sci.electronics.repair - 25 new messages in 10 topics - digest

sci.electronics.repair
http://groups.google.com/group/sci.electronics.repair?hl=en

sci.electronics.repair@googlegroups.com

Today's topics:

* Hi, WOuld some kind soul help me diagnose my switch mode power supplies? - 4
messages, 4 authors
http://groups.google.com/group/sci.electronics.repair/t/e0182493b4e28ce4?hl=en
* Challenge of Repairing vs Trashing - 2 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/3cd5c17c8ebe1b1c?hl=en
* Lead free solder - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/7ff46ef49e9b7de3?hl=en
* Video cassette - topology question - 5 messages, 4 authors
http://groups.google.com/group/sci.electronics.repair/t/0684ad9ffa290aba?hl=en
* Annoying Clock on Microwave - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/408849711f765a28?hl=en
* Has anyone tried this product for heat-sink compound? - 2 messages, 2
authors
http://groups.google.com/group/sci.electronics.repair/t/6163429af05daf16?hl=en
* Found: E book stash. - 6 messages, 3 authors
http://groups.google.com/group/sci.electronics.repair/t/e957cecc59313da7?hl=en
* ADULT SEX PHOTOS - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/8502d92d715cb4df?hl=en
* Really "need to" replace older CATV cables? Would my cableprovider really
filter my line against my will? - 2 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/31e43b6766887486?hl=en
* Mopar model 812 car radio, (early 1950's Chrysler product) - 1 messages, 1
author
http://groups.google.com/group/sci.electronics.repair/t/3135639c17d6af1d?hl=en

==============================================================================
TOPIC: Hi, WOuld some kind soul help me diagnose my switch mode power supplies?

http://groups.google.com/group/sci.electronics.repair/t/e0182493b4e28ce4?hl=en
==============================================================================

== 1 of 4 ==
Date: Mon, Apr 25 2011 12:50 am
From: Kripton

On 2011-04-24 23:03:16 +0200, "Stephen" <i.want.spam@spam.com> said:

> If a capacitor has gone dry, wouldn't there be a clue like bulging tops,
> leaking brown crud, and a horrible smell when they get hot?
>
> Regards,
>
> Stephen

you can make a quick esr analog meter to check all your caps
the small capacitor next to the uc3842 aways fails to an esr meter
even a cheap build from scratch analog one.

my web site contains easy and more complex esr meter to build yourself
regards,

http://kripton2035.free.fr/esr-repository.html

--
---
Kripton

== 2 of 4 ==
Date: Mon, Apr 25 2011 3:35 am
From: JW

On Sun, 24 Apr 2011 16:44:02 +0100 "Stephen" <i.want.spam@spam.com> wrote
in Message id: <I8Odncf6apym2CnQnZ2dnUVZ8vqdnZ2d@brightview.co.uk>:

>capxon
^^^^^^

Shoot on sight. Capxon makes crap. Also Lelon, Luxon, and GSC off the top
of my head.

== 3 of 4 ==
Date: Mon, Apr 25 2011 8:07 am
From: "Stephen"

Wow.... What can I say......

I bought two new new 22µF 50V 105°C capacitors today, total cost 42 pence.
(About 0.5? or 50 cents for the rest of the world)

took the first faulty unit, swapped over the 22µF 50V capxon, tested it and
it worked.

I then took the 2nd faulty unit.... Swapped over the 22µF 50V capxon, tested
it and it worked.

Thank you, Wicaksono, Kripton, Plain Bill and Who Where, you were all on the
nail.....

As a token of gratitude, I think I should give some background to the
story.....

I am in the reception area for 4 TV transmitters in four different
directions and want to get TV channels from all four. Simple aerial group
combiners with grouped Yagi aerials would not work as the frequencies used
at each transmitter overlap at least one of the other 3. One way of solving
this is to used a channelised head end UHF amplifier.

These units have 10 frequency agile filters, with independently adjustable
gain, and can accommodate up to 3 UHF aerials as well as an FM radio aerial
and a Band III aerial.

These units are still available for £400 each ( around ?400 or $400 each.)
via wholesalers.

So I bought 2 off Ebay complete with a programmer. One worked, the other
didn't. After haggling with the seller, I got half the money back and was
allowed to keep the faulty unit, so it cost me £100 all told.

I kept an eye for more on Ebay. Another one came up, I was the only bidder
and bought it for £5 (about ?5 or $5) This was too also faulty with an
identical fault. I didn't raise a dispute given it was beer money, and if
the worst came to the worst, it could be cannabilised for spare parts.

I contacted the Spanish manufacturers of these units enquiring about a PSU
repair kit. "sorry, these units are no longer being made, you need to buy
the new version 2 unit. These are £500 each and the only difference is the
addition of a SD memory card slot allowing you to copy settings from one
unit to another."

So now thanks to the advice given here, I now have 3 working units instead
of 1 working and two faulty.....

So now I could combine up to 9 UHF aerials, 3 FM aerials and 3 Band III
aerials all pointing in different directions, combine the three units
outputs using a passive combiner, and feed that lot into my 17x16
multiswitch.... :-)

I also plan to add CCTV at some point in the future so these units will
allow me to combine digital TV with analogue CCTV too....

Thanks again,

Stephen

"JW" <none@dev.null> wrote in message
news:tfjar6ho20o7mae6c1kru71lu1n5p2qaif@4ax.com...
> On Sun, 24 Apr 2011 16:44:02 +0100 "Stephen" <i.want.spam@spam.com> wrote
> in Message id: <I8Odncf6apym2CnQnZ2dnUVZ8vqdnZ2d@brightview.co.uk>:
>
>>capxon
> ^^^^^^
>
> Shoot on sight. Capxon makes crap. Also Lelon, Luxon, and GSC off the top
> of my head.
>

== 4 of 4 ==
Date: Mon, Apr 25 2011 9:12 am
From: "Arfa Daily"

We need to get some posting consistency here. With half the respondents top
posting, and half bottom posting, it's becoming impossible to follow the
thread. Please all stick to bottom posting, as is the normally accepted
protocol in usenet newsgroups.

Right, Now that's out of the way. The voltages being quoted make no sense
against the drawn schematic that the OP provided. If pin 4 of the ribbon is
connected directly to the output of a 7805, then the voltage at that point
*must* be +5v on the unit that is working. It cannot possibly be at +30.2v -
period. This indicates that what you have picked as your reference ground to
measure against, isn't a valid secondary side ground. Bear in mind that the
primary side ground and secondary side ground on a switchmode power supply,
are very different. The valid ground for your measurements, should be taken
as the centre pin of the 7805. You might think that other places on the
board or within the circuit configuration are the same ground, but without a
manufacturer's schematic, you just can't be sure, so use a point that you
can be sure of or at least 99% sure of. I say only 99%, because
occasionally, you will see the output of a three terminal monolithic
regulator 'jacked' a little by the insertion of a diode or two in the ground
leg, but it's pretty rare on proper commercial equipment.

When you have reached a point where you can read a steady +5v on the
righthand pin of the 7805, then remeasure the other voltages, and let's see
if they make some more sense,

Arfa

==============================================================================
TOPIC: Challenge of Repairing vs Trashing
http://groups.google.com/group/sci.electronics.repair/t/3cd5c17c8ebe1b1c?hl=en
==============================================================================

== 1 of 2 ==
Date: Mon, Apr 25 2011 2:38 am
From: "Arfa Daily"

"nesesu" <neil_sutcliffe@telus.net> wrote in message
news:9d55d6fb-31b4-45de-8cf4-4d53b3c24860@k3g2000prl.googlegroups.com...
> On Apr 24, 9:15 am, "Dave M" <dgminala4...@mediacombb.net> wrote:
>> Robert Macy wrote:
>> > Have one of those small aluminum tube LED flashlights, approx 3 inch
>> > long. During use on a cold night [40F], it suddenly started
>> > flickering, rather than constantly on. After putting in a new battery,
>> > the same.
>>
>> > Now no matter where even warm office, LED flashlight flickers.
>>
>> > Rate 'appears' to be 8-12/sec with a 70-30/80-20 ON cycle.
>>
>> > Any ideas if it's possible to fix?
>>
>> Therese things are so simple, it's almost embarrassing to ask how to fix
>> them. Temperature isn't the cause of the problem.
>> Most likely the on-off switch has pitted contacts. Disassemble the
>> switch
>> and burnish of file the contacts until the pitting is gone.
>> Another possibility is that the switch contacts have lost "springiness"
>> and
>> are barely making contact. Dissasemble the switch and bend them until
>> there
>> is sufficient force to make firm contact.
>> If there is no switch (the head and the tube are screwed together to turn
>> the flashlight on), disassemble the flashlight and clean the dirt or
>> other
>> stuff that's keeping the pieces from making good contact.
>> Last, see if the button of solder in the head that contacts the battery,
>> has
>> taken a depression so that it's not making contact with the battery. If
>> so,
>> put another good blob of solder on it to make vetter contact.
>> --
>> David
>> dgminala at mediacombb dot net
>
> Not so sure about that. I have noticed that my cheap 3 LED flashlight
> puts out a moderate RFI when on. Presumably there is a switcher of
> some sort that ups the 1.4V from a single AA cell to run the 3 LEDs.
> If the OP's one has asimilar switcher, it could have failed in the
> cold [poor Pb free solder joint?] and remained faulty when warmed back
> up again.
>
> Neil S.

That would be my thoughts, too. These flashlights are often not quite as
simple as the other poster seems to believe, and it's common to have an
inverter chip built in which, in conjunction with a small external choke,
produces the required voltage at a constant current, to run the LED(s) until
the battery or single cell has reached way below where it would normally
power anything, let alone one or more white LEDs. There are many examples of
how this all works on the 'net. A couple of years ago, Elektor magazine gave
away a little board with one of these ICs and a choke on it, free on the
front of every copy, for readers to play with. I still have mine connected
to a white LED set in the end of an old ball pen tube to use as a light
'probe' when looking for problems deep in CD or tape mechanisms where the
normal bench light won't reach. It runs from a single NiCd cell and remains
at full brightness until the cell just falls over and dies.

Just an additional thought. The problem could also be the LED itself. I have
seen them go intermittent, and if this one is being pulse driven from an IC,
then it might well be that a faulty LED would flicker as the chip tries to
keep it supplied with a constant pulse current.

Arfa

== 2 of 2 ==
Date: Mon, Apr 25 2011 3:57 am
From: "N_Cook"

Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:sibtp.35070$KZ7.25040@newsfe08.ams2...
>
>
> "nesesu" <neil_sutcliffe@telus.net> wrote in message
> news:9d55d6fb-31b4-45de-8cf4-4d53b3c24860@k3g2000prl.googlegroups.com...
> > On Apr 24, 9:15 am, "Dave M" <dgminala4...@mediacombb.net> wrote:
> >> Robert Macy wrote:
> >> > Have one of those small aluminum tube LED flashlights, approx 3 inch
> >> > long. During use on a cold night [40F], it suddenly started
> >> > flickering, rather than constantly on. After putting in a new
battery,
> >> > the same.
> >>
> >> > Now no matter where even warm office, LED flashlight flickers.
> >>
> >> > Rate 'appears' to be 8-12/sec with a 70-30/80-20 ON cycle.
> >>
> >> > Any ideas if it's possible to fix?
> >>
> >> Therese things are so simple, it's almost embarrassing to ask how to
fix
> >> them. Temperature isn't the cause of the problem.
> >> Most likely the on-off switch has pitted contacts. Disassemble the
> >> switch
> >> and burnish of file the contacts until the pitting is gone.
> >> Another possibility is that the switch contacts have lost "springiness"
> >> and
> >> are barely making contact. Dissasemble the switch and bend them until
> >> there
> >> is sufficient force to make firm contact.
> >> If there is no switch (the head and the tube are screwed together to
turn
> >> the flashlight on), disassemble the flashlight and clean the dirt or
> >> other
> >> stuff that's keeping the pieces from making good contact.
> >> Last, see if the button of solder in the head that contacts the
battery,
> >> has
> >> taken a depression so that it's not making contact with the battery.
If
> >> so,
> >> put another good blob of solder on it to make vetter contact.
> >> --
> >> David
> >> dgminala at mediacombb dot net
> >
> > Not so sure about that. I have noticed that my cheap 3 LED flashlight
> > puts out a moderate RFI when on. Presumably there is a switcher of
> > some sort that ups the 1.4V from a single AA cell to run the 3 LEDs.
> > If the OP's one has asimilar switcher, it could have failed in the
> > cold [poor Pb free solder joint?] and remained faulty when warmed back
> > up again.
> >
> > Neil S.
>
> That would be my thoughts, too. These flashlights are often not quite as
> simple as the other poster seems to believe, and it's common to have an
> inverter chip built in which, in conjunction with a small external choke,
> produces the required voltage at a constant current, to run the LED(s)
until
> the battery or single cell has reached way below where it would normally
> power anything, let alone one or more white LEDs. There are many examples
of
> how this all works on the 'net. A couple of years ago, Elektor magazine
gave
> away a little board with one of these ICs and a choke on it, free on the
> front of every copy, for readers to play with. I still have mine connected
> to a white LED set in the end of an old ball pen tube to use as a light
> 'probe' when looking for problems deep in CD or tape mechanisms where the
> normal bench light won't reach. It runs from a single NiCd cell and
remains
> at full brightness until the cell just falls over and dies.
>
> Just an additional thought. The problem could also be the LED itself. I
have
> seen them go intermittent, and if this one is being pulse driven from an
IC,
> then it might well be that a faulty LED would flicker as the chip tries to
> keep it supplied with a constant pulse current.
>
> Arfa
>

I like the inadvertent buit-in charge meter of multi-LED torch lamps where
they are all in parallel (plus a bit of pcb trace drop). You can tell the
state of battery charge as one or more fail to illuminate, more "failing"
with less charge/voltage .

==============================================================================
TOPIC: Lead free solder
http://groups.google.com/group/sci.electronics.repair/t/7ff46ef49e9b7de3?hl=en
==============================================================================

== 1 of 1 ==
Date: Mon, Apr 25 2011 2:45 am
From: "Arfa Daily"

"Mike Tomlinson" <mike@jasper.org.uk> wrote in message
news:D81zLmAMB6sNFwsX@jasper.org.uk...
> In article <ioufiu$erh$1@dont-email.me>, William Sommerwerck
> <grizzledgeezer@comcast.net> writes
>
>>I hate callbacks. I would use lead-based solder on repairs.
>
> Me too, made sure I'm well stocked up on lead-based solder.
>
> --
> (\__/)
> (='.'=)
> (")_(")
>
>

There is no shortage of lead-based solder, nor is there likely to be in the
near future. There is still plenty of equipment in the market which is
produced by sectors that have an exemption for their product class, and
equipment produced and owned from before June 2006. In both of these cases,
it is acceptable - and indeed desirable - to use lead-based solder for
repairs, modifications and upgrades.

Arfa

==============================================================================
TOPIC: Video cassette - topology question
http://groups.google.com/group/sci.electronics.repair/t/0684ad9ffa290aba?hl=en
==============================================================================

== 1 of 5 ==
Date: Mon, Apr 25 2011 3:50 am
From: "N_Cook"

If a tape gets scrunched up and loops once around the pivot, inside the
spool, jammed between the hank of tape and the "top" spool flange. Taking
the cover of the cassette off and removing one spool. Keeping both spools
horizontal, you unwind the scrunched loop by pulling out. Then would you
expect to have to flip one spool , one turn, to bring tape laying back to
normal? Would that removal of a twist in the tape mean the scrunched tape
has looped over the top of the spool flange before scrunching or stayed
within the plane of the normal tape passage, ie the volume of space of
width of the tape.

== 2 of 5 ==
Date: Mon, Apr 25 2011 4:02 am
From: "William Sommerwerck"

I'm not sure I actually understand your question. However...

Most (if not all) VCR tapes, regardless of format, are "B wind" -- the oxide
faces "out".

Most analog audio reel-to-reel formats are "A wind" -- the oxide faces "in".
Most analog audio cartridge and cassette formats are "B wind".

It doesn't matter "who struck John". You want the tape to go in straight
line from one hub to the other, with oxide facing the "outside" of the
cartridge.

Mr Cook, your writing is often unclear. You sometimes write as if English
were not your native language. You need to learn to write more clearly.

== 3 of 5 ==
Date: Mon, Apr 25 2011 4:34 am
From: "Phil Allison"

"William Sommerwerck"
>
> Mr Cook, your writing is often unclear. You sometimes write as if English
> were not your native language. You need to learn to write more clearly.
>

** Not possible to write better than he thinks.

Need a brain transplant to fix that.

.... Phil

== 4 of 5 ==
Date: Mon, Apr 25 2011 7:41 am
From: spamtrap1888

On Apr 25, 4:02 am, "William Sommerwerck" <grizzledgee...@comcast.net>
wrote:
> I'm not sure I actually understand your question. However...
>
> Most (if not all) VCR tapes, regardless of format, are "B wind" -- the oxide
> faces "out".
>
> Most analog audio reel-to-reel formats are "A wind" -- the oxide faces "in".
> Most analog audio cartridge and cassette formats are "B wind".
>
> It doesn't matter "who struck John". You want the tape to go in straight
> line from one hub to the other, with oxide facing the "outside" of the
> cartridge.
>
> Mr Cook, your writing is often unclear. You sometimes write as if English
> were not your native language. You need to learn to write more clearly.

As I understood him, he asked if videocassette tape was meant to have
a half-(or greater-) twist. Or, by extension, should it lay untwisted
like an audiotape, whether open reel or cassette.

== 5 of 5 ==
Date: Mon, Apr 25 2011 8:16 am
From: "William Sommerwerck"

>> Mr Cook, your writing is often unclear. You sometimes write
>> as if English were not your native language. You need to learn
>> to write more clearly.

> As I understood him, he asked if videocassette tape was meant
> to have a half- (or greater) twist. Or, by extension, should it lay
> untwisted like an audiotape, whether open reel or cassette.

Thanks.

The answer, of course, is untwisted.

==============================================================================
TOPIC: Annoying Clock on Microwave
http://groups.google.com/group/sci.electronics.repair/t/408849711f765a28?hl=en
==============================================================================

== 1 of 1 ==
Date: Mon, Apr 25 2011 4:05 am
From: "William Sommerwerck"

>> I find it impossible to believe that /any/ microwave oven
>> would use a crystal or resonator -- which costs money --
>> when the power frequency is /right there/, and free.

> They would use the same crystal as the microprocessor,
> and run the clock in software.

I was, of course, referring to a separate crystal (he said, retro-conning
the issue).

==============================================================================
TOPIC: Has anyone tried this product for heat-sink compound?
http://groups.google.com/group/sci.electronics.repair/t/6163429af05daf16?hl=en
==============================================================================

== 1 of 2 ==
Date: Mon, Apr 25 2011 5:17 am
From: Bob Villa

On Apr 24, 10:07 pm, "Barry" <n...@nospam.org> wrote:
> "Bob Villa" <pheeh.z...@gmail.com> wrote in message
>
> news:0a0e4aa2-74a4-4c20-bb66-5b2b021bec7f@u15g2000vby.googlegroups.com...
>
> >http://www.permatex.com/products/automotive/automotive_gasketing/gask...
>
> > It would "seem" to have good properties for filling minute gaps;
> > copper for heat transfer; can't dry-out; not a bonding type on
> > silicone.
>
> > Thanks
> > bob_v
>
> This stuff is NOT a silicone grease but rather a room temperature
> vulcanizing silicone rubber. There is no copper in it, and it is a poor
> heat conductor. General Electric used to be the manufacturer, but it
> appears that they have sold out to a Chinese company. If memory serves
> it used to be either RTV-60, RTV-650, or RTV-106. I cannot remember
> which is the two-part and which is the one-part material. MG Chemicals
> is a distributor for Momentive Performance Materials, the _obviously_
> Chinese company that makes it now. They do make two higher thermal
> conductivity silicones known as TSE3331 and TSE3941. The former is a
> grey potting and encapsulating compound while the latter is a white
> adhesive.
>
> As Jeff Liebermann <je...@cruzio.com> pointed out, the smoother the
> surfaces are and the closer they fit, the better the heat transfer will
> be. All the silicone heat transfer grease does is fill the microscopic
> void spaces (dead air space is a good thermal insulator).
>
> Working around chemists, I had easy access to silicone vacuum stopcock
> grease. I have used it in a pinch for thermal grease and it worked well.
> You can find a similar grease in the plumbing department of Lowes and
> Home Depot. It is used to lubricate valve stems, rubber seals, and those
> ungodly expensive ceramic Price-Pfister faucets. It will work far better
> than any Permatex product as a heat transfer grease.
>
> Oh, and one other reason to not use Permatex in this application. This
> silicone is an acetoxy cure which means it releases corrosive acetic acid
> when it cures.
>
> Dr. Barry L. Ornitz WA4VZQ ham_call_letters at live.com

Thank you, Dr.

== 2 of 2 ==
Date: Mon, Apr 25 2011 6:31 am
From: Rich Webb

On Sun, 24 Apr 2011 12:12:58 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:

>On Sun, 24 Apr 2011 10:12:28 -0700 (PDT), Bob Villa
><pheeh.zero@gmail.com> wrote:
>
>>The reason I think it's a possible a good substitute is...it squeezes
>>down to an extremely thin film. If surfaces are nearly perfect...there
>>would be almost nothing between them.
>
>Have you ever measured the thermal transmission characteristics of
>various heat sink mounting methods and the effects of thermal grease?
>I have (in about 1993) using a home made fixture[1]. I have the
>report buried somewhere, but as I vaguely recall, the best thermal
>conductivity was achieved when both the device and the aluminum heat
>sink were polished flat until they looked like mirrors, with no
>thermal grease in between.

Overclockers used to (and may still; I don't play any more) spend a fair
amount of time on this for CPU heatsinks. I gave it a spin once, using a
polished marble building tile for the reference surface, successive
grades of wet-work polishing paper, and a lot of water. Much work for
just a few degrees change in delta-T but it was instructive. Also, it
was pretty cool to see just how well-polished one could get a copper
surface.

--
Rich Webb Norfolk, VA

==============================================================================
TOPIC: Found: E book stash.
http://groups.google.com/group/sci.electronics.repair/t/e957cecc59313da7?hl=en
==============================================================================

== 1 of 6 ==
Date: Mon, Apr 25 2011 8:36 am
From: "Ian Field"

http://www.unhas.ac.id/tahir/ebook/

== 2 of 6 ==
Date: Mon, Apr 25 2011 9:46 am
From: Don McKenzie <5V@2.5A>

On 26-Apr-11 1:36 AM, Ian Field wrote:
> http://www.unhas.ac.id/tahir/ebook/

WOW!
That is some find Ian.
Like a freshly discovered golden Easter egg :-)

Posted 2008. I wonder if it is permanent.

Cheers Don...

======================

--
Don McKenzie

Dontronics Blog: http://www.GodzillaSeaMonkey.com
Dontronics Site Map: http://www.dontronics.com/sitemap
E-Mail Contact Page: http://www.dontronics.com/email
Web Camera Page: http://www.dontronics.com/webcam
No More Damn Spam: http://www.dontronics.com/spam

These products will reduce in price by 5% every month:
http://www.dontronics-shop.com/minus-5-every-month.html
http://www.dontronics-shop.com/ics.html

Bare Proto PCB for PIC or AVR projects?
"I'd buy that for a Dollar!".

== 3 of 6 ==
Date: Mon, Apr 25 2011 10:02 am
From: "Ian Field"

"Don McKenzie" <5V@2.5A> wrote in message
news:91lmr7FkkqU1@mid.individual.net...
> On 26-Apr-11 1:36 AM, Ian Field wrote:
>> http://www.unhas.ac.id/tahir/ebook/
>
> WOW!
> That is some find Ian.
> Like a freshly discovered golden Easter egg :-)
>
> Posted 2008. I wonder if it is permanent.

http://www.oldradios.co.nz/downloads/

== 4 of 6 ==
Date: Mon, Apr 25 2011 10:03 am
From: "Ian Field"

http://www.oldradios.co.nz/downloads/

>
> Cheers Don...
>
> ======================
>
>
> --
> Don McKenzie
>
> Dontronics Blog: http://www.GodzillaSeaMonkey.com
> Dontronics Site Map: http://www.dontronics.com/sitemap
> E-Mail Contact Page: http://www.dontronics.com/email
> Web Camera Page: http://www.dontronics.com/webcam
> No More Damn Spam: http://www.dontronics.com/spam
>
> These products will reduce in price by 5% every month:
> http://www.dontronics-shop.com/minus-5-every-month.html
> http://www.dontronics-shop.com/ics.html
>
> Bare Proto PCB for PIC or AVR projects?
> "I'd buy that for a Dollar!".
>

== 5 of 6 ==
Date: Mon, Apr 25 2011 10:19 am
From: Don McKenzie <5V@2.5A>

On 26-Apr-11 3:03 AM, Ian Field wrote:
> "Don McKenzie"<5V@2.5A> wrote in message
> news:91lmr7FkkqU1@mid.individual.net...
>> On 26-Apr-11 1:36 AM, Ian Field wrote:
>>> http://www.unhas.ac.id/tahir/ebook/
>>
>> WOW!
>> That is some find Ian.
>> Like a freshly discovered golden Easter egg :-)
>>
>> Posted 2008. I wonder if it is permanent.
>
>
>
> http://www.oldradios.co.nz/downloads/

Thanks Ian,

I'll add that to my Electronic Links page.

Cheers Don...

============================

--
Don McKenzie

These products will reduce in price by 5% every month:
http://www.dontronics-shop.com/minus-5-every-month.html
http://www.dontronics-shop.com/ics.html

Bare Proto PCB for PIC or AVR projects?
"I'd buy that for a Dollar!".

== 6 of 6 ==
Date: Mon, Apr 25 2011 10:57 am
From: Jeff Liebermann

On Mon, 25 Apr 2011 16:36:03 +0100, "Ian Field"
<gangprobing.alien@ntlworld.com> wrote:

>http://www.unhas.ac.id/tahir/ebook/

Both of those directories are also available via Bitorrent.
<http://torrentz.eu/any?q=all+electrical+and+electronic+ebooks>
<http://torrentz.eu/search?f=600+electrical+engineering>

--
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

==============================================================================
TOPIC: ADULT SEX PHOTOS
http://groups.google.com/group/sci.electronics.repair/t/8502d92d715cb4df?hl=en
==============================================================================

== 1 of 1 ==
Date: Mon, Apr 25 2011 8:48 am
From: SRAVANTHI LOVE

==============================================================================
TOPIC: Really "need to" replace older CATV cables? Would my cableprovider
really filter my line against my will?
http://groups.google.com/group/sci.electronics.repair/t/31e43b6766887486?hl=en
==============================================================================

== 1 of 2 ==
Date: Mon, Apr 25 2011 9:31 am
From: Jreality

One thing that I'm wondering....with regard to the technician claiming
that the cable company would slap a filter on an individual residence,
or group of them, if any ingress is being introduced into their system
by those homes...it seems to me that would prove that they don't
really have a fiber optic system as they claim. In other words, lets
say it's really true that my cables are pulling in some background
noise. If they're so darned concerned about ingress affecting their
precious little cable network (ha!), then it's likely because they
don't really have a fiber optic network from the pole and beyond as
they imply/claim they have. I'm failing to understand how, if there
really is fiber at the pole and beyond, then the ingress would survive
the conversion from a CATV Coax signal to fiber optic signal.

== 2 of 2 ==
Date: Mon, Apr 25 2011 10:32 am
From: "William Sommerwerck"

Even in a fiber-optic system, at some point the signal has to be converted
to RF for your TV or set-top box.

I don't know if there are systems that remain optical all the way up to the
set-top box.

==============================================================================
TOPIC: Mopar model 812 car radio, (early 1950's Chrysler product)
http://groups.google.com/group/sci.electronics.repair/t/3135639c17d6af1d?hl=en
==============================================================================

== 1 of 1 ==
Date: Mon, Apr 25 2011 1:51 pm
From: Meat Plow

On Sun, 24 Apr 2011 23:44:39 -0400, Michael A. Terrell wrote:

> Meat Plow wrote:
>>
>> On Sun, 24 Apr 2011 15:23:00 -0400, Michael A. Terrell wrote:
>> >
>> > A lot of old car radios used a 262.5 KHz IF to prevent image
>> > problems
>> > at 910 KHz. 262.5 KHz puts them all out of band.
>>
>> Old being before what year? I was just a young pup learning back in the
>> 70's so I don't recall a 262 IF. Probably too much LSD later on.
>
>
> Delco was still using 262.5 in the early '70s. I could repair most
> of their mid '60s to mid '70s AM radios in less than 15 minutes. Some
> took less than 5 minutes. I still hve most of the H.W. Sams AR series
> manuals. The cheap Japanese radios used either 450 or 455 KHz IFs,
> which caused problems on 900 or 910 KHz.

Well that makes sense. I got pretty good on the Delco stuff. Mostly bad
tubes, suppressor caps, stuck vibrators, things of that nature. Tweaking
the receiver I usually did by ear going through each stage from start to
finish. Then the antenna trimmer once it was back in the vehicle. I'm
sure I have an old tube radio and a few parts up in the attic. Used to
have one on my bench for music.

--
Live Fast Die Young, Leave A Pretty Corpse

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