you mentioned it. What the hell is wrong with them British?
Valves are plumbing parts. Tubes are electronic parts!!!
 
Seriously, I have heard of using AM transmitter tubes for audio amps. I
dont know what those tubes are numbered, or how much power they output,
but I know that many AM radio stations have power output in the
thousands of watts range. But to use that kind of tube would require
custom output transformers that would likely mimic the pole transformers
used to feed our homes....
 
And just for historic value, the original 1969 Woodstock concert ran
Somewhere between 3500 watts to 12,000 watts, using Mcintosh mi350
monoblock tube amps for their PA system. The article below seems to
conflict whether it was 3,500W or 12,000W.
Either way, that PA system had to cover a very large area, and
apparently it did the job.
 
http://www.mylespaul.com/forums/showthread.php?t=100811
 
These Mcintosh MC3500 power amps have EIGHT power output tubes
6LQ6/6JE6B. These amps had an output of 350W. (mono).
Jon Elson <jmelson@wustl.edu>: Feb 24 04:11PM -0600

> channel...... (And an output transformer about 3 foot big, weighing
> close to the weight of a Harley motor cycle, and costing 10X the price
> for a brand new Harley).....
No, certainly not! You use the modulator from an old AM broadcast
transmitter. I was at a Grateful Dead concert in 1969 and they wheeled out
this THING on the stage with big glass globes, and when they lit up I
realized they were TUBES (valves to the British)! Not sure of the type, but
at least several thousand Watts. I borrowed a set of ear muffs and sat back
for a show!
 
Jon
Ralph Mowery <rmowery28146@earthlink.net>: Feb 20 05:54PM -0500

In article <21omac9vnp8nbi8g7gd8utr45blru7ej4n@4ax.com>,
etpm@whidbey.com says...
> get a Tek 465B. I found one for about a $100.00. It still works great
> and has always been trouble free.
> Eric
 
 
I looked on ebay and did not see anyting in that price range that I
would buy. There were some , but sold as is and not guranteed to work.
They probably will, but I would not take a chance on one if I did not
think I could repair it. Most did not have any probes either. Some
comming out of China are ok and you can get a pair for around $ 20.
 
I agree with the 465B scope, Probably the best analog scope for the
money. I bought one off ebay a few years ago, but it was over $ 200
without the probes. For that kind of money I would go to about $ 300
and get one of the China digital scopes.
sam@repairfaq.org (Samuel M. Goldwasser): Feb 18 03:38PM -0500

> me at "FAKE NEWS" on You Tube (I do not open e-mails for fear of being
> hacked ) Thank you , Don Young ( looking forward to a reply and some
> help )
 
I hope this isn't too controversial. :)
 
I would recommend you get a guaranteed working Tek analog scope on
eBay, probably $100, $150 at most. The newer the better, but if it
is working when you get it, it will probably serve you long enough
to satisfy your needs.
 
DSOs are great once you have some familiarity with what to expect, but
can be very deceiving if you don't.
 
--
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Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html
 
Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
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Jeff Liebermann <jeffl@cruzio.com>: Feb 23 08:44AM -0800

On Wed, 22 Feb 2017 20:47:57 -0500, micky <NONONOmisc07@bigfoot.com>
wrote:
 
>I have one of thoe little 2.5" LED flashlights, that have 9 small LEDs
>and use 3 AAA batteries. It's like the ones that Harbor Freight
>sometimes gives away free, same size, but nicer.
 
Did you notice that almost all such flashlights are made from
aluminum, not plastic, which would be cheaper? That's because
aluminum makes a good heat sink to get the heat away from the LED's.
LED's loose output and efficiency when hot, so it pays to keep them
cool. The COB style of LED mounting is quite common in larger
flashlights, which offer a heat conductive path from the LED to the
aluminum heatsink case.
 
>warm.
 
>It's still really bright, but if it's noticeably warm, how long can the
>baterries really last? Certainly not two days. ?
 
No, it won't run forever. AAA alkaline batteries are good for
1000ma-hr each. At something less than 4.5V for 3 batteries, that's
4.5 watt-hrs. Commodity LED's generate about 50 lumens/watt, so if
your Harbor Freight flashlight managed to belch 15 lumens, it will
consume 0.3 watts. Runtime is therefore an optimistic:
4.5 watt-hrs / 0.3 watts = 15 hrs.
It's probably less because I didn't bother throwing in losses in the
current source, decrease in battery voltage as it runs down, and
heating effects. But, it should give you a ballpark guess as to how
long it will run. My guess(tm) is it will run about 8 hrs with a new
set of batteries.
 
>I once, recently, forgot the screen was lit on my 5.5" smart phone and
>only noticed because it felt warm in my pocket.
 
If your smartphone as a battery usage graph, like all Android phones,
you'll find that it also has a list of which applications are sucking
the most power. The backlighting for the OLED screen is invariably
the highest. If you don't talk on your phone, and don't run any apps,
the battery life of your phone will be totally dependent on the
brightness setting and efficiency of the OLED display, which is about
the same 50 lumens/watt as your white LED. (Yes, I know there are
press releases for >100 lumens/watt, but those are under laboratory
conditions).
 
>It's got a proximity sensor but I don't remember what it's supposed to
>do.
 
Never heard of it. Maker and model number?
 
--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Michael Black <et472@ncf.ca>: Feb 24 06:47PM -0500

Steve & Lynn <cheryl@must.die>: Feb 24 11:40AM

> On Monday, February 13, 2017 at 3:05:42 PM UTC-5, jurb...@gmail.com wrote:
 
> Peter Wieck
> Melrose Park, PA
 
Laughable Ill-Informed Blaming Entitled Race-Bating Anti-Capitalist
Loudmouth
frank <frank@invalid.net>: Feb 25 06:29PM

Hi all,
I'm trying to keep an old TV alive, it's an old 14CT2306/20S from Philips
and it's the only think that fits into a furniture space in my parent's
house, so that will not be replaced. I'm keeping it alive for 30+ years now.
The LOPT developed some leaks in the past years but they where on the external
side so I was always able to scratch the hole zones and put some epoxy that
cured the leak. Lately it developed a nasty leak to the internal core, so
it's time to find a replacement for it.
I ordered an HR-6098 LOPT on ebay based on diemen HR equivalence and when
it arrived, I noticed that it lacks pin 1.
On the diemen site, the HR-6098 indeed has pin 1, schematics and actual
chassis both agree that pin 1 is needed as horizontal signal going into
an LM339 comparator, so I think I can't put this transformer in place
of the original one.
The ebay seller just said that since it's stamped with the correct name,
it must be it and I'm just not able to install it correctly :)
Is there any chance that the seller is right or my only option is asking
for a refund via PayPal?
What could be going on here? I wouldn't believe it's viable to make
fake LOPT anyway. Maybe a mis-labeled unit that was so similar to the
rigth one?
 
Thanks
Frank
micky <NONONOmisc07@bigfoot.com>: Feb 22 08:41PM -0500

Years ago, I was told not to play my stereo with no speakers, for fear
of somethun' or other. Of course that was 1968, a good year for audio.
 
Is this still an issue with current electronics, like audio amplifiers
and burglar alarm amplifiers?
 
Now I have a home burglar alarm that might be in the alarm status. I
can't tell because I disconnected part of it, until I can find out how
to disarm it.
 
I have two horns and a siren driving amplifier board, so that they're
louder than the mere alarm control panel can provide. I have a glass
fuse in the line to each speaker.
 
So if I take the fuse out but the siren driver is still functioning, do
I risk burning it out? Even if it's like this for say, 20 hours?
 
Or can it go like this with no harm to itself?
 
What if I disconnect the siren driver from the control panel? They're
separate boards. Do I risk burning out the output of the alarm control
panel, if say it is run. again, 20 hours?
 
Or can it go like this with no harm to itself?
 
 
Those are the questions. The rest here is just a narrative, soon to be a
major motion picture.
 
20 hours is how long I need to look into it, sleep, and then contact my
friend who runs an alarm business. But I'd really like to do as much as
possible on my own. He's constantly doing favors for me and a couple
days ago he wanted to send over his technician to finish the
installation for me. I can offer to pay; i can insist on paying, but I
know he won't let me, and, trust my judgment, he probably wants the
kavod of helping me more than he wants the money. Plus my own ego is
involved in wanting to do it myself...., so I really shouldn't be asking
you any questions either. But it's different. None of you are coming to
my house to do it.
 
The reason it's running is that I tried the original default master
code, several times, and it didn't work. It wouldn't arm the system,
but I wanted to hear if the siren worked (this system has never been
tested before) and soon I got the bright idea to arm it another way.
there is an Away button which when pushed for 2 seconds arms it without
the code. Well the siren works, as well as it did when I had my
previous system installed (designed and installed by me, but it burned
out after 15 years. Lightning?) but I didn't look far enough ahead to
realize still didn't have a code that worked and I have no way to turn
it off.
 
Well, I unplugged it, and the battery hasn't been charged in 9 years, so
that turned it off, but I need to work on it and the moment I plugged it
in again, it armed itself.
Steve & Lynn <cheryl@must.die>: Feb 22 06:27PM

> This is slightly off topic....
 
 
> From what I am seeing, those transformers are all under rated. A friends
> house has 200A service and his transformer is only 8KVA.
 
WHAT SIZE TRANSFORMER DO YOU SUPPOSE SITRE MAGANA NEEDS IN ORDER TO PLAY
WITH HIS OWN SHIT?
 
HOW MANY VOLT-AMPERES DOES ONE NEED TO FUCK A 72 YEAR OLD MAN AT A GAY ORGY?
 
HOW MANY AMP SERVICE DO YOU NEED TO CUT A HAMSTER TO PIECES WITH A PAIR
OF SCISSORS?
ohger1s@gmail.com: Feb 27 04:51PM -0800


> * If anyone knows of a COMPLETE listing that can be downloaded, such as
> a PDF file, please post the URL. (or even a text file). I am not finding
> anything that's complete......
 
The IB3 is easy. The IB3, 3A3, 2AV2 etc. are all HV rectifiers, and the filaments were designed to run off parasitic windings of the HV transformers. The less turns the better I guess. The 1B3 was for B&W TVs, the 3A3 for color TVs which, not coincidentally, had about twice the HV as the B&W versions, so a turn or so around the core would give the correct voltage.
 
Tubes like the 800 series or the early 4 pin radio tubes were never part of the standard numbering scheme, and as for the others, if you consider the many thousands of tubes from dozens of manufacturers that were pigeon-holed into the handful of basic types, you'd need unique letters just to identify them.
Phil Allison <pallison49@gmail.com>: Feb 27 07:26PM -0800


> And then there were those old 1B3 tubes in TV sets. Where did the 1 volt
> heater voltage come from? (and why didn't they just stick with 6.3 volts
> like other tubes?)
 
** Like all rectifier tubes, the cathode is the output point and in this case can be up to +26kv above ground.
 
The 6.3V heater chain used by other tubes cannot be used as a 26kV insulation barrier would stop all heat getting to the cathode. So the tube cathode is directly heated by a winding that floats at the HT voltage.
 
http://www.radiomuseum.org/tubes/tube_1b3.html
 
Since the load current is 50mA max, a low powered heater is enough - 1.25V and 200ma do the job.
 
The 1.25V needed is conveniently derived by a single turn around the HOT core, carried out with wire insulted to stand 20kV or more.
 
 
.... Phil
Chuck <chuck@mydeja.net>: Feb 27 10:59AM -0600

On Sun, 26 Feb 2017 14:06:31 -0800, John Robertson <spam@flippers.com>
wrote:
 
 
>Suggestions appreciated!
 
>Thanks,
 
>John :-#)#
 
If the problem isn't HV arcing, check or replace parts from pin3 of
the flyback including the 2 AFC diodes D401 and 402. The diodes on
this line I'd just replace.
 
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