Digest for sci.electronics.repair@googlegroups.com - 24 updates in 7 topics

curls <borskyc@yahoo.com>: May 30 10:08PM -0700

On Sunday, May 29, 2016 at 2:08:11 PM UTC-4, Dave Platt wrote:
> In article <edc77ec8-cedd-4e17-b1f8-7c0c9da95b93@googlegroups.com>,
 
Wow Dave, thanks for all the ideas!
 
Any idea in brick and mortar where I can buy 99%?
 
I'd also like to find something that won't leave lint like a qtip has.
 
I've cleaned and re-tested and it's definitely doing better! It's picking up disks from the library in 1 to 3 tries that were taking 10 or 20 tries. It plays homemade but takes a while to pick them up. I didn't check if they're CD+R or CD-R. (I always used +, but these weren't all made by me.)
 
I think I'd stick with cleaning the lens area for now, since the spiraly thing looks clean, and I can imagine how easily I could damage something. I'll tuck away the ideas though, in my tool chest for projects. I was thinking I'd try that idea of cutting off to get the reader further near the outside just to take a good look, but then it will have a disk in it. I wasn't able to get that disk out by hand.
 
I had no idea CD books are done with a less expensive method similar to home burned. Of course, I hope this isn't all indicative of a weakening laser beam. If the cleaning is helping, and I know it was a smoker's car... so maybe it's just a little haze on it. I just pulled out some professional music CDs tonight. I'm not seeing a difference in acceptance rate, so that's a good sign. Of course some of these bands aren't big and may have burned their own CDs.
 
I've just done a bunch more wiping with the 91% tonight, so maybe I'll try it again before hunting down more.
 
On the wire harness, I nicked one of the wires (very tiny spot) trying to get that thing off (even the dealer service person had trouble. For testing it doesn't matter, but I'd like to patch when I put it all back together. I'm thinking a touch of white lithium on the tiny little bare exposed nick will do well enough. There's no remote way to wrap electric tape around that small a wire kind of near the casing.
 
Thanks for all the education!!
curls <borskyc@yahoo.com>: May 30 10:10PM -0700

Called CVS and a rather sleepy pharmacist staff said they don't have 99%.
curls <borskyc@yahoo.com>: May 30 10:20PM -0700

On Sunday, May 29, 2016 at 4:19:42 PM UTC-4, Jeff Liebermann wrote:
> with what the digital camera can see from another CD player.
 
> Most common problem I've seen on vehicle CD players is "smoke" on the
> lenses and mirrors.
 
Thanks Jeff!
 
I thought I'd included the make and model originally. Must have been in the email to Sam. It's 2012 Mazda 3 iGT Hatch.
 
I don't know what particular unit it's considered to be. It is part of the radio console. The photos were after I got it out of the console and on it's own, and took a holder off so it's possible to get into the lens. Sure is hard to get good photos of the insides...
 
I know this car was a smoker's before me for 4 years. It didn't smell when I bought it, but there's been evidence since. So if most of the time problems have been smoke on the lens, do you mean actual smokers? It'd been hopeful for me, if that's the case.
 
Can you see in the photos, where the glass mirror would be? I know it looks like glass not a mirror, but I can't spot any place that could be it. Is it usually right near the lens? I can't easily take off that metal piece that's over the where the lens is, so it's hard to get under or into the lens area beyond the lens itself.
 
Taking a photo sounds like a good idea. It'd be very hard to take a photo since it has to be in the box, where the beam isn't directly visible. Maybe the more cleaning that I've done will do the trick.
 
Thanks for your help!
Ralph Mowery <rmowery28146@earthlink.net>: May 31 09:58AM -0400

In article <2017a819-60e3-44a8-9fa9-8172b8dc4afc@googlegroups.com>,
borskyc@yahoo.com says...
 
> Wow Dave, thanks for all the ideas!
 
> Any idea in brick and mortar where I can buy 99%?
 
> I'd also like to find something that won't leave lint like a qtip has.
 
I have looked and asked at several drug stores for the 99% but none had
it. Finally ordered some off Amazone for 3 pintes for about $ 15.
Postage would make it more, but needed soe other things so got free
shipping.
 
YOu might look for some of the things that look similar to qtips but
have a sponge type of tip on them in the makeup section. I usually use
some of the Kemwipes that leave almost no fibers . You may want to try
some of the cleaning tissues for glasses that have alcohol already on
them if this is just a one time thing.
curls <borskyc@yahoo.com>: May 31 07:15AM -0700

Found the 99% -- at Micro Center. (Maybe Best Buy or Radio Shack carries it too.)
Michael Black <et472@ncf.ca>: May 31 10:52AM -0400

Jeff Liebermann <jeffl@cruzio.com>: May 31 08:17AM -0700

On Mon, 30 May 2016 22:20:43 -0700 (PDT), curls <borskyc@yahoo.com>
wrote:
 
 
>> Most common problem I've seen on vehicle CD players is "smoke" on the
>> lenses and mirrors.
 
>It's 2012 Mazda 3 iGT Hatch.
 
My point is that the drive is NOT easily replaced. No clue on parts
but unless the CD drive mechanism can be identified, finding
replacement parts is going to be difficult.
 
Read the repair faq section on "CD players in vehicles".
 
>I know this car was a smoker's before me for 4 years.
 
Bingo. 90% rubbing alcohol works well to remove the tar.
 
>So if most of the time problems have been smoke on the lens, do you
>mean actual smokers? It'd been hopeful for me, if that's the case.
 
Yes, but there are plenty of other sources of oil, grease, tar, soot,
and such. Just look at the windows. Do they remain perfectly clear
when you're driving? Of course not. Well, some of that also gets
into the CD player and makes the optics looks much like your
windshield.
 
>Can you see in the photos, where the glass mirror would be?
 
I have no idea. The photos are too small and cover too large an area.
Look for something like this:
<http://g01.a.alicdn.com/kf/HTB1Cm2ZKXXXXXXWXFXXq6xXFXXXJ/Original-Replace-For-font-b-Pioneer-b-font-DEH-P7400MP-font-b-CD-b-font-font.jpg>
The mirrors are behind the lens.
<http://hyperphysics.phy-astr.gsu.edu/hbase/audio/cdplay.html>
 
>take a photo since it has to be in the box, where the beam isn't
>directly visible. Maybe the more cleaning that I've done
>will do the trick.
 
I don't take a photo. All I do is check if there's anything coming
out of the laser or if it looks wrong.
<https://www.youtube.com/watch?v=Df70YVAg-iI>
Fast forward to 2:10 for what it looks like. Not all digital cameras
can see 780nm light. (DVD are 650nm and BluRay are 405nm).
 
There are also photo diodes on a stick that can be used to measure the
laser output. For some odd reason, I can't find the magic buzzwords
and URL. Anyone?
 
Oh crap. Power outage... save, post, and run...
 
 
--
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
Jeff Liebermann <jeffl@cruzio.com>: May 31 08:38AM -0700

On Tue, 31 May 2016 07:15:41 -0700 (PDT), curls <borskyc@yahoo.com>
wrote:
 
>Found the 99% -- at Micro Center. (Maybe Best Buy or Radio Shack carries it too.)
 
Alcohol is hydroscopic (absorbs moisture from the air). Your 99% will
go down to 91% if you leave the bottle open. Fortunately, it takes
some time so you don't need to be fanatical about replacing the cover.
<https://en.wikipedia.org/wiki/Azeotrope>
Note that 70% alcohol is what you want for a disinfectant because some
water is needed to kill of hydrophylic bugs.
 
I should probably buy some 99% alcohol for lens cleaning, but have
been getting away with using the 91% stuff without streaking.
 
<http://www.ebay.com/sch/i.html?_nkw=99%25+alcohol>
Ugh... about $8/pint
 
--
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
Ralph Mowery <rmowery28146@earthlink.net>: May 31 12:51PM -0400

In article <edbrkbttgbpgfm6agsmmp526nn7huhkgbf@4ax.com>,
jeffl@cruzio.com says...
> been getting away with using the 91% stuff without streaking.
 
> <http://www.ebay.com/sch/i.html?_nkw=99%25+alcohol>
> Ugh... about $8/pint
 
Found some 99% on Amazon for $ 14.05 for 3 pint contaniers.
 
http://www.amazon.com/99-Isopropyl-Alcohol-Antiseptic-
Solution/dp/B00BWYNIDO?ie=UTF8&psc=1
&redirect=true&ref_=oh_aui_detailpage_o01_s00
 
Need to order other things to make up about $ 50 total for free
shipping. As my wife likes certain Yuban Gold coffee that is not in
the local stores any more, I ordered lots of that and the 99% for the
free shipping.
 
It seems to be 99% as I put equal ammounts of that and some Walmart 90%
in some open containers (about half a teaspoon) and kept checking on it.
The 90% still had something left in it after all the 99% was gone or
almost gone.
"Mark Zacharias" <mark_zacharias@sbcglobal.net>: May 31 07:36AM -0500

"tom" <tmiller11147@verizon.net> wrote in message
news:nid3rg$l4b$1@dont-email.me...
 
> <jurb6006@gmail.com> wrote in message
> news:8168144b-e201-4fec-bdd5-158f8a0c0a2f@googlegroups.com...
> I wish Jim Yanik was around.
 
Uh-Oh. Something happen to Yanik?
 
 
Mark Z.
"jfeng@my-deja.com" <jfeng@my-deja.com>: May 30 11:25AM -0700

On Monday, May 30, 2016 at 8:30:43 AM UTC-7, M Philbrook wrote:
 
> a Graphic EQ.
 
> Jamie
...which you can find on eBay, many under US$20 (and even cheaper at a ham swap).
Black Iccy <Daedelus@whereamIinvalid.com>: May 31 08:15AM +1000


>Result? A smoother, less intrusive
>sound at background or concert-
>hall levels.
 
Smoother than what?
 
Twin-T, RC filter.
thekmanrocks@gmail.com: May 30 04:23PM -0700

Black Iccy wrote: "Smoother than what?"
 
 
https://upload.wikimedia.org/wikipedia/commons/thumb/4/47/Lindos1.svg/2000px-Lindos1.svg.png
 
Read up on it.
"Gareth Magennis" <soundserviceleeds@outlook.com>: May 31 01:27AM +0100

wrote in message
news:4ce17090-787d-4c15-8515-4d09abacc6f5@googlegroups.com...
 
This resistor is very simple. It will have
stereo RCA in and out, and 1/8" mini
in and out.
 
All it will do is attenuate 2.5khz by 3
dB, with a Q wide enough to modestly
affect frequencies from 1kHz up to 4kHz.
 
Essentially to mildly scoop out those
audio frequencies humans most readily
hear. One could plug a line source or
phone into it, and RCA out, IE, to a
stereo amp. One could use the built-
in tone controls('Bass', 'Treble'), to
tailor the ends of the bandwidth to
taste.
 
Result? A smoother, less intrusive
sound at background or concert-
hall levels.
 
What materials do I need?
 
 
 
 
 
 
You want a parametric EQ you can build yourself.
 
Good luck with that.
 
 
Gareth.
Black Iccy <Daedelus@whereamIinvalid.com>: May 31 05:00PM +1000


>Black Iccy wrote: "Smoother than what?"
 
>https://upload.wikimedia.org/wikipedia/commons/thumb/4/47/Lindos1.svg/2000px-Lindos1.svg.png
 
>Read up on it.
 
No use pointing me at a set of Fletcher-Munson curves.
I met those more than 60 years ago so if you think they're
a point of enlightenment for me. Wrong. Particularly wrong
because those curves are statistical averages for particular
known levels. If you're trying to produce a response contour,
those curves are not *it*. Turn up the volume a bit and your
ears will respond differently.
 
If you're trying to attenuate the mid-range audible levels
for yourself, then you're intensifying the effect. Possibly wrong.
 
If you think that a source has not had sufficient attention
by the recording engineer at the time and that he/she did
not endeavour to ensure a good result (one which you don't like)
so you alter the response that's for you to decide. The easiest
way is to build *nothing* and just raise the trevble and bass
controls a fraction - same result.
thekmanrocks@gmail.com: May 31 04:45AM -0700

On Tuesday, May 31, 2016 at 3:00:18 AM UTC-4, Black Iccy wrote:
> so you alter the response that's for you to decide. The easiest
> way is to build *nothing* and just raise the trevble and bass
> controls a fraction - same result.
________________
 
The point is, doing so sounds good to
me. There are two audible "muddy zones"
in the audio spectrum, to either side
of 1kHZ: between 150-250Hz, and between
2-4kHz. A low-Q modest scoop(2-3dB) in
those areas cleans things right up,
whether I'm listening through full-size
speakers, headphones, even if I'm
listening through those dreaded Apple
Buds that ship with every iPod.
 
 
All I need is a filter for at least the
higher "mud"(2-4khz) that can fit inline
between my iPod and the receiver or
amp it's connected to, or inline between
the CD player and same amp. I have a
15band graphic EQ in my listening system,
but need something a *little* less clunky
for mobile purposes. A filter, if one can
be built that's a little bigger than a
Zippo lighter, would do the trick.
 
 
By modestly reducing those areas, I don't
need to "raise the treble and bass". Plus
I've already bought some gain by said
reduction. And even though I looked at
the graph, the area of upper mid-range
I need to reduce that sounds good to
me is slightly lower, between 1-3kHz.
As you said, the published curves represent
averages, so they may not work for
everyone.
jurb6006@gmail.com: May 31 02:37AM -0700

>Turned on headlights - 15.0 steady
>Turned on headlights and turn signal - 15.2-15.8 cycling
>No lights, turn signal on - 15.2-15.8 cycling "
 
Does not sound to me like you need an alternator. As much as old timers may disagree, 15 volts it just about where you want it. These newer batteries can take it. To charge the old batteries of the 1960s that hard would cause too much water loss and you'd have to feed it every couple of day. Not no mo.
 
If you are charging at or near 15 volts and have trouble starting or anything you either have a bad battery or a fault in the system draining the battery. And don't forget, newer cars do drain the battery constantly to maintain memory.
Michael Black <et472@ncf.ca>: May 30 01:44PM -0400

"jfeng@my-deja.com" <jfeng@my-deja.com>: May 30 11:33AM -0700

> With TV, they wasted it. They went digital because NTSC takes too much
> bandwidth and has limited resolution. The problem is they cannot come
> up with any decent programming anymore.
Digital would take more bandwidth, except they use compression to reduce the amount of data sent. In the 1950s, there was not enough computing power in the whole world to do the compression and decoding in real time.
vjp2.at@at.BioStrategist.dot.dot.com: May 31 01:48AM

Wow! incredible answers, thanks
 
 
- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]
isw <isw@witzend.com>: May 30 08:55PM -0700

In article <f98233c5-9087-46e8-9e87-149ee79955d2@googlegroups.com>,
> captioning, ghost cancelling reference and who knows what else.
 
> Man's innate lust to cram as much as possible into any given bandwidth.
 
> With TV, they wasted it.
 
Actually, NTSC color makes pretty good use of bandwidth when you're
constrained to all-analog, vacuum-tube technology. When it was
introduced, compatible color was right at the cutting edge of (or maybe
a bit beyond) technical feasibility for commercial (not to say consumer)
electronics.
 
Isaac
jurb6006@gmail.com: May 31 02:26AM -0700

>"Actually, NTSC color makes pretty good use of bandwidth when you're
>constrained to all-analog"
 
Right, but that is not what I meant. I meant none of this shit is worth watching. When I was a kid and we had like five channels we actually had to have a discussion on what to watch.
 
Now hot only are there more TVs in the house than people, we got like 500 channels. There used to be shows that were entertaining, even though they were kinda like - junk. They were entertaining. Now we are relegated to watching people remodel houses or something, or Gordon Ramsay bitching out restaurant owners or some retired detective describing a 35 year old case, with re-enactment of course. Most other shows it looks like they let an eight year old kid work the camera, I mean they do EVERYTHING cameramen were taught not to do. It is fucking unwatchable.
 
In the 1960s and 1970s having a TV was a status symbol almost. Now, it has gotten so bad that NOT having one is, almost. Or at least leaving it turned off.
 
>introduced, compatible color was right at the cutting edge of (or >maybe
>a bit beyond) technical feasibility for commercial (not to say >consumer)
>electronics."
 
Actually it could not be beyond since it worked. It redefined the cutting edge. Color TV is one of the few things the US can claim as its own invention. Other countries came later, albeit with better systems, but I am pretty sure we were first.
 
I am not sure about FM stereo. Never really looked into it. I know that in Europe they use less modulation and thus less bandwidth. The de-emphasis is 50 uS not 75. I also had the US and European versions of the same album (Golden Earring - Moontan) and their version was cut with alot less groove modulation and had a huge leadout, putting most of the music where the groove velocity was greater and tracking error less. It sounded considerably better. I mean ALOT better.
 
Seems like the US is all about loud. More modulation, more up compression, and even other tricks to sound louder. Idiots will put their graphic equalizers full tilt up, and have no idea how to properly use a dynamic range expander like a Pioneer RG-1 or RG-2. They think the right way is to turn the input level all the way up. Look asshole, if it was meant to be all the way up all the time why did they even put a control there ?
 
But that is my opinion after much observation. LOUD is the "American" way. Wasn't it the US came out with laws about reporting the power output of amps ? I guess other countries have the same but that seems like something we probably did first.
vjp2.at@at.BioStrategist.dot.dot.com: May 31 01:52AM

THanks. I seem to be able to avoid the problem by not interrupring the
cycle. If I reset the spring timer from 20 min to 40 min it gets stuck
at 40 min. If I let it finish then reset it, it seems not to stick (as much?)
 
I've been replacing the switch when it get stuck, every thre years or so,
except a friend with an entire building full of them (running two decades)
tells me to timer isn't the problem, I am.
 
 
- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]
Tekkie® <Tekkie@comcast.net>: May 30 03:51PM -0400

Danny DiAmico posted for all of us...
 
 
> I put the board in the washing machine, and it worked.
 
What kind of detergent did you use?
 
--
Tekkie
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Digest for sci.electronics.repair@googlegroups.com - 13 updates in 5 topics

Jeff Liebermann <jeffl@cruzio.com>: May 29 09:57AM -0700

>and I think a few, very few, variable. The wider bandwidth results
>in much lower distortion. However then there is more noise and
>you need a stronger signal.
 
What little I've done with broadcast FM was at various radio stations
and designing some low end receivers. That was also long ago, so I'm
fairly well behind on the technology. However, if "high end" means
"high price", I've fixed a few of these systems:
<http://www.elanhomesystems.com>
 
If you've ever swept a decent analog FM receiver, you may have noticed
that the IF bandwidth is much wider than the occupied bandwidth
(200KHz) of the signal. In order to keep the group delay fairly
constant within the IF bandwidth, this was necessary. That meant that
while the audio was very good quality, the receiver would pickup junk
from adjacent channels. Sensitivity is limited by the receiver front
end and is unaffected by the wider bandwidth.
 
Roll forward a few decades and we are now blessed with all digital
receivers. The best example is the Sony XDR-F1HD tuner:
<http://ham-radio.com/k6sti/xdr-f1hd.htm>
<http://www.amazon.com/Sony-XDR-F1HD-Radio-Discontinued-Manufacturer/dp/B00168Q248>
These typically sell on eBay for $150 to $250 or $500 with some
necessary modifications. Seems to be a demand:
<http://www.ebay.com/sch/i.html?_from=R40&_nkw=XDR-F1HD&LH_Complete=1&LH_Sold=1>
The difference is that this receiver has a "brick wall" digital IF
filter that doesn't need to be excessively wide in order to get low
group delay and low distortion. The narrower bandwidth is also good
for reducing much of the alternate channel noise produced by IBOC (HD
Radio) signals.
 
Meanwhile, the lower end FM receivers are also deriving benefits from
digital IF and demodulators. The Sony tuner uses an NXP/Philips
SAF7730 chip while most of the low end stuff uses various Silicon Labs
AM/FM chips:
<http://www.silabs.com/products/audio/fm-am-receiver/>
<http://www.silabs.com/products/audio/fmreceivers/>
Basically, it's almost an SDR (software defined radio) with most
everything in a single chip. Tecsun uses these chips in their various
radios. Plugged into a proper audio amp and speakers, they sound very
good, with little IBOC junk from the adjacent channels. (Note: Not
all Tecsun radios use digital receiver chips).
 
>Actually it is all going digital soon, a couple of countries are in
>the process of that right now.
 
No, it's not, at least in the USA. The FCC, in its infinite wisdom,
has endorse exactly one proprietary and expensive standard (IBOC)
totally owned and licensed by iBiquity. As usual, half measures don't
work. In this case, the broadcast industry wasn't quite sure if they
were going to commit to doing IBOC, so instead of 100% digital FM,
iBiquity was forced to provide the half ass analog/digital compatible
system that we're cursed with today. Incidentally, the failed AM
stereo system following a similar life cycle demonstrating that the
FCC and the industry doesn't learn from their expensive mistakes.
 
In 2012, a made a graph of the number of HD Radio stations in the SF
Bay area and in the USA.
<http://802.11junk.com/jeffl/crud/hd-radio-stations-calif.jpg>
<http://802.11junk.com/jeffl/crud/hd_radio_stations.jpg>
<http://www.stateofthemedia.org/2013/audio-digital-drives-listener-experience/9-number-of-stations-dropping-hd-outnumber-those-adopting-in-2012/>
There's actually been a decrease in stations, that have unplugged
their HD Radio equipment since 2012 but I don't have numbers handy.
 
I know little (or nothing) of what's going on with DAB (digital audio
broadcasting) as it's not used in the USA:
<https://en.wikipedia.org/wiki/Digital_audio_broadcasting>
 
--
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
dplatt@coop.radagast.org (Dave Platt): May 29 11:13AM -0700

In article <f8dd99f8-b2a4-4800-8fd2-de2d449496e1@googlegroups.com>,
 
>I saw a modification for it and surprising to me is it was not something to cut the IF bandwidth, it was
>strictly in the ratio detector. It seems the newer quadrature detectors don't have much of a problem with
>this, so far I saw.
 
The digital noise is commonly a problem as the result of the way
stereo demultiplexing works. The higher-frequency components of the
FM detector's output are mixed against the 38 kHz local oscillator,
thus doing an AM demodulation of the L-R subcarrier band which lies on
either side of 38 kHz.
 
Many MPX decoders use a simple switching-mixer architecture, and these
will end up detecting both the signal around 38 kHz, but also whatever
is present in the neighborhood of the third and fifth harmonic of 38
kHz. Since that's where the digital subcarriers often line, the
digital signal ends up as sideband noise in the L-R difference signal,
and (unless you switch the tuner to "mono") ends up in the left and
right channel audio.
 
There are a number of ways to fix this. One is to filter the FM
detector output signal before it goes to the MPX chip... either a
low-pass filter (knee somewhere about 60 kHz), or notch filters
centered on the odd harmonics of 38 kHz, or both.
 
Another approach is to demodulate the MPX signal using a design which
is inherently not sensitive to the 38 kHz harmonic regions... e.g. a
true multiplying mixer using a 38 kHz sinewave local oscillator
(rather than a square wave or switching design), or a Walsh-function
decoder using a stepped wave which has no 3rd or 5th harmonic
content (some Sansui tuners do this).
 
Modern DSP-based MPX decoders could do any of these.
 
http://ham-radio.com/k6sti/hdrsn.htm has a nice overview of the
problem and solutions.
Jeff Liebermann <jeffl@cruzio.com>: May 29 12:58PM -0700

On Sun, 29 May 2016 11:13:09 -0700, dplatt@coop.radagast.org (Dave
Platt) wrote:
 
>http://ham-radio.com/k6sti/hdrsn.htm has a nice overview of the
>problem and solutions.
 
That article is on HD Radio (IBOC, iBiquity, dismal radio, etc) and
not about conventional FM stereo. While the mechanism for generating
the noise that you don't want to hear is similar, the technology,
solutions, and sources of noise are quite different. For example,
there's no mixing required for the excessive occupied bandwidth of
IBOC to ruin your day.
 
Incidentally, Brian Beezley has written several other articles on HD
Radio and tuners:
<http://ham-radio.com/k6sti/>
See "HD Radio" section at lower right and various equipment reviews at
the upper right.
 
--
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
isw <isw@witzend.com>: May 29 10:38PM -0700

In article <f8dd99f8-b2a4-4800-8fd2-de2d449496e1@googlegroups.com>,
 
> But bear in mind there were adverse implications. When it was simple "store
> cast allocation" it was at 76 KHz, locked to the 19 KHz stereo pilot. The
> deviation was very low and did not produce much in the way of sidebands.
 
SCA usage predates FM stereo. Originally there were two subcarrier
frequencies: 43 kHz and 76 kHz. As stereo broadcasting became popular,
the 43 kHz channel was abandoned due to interference. While some
broadcasters may have synchronized the 76 kHz frequency with the 19 kHz
stereo pilot, this was not required. Plus, since the SCA signal itself
is frequency modulated, locking it to the pilot would not accomplish
much in any case.
 
Isaac
jurb6006@gmail.com: May 30 09:43AM -0700

Interesting, in fact everybody, interesting.
 
Next we need a thread on what all they crammed into the NTSC TV signal. Like PRO audio which was another SAP essentially, the VITS or VIR, closed captioning, ghost cancelling reference and who knows what else.
 
Man's innate lust to cram as much as possible into any given bandwidth.
 
With TV, they wasted it. They went digital because NTSC takes too much bandwidth and has limited resolution. The problem is they cannot come up with any decent programming anymore.
 
In other words, the resolution doesn't matter if there's nothing to watch. I don't need 2,000 line resolution to watch Gunsmoke. Just like I don't need 24 bit/96 KHz sampling to listen to music from the 1960s.
thekmanrocks@gmail.com: May 29 11:43AM -0700

This resistor is very simple. It will have
stereo RCA in and out, and 1/8" mini
in and out.
 
All it will do is attenuate 2.5khz by 3
dB, with a Q wide enough to modestly
affect frequencies from 1kHz up to 4kHz.
 
Essentially to mildly scoop out those
audio frequencies humans most readily
hear. One could plug a line source or
phone into it, and RCA out, IE, to a
stereo amp. One could use the built-
in tone controls('Bass', 'Treble'), to
tailor the ends of the bandwidth to
taste.
 
Result? A smoother, less intrusive
sound at background or concert-
hall levels.
 
What materials do I need?
Rasta Robert <rr@dds.nl.ReMoVe_ThIs.invalid>: May 30 03:20PM

> sound at background or concert-
> hall levels.
 
> What materials do I need?
 
So not a resistor, but a filter,
a notch or band stop filter to be
precise.
You will at least need resistors and capacitors,
possibly one or two coils.
 
<https://en.wikipedia.org/wiki/Band-stop_filter>
<http://www.radio-electronics.com/info/circuits/rc_notch_filter/twin_t_notch_filter.php>
<http://www.hobby-circuits.com/circuits/audio/audio-filter/590/rc-notch-filter-twin-t>
<http://www.instructables.com/id/Passive-Filter-Circuits/>
 
Making it a passive circuit will also
attenuate the signal level, so you
might need some active amplification
in it to recover that.
 
<http://www.circuitsstream.com/2013/06/simple-notch-filter-uses-operational.html>
<http://www.radio-electronics.com/info/circuits/opamp_notch_filter/opamp_notch_filter.php>
M Philbrook <jamie_ka1lpa@charter.net>: May 30 11:38AM -0400

In article <4ce17090-787d-4c15-8515-4d09abacc6f5@googlegroups.com>,
thekmanrocks@gmail.com says...
> sound at background or concert-
> hall levels.
 
> What materials do I need?
 
a Graphic EQ.
 
Jamie
hrhofmann@att.net: May 29 02:08PM -0700

Sorry, but your post doesn't make any sense.
 
If it is a mechanical timer, when you set the time, it starts a clockworks mechanism that closes contacts for the length of time set, and then opens the contacts, to shut of the bathroom fan, for example. If it is a purely electrical type of timer, a motorized clock does the timing for opening a set of contacts and shutting off the ventilating fan.
dplatt@coop.radagast.org (Dave Platt): May 29 10:58AM -0700

In article <edc77ec8-cedd-4e17-b1f8-7c0c9da95b93@googlegroups.com>,
>My car's CD player reports Check CD and ejects many CDs. I've managed to get the radio out of the car, and
>opened it until I can now see the laser lens.
 
>I plan to clean with Qtip and isopropyl alcohol 91%.
 
Use a photographer's "puffer brush" first (a rubber squeeze-bulb with
a soft-bristle brush on the end). Brush the lens very lightly and
then puff it gently with air. This will dislodge and remove the worst
of the dust.
 
I would recommend getting electronics-grade isopropyl rather than
using 91% commercial type... you really want something as pure as
possible so that it won't leave a residue.
 
>Is there anything else I can clean? Or lube with white lithium?
 
The only other thing I see which you might address, is the metal rail
on which the optical sled moves in and out. If I'm seeing what I
think I'm seeing, it's the silver metal rod, which has something that
looks like a helical spring wound around it.
 
If this rail is dirty, or if it has old lubricant which has gotten
gummy, the sled would be unable to move smoothly and the
laser/photodiode mechanism would have trouble following the spiral
track on the CD's data layer.
 
You might be able to clean it (very carefully) using a small brush
with a suitable solvent (electronics-grade isopropyl, or "white
spirit" (naptha), and then relubricate (a *small* amount of sewing
machine or watchmaker's oil... "light machine oil"). Do *not* use
3-in-1 or WD-40! Be very careful not to get either the solvent or the
oil on other parts of the mechanism, or force or bend anything.
 
Due to the presence of that helical spring or coil (whatever it is I
think I'm seeing) this is likely to be a tricky process. Don't try it
at all unless you're willing to take the risk of destroying the whole
thing.
 
If you can get a long disc (70-80 minutes) to play all the way to the
end, and then cut the power without pressing "STOP", you'll probably
find that the laser sled has moved all the way to the outer diameter
of the CD. This may leave the "rail" exposed, and easier to access
and clean.
 
You might find that some gunk has built up near the inner diameter of
the rail. This could "bind" the optical sled when it tried to read
the disc's table of contents, which is written right at the inner
diameter of the CD data area.
 
>the CDs have trouble and will eject with Check CD repeatedly. Then on one of the re-inserts, they'll read.
>The CDs are books on CD from the library. I've washed most of them, and they look good (not scratched or
>dirty).
 
Books-on-CD are commonly "burned" CD-Rs, rather than "pressed" CDs.
The reflectivity contrast of their data patterns is about half that of
pressed CDs, which means that the laser/photodiode has a weaker signal
to follow. It's fairly common for failing CD players to start
rejecting CD-Rs, while they can still track commercial "pressed" CDs.
 
This sometimes (often?) means that the laser diode is approaching its
end of life - the laser output is declining, and the photodiode system
is getting a weaker and weaker signal from the disc.
 
The only real cure for this is to replace the laser diode (often the
whole optical assembly), and then recalibrate the laser drive and the
tracking. This is definitely possible but may not be economically
worthwhile. There are probably YouTube videos which show the
procedure.
 
It's sometimes possible to turn up the laser drive current, but this
is a *very* temporary hack... the higher current just makes the diode
fail all that much sooner.
Jeff Liebermann <jeffl@cruzio.com>: May 29 01:19PM -0700

On Sun, 29 May 2016 08:53:43 -0700 (PDT), curls <borskyc@yahoo.com>
wrote:
 
>My car's CD player reports Check CD and ejects many CDs.
 
Does the CD player have a maker and model number?
Your photos kinda look like the player is part of the vehicle console
and not a seperate unit. Perhaps the vehicle maker and model might
help.
 
This might help:
<http://www.repairfaq.org/sam/cdfaq.htm>
 
With CD lasers, I like to use my digital camera to "see" the IR output
of the laser. To determine if it's lacking in brightness, compare it
with what the digital camera can see from another CD player.
 
Most common problem I've seen on vehicle CD players is "smoke" on the
lenses and mirrors.
 
--
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
"Snuffy \"Hub Cap\" McKinney" <Snuffy-Hub-Cap@Livebait-McKinney.com>: May 29 10:27AM -0700

> It can be something as simple as a slipping belt. I'd tighten or
> replace it before rebuilding the alternator. Yes, I've seen it happen
> more than once. .
---
 
Thanks for all the help. Still trying to find the time to spend TS...
 
Last night I was able to catch it cycling just now. No time to check at the alternator tonight, but here's some voltages at the battery terminal.... Turn signals seems to cause the cycling tonight, although I have seen it cycling with just the lights on.
 
Battery with engine off - 13.6
Turned engine on
Idling with no lights - 15.0 steady
Turned on parking lights - 15.0 steady
Turned on headlights - 15.0 steady
Turned on headlights and turn signal - 15.2-15.8 cycling
No lights, turn signal on - 15.2-15.8 cycling
Sjouke Burry <burrynulnulfour@ppllaanneett.nnll>: May 29 08:49PM +0200

On 29.05.16 19:27, Snuffy "Hub Cap" McKinney wrote:
> Turned on headlights - 15.0 steady
> Turned on headlights and turn signal - 15.2-15.8 cycling
> No lights, turn signal on - 15.2-15.8 cycling
 
That sounds like a defective regulator or generator
going on/off.
Which would suggest the two voltages.
Bad wiring would produce a different pattern.
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Digest for sci.electronics.repair@googlegroups.com - 14 updates in 6 topics

curls <borskyc@yahoo.com>: May 29 08:53AM -0700

My car's CD player reports Check CD and ejects many CDs. I've managed to get the radio out of the car, and opened it until I can now see the laser lens.
 
I plan to clean with Qtip and isopropyl alcohol 91%.
 
Is there anything else I can clean? Or lube with white lithium? Photos:
http://postimg.org/gallery/13v02pwm6/
I can't spot a glass surface (mirror). Is the white rotating disk in the middle good to clean? Can the lens unit be rotated on the spindle so I can wipe the part close to the center (in case there's dirt in there - although it looks clean)?
 
----
Additional, here's details on what's happening that's in error. Does it indicate anything?
 
There are disks that consistently read without trouble. The same disk will work every time. It's been only 4 out of about 20, but it's the same 4 CDs every time that get initially picked up just fine. The rest of the CDs have trouble and will eject with Check CD repeatedly. Then on one of the re-inserts, they'll read. The CDs are books on CD from the library. I've washed most of them, and they look good (not scratched or dirty).
 
Once read, if I turn off the radio, when I restart it goes back to Check CD. However they don't physically eject and will keep spinning around reporting a Check CD, until finally at some time they'll start reading.
 
All CDs once read, will continue fine until the end of the CD or until I turn the radio off. (Pausing works without trouble and the CD starts right up.)
 
Twice maybe three times in 20 or so hours of playing there's been a skip later in a CD. However it's always repeatedable at exactly the same spot, and there's at least once, been dirt on the CD to match (I didn't look the other times).
 
Thanks!!
vjp2.at@at.BioStrategist.dot.dot.com: May 28 11:26PM

Are such radios sold in the USA via the internet? Is the station really
"fixed"? Someone gave my uncle a radio which is said to have a special
"chip" that receives a Greek radio station. He mentioned to me that years ago
he had another one that suddenly switched to a Philipine station and he gave
it to a Filipino colleague. Amazon and Alibaba have such Metrosonix radios
but not station specific, but also do not seem to allow being sold in the
USA. THe search terms I used were <SCA FM radio>.
 
- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]
Jeff Liebermann <jeffl@cruzio.com>: May 28 06:33PM -0700

On Sat, 28 May 2016 23:26:44 +0000 (UTC),
>USA. THe search terms I used were <SCA FM radio>.
> - = -
> Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
 
Yes, but not quite in the way you describe:
<https://en.wikipedia.org/wiki/Subsidiary_communications_authority>
In the USA, additional SCA carriers used to be quite common on most FM
stations. They were used to subscription handle background music
(MUZAK), commercial free radio, and all kinds of data broadcasting
(stocks, paging, sports scores, traffic reports, etc).
 
Most of that died starting in about 2002 with the introduction of
digital FM radio.
<https://en.wikipedia.org/wiki/HD_Radio>
The IBOC signals occupy the spectrum just outside of the normal FM
stereo signals formerly occupied by SCA sub-carriers. SCA and IBOC
cannot coexist on the same frequency.
 
In the USA, FM broadcast channel spacing is 200KHz. Stations licenses
in a given geographic area are assigned on alternate 200KHz slots
giving broadcasters a 200KHz guard band to allow for junk receivers
with rather wide IF bandwidth. SCA sub-carriers never went above
about 80Khz, so there was no increase in occupied bandwidth. IBOC
changed all that by grabbing all the spectrum between +/-100kHz and
+/-200KHz:
<http://802.11junk.com/jeffl/crud/KCSM.jpg>
Such an IBOC transmitter is now transmitting on top of the adjacent
channels frequency. If the adjacent channel is not occupied, no
problem. If there's a station there, big problem.
 
In some parts of Europe, FM stations are assigned on 100KHz channel
spacing, making both SCA and IBOC an impossibility. I don't know
which countries are like that.
 
--
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>: May 28 10:59PM -0400

jurb6006@gmail.com: May 28 10:13PM -0700

>about 80Khz, so there was no increase in occupied bandwidth. IBOC
>changed all that by grabbing all the spectrum between +/-100kHz and
>+/-200KHz: "
 
But bear in mind there were adverse implications. When it was simple "store cast allocation" it was at 76 KHz, locked to the 19 KHz stereo pilot. The deviation was very low and did not produce much in the way of sidebands.
 
I don't know how familiar you are with high end audio but there are tuners out there that can switch between narrow and wide band IF, and I think a few, very few, variable. The wider bandwidth results in much lower distortion. However then there is more noise and you need a stronger signal. But the ultimate THD at "full quieting" is actually enough I used to be able to hear it. But on weaker stations you might want the narrow IF bandwidth. I think a couple of vary rare high end tuners used variable, maybe Studer Revox or something. In the 1980s, GM car radios got so damn good I thought maybe they had it but after seeing the print (was VERY hard to get) I do not see it. I think the Delco 2000s are Schotz tuners but I don't know if they vary the IF bandwidth. Later car stereo designs wen into multiple antennae and front ends that switched, quite transient free actually, between up to four of them. Yup, four front ends. I seen it.
 
Now, this digital information bothers high fidelity tuners. they are coming out with modifications to the ones with the worst susceptibility. I mean even tuners built in the 1970s. Some of them were damn good. Now, the digital information makes for like "hash" or whatever, an unpleasant background noise.
 
I saw a modification for it and surprising to me is it was not something to cut the IF bandwidth, it was strictly in the ratio detector. It seems the newer quadrature detectors don't have much of a problem with this, so far I saw.
 
Of course next year they will probably try to put four sports video channels in an FM bandwidth and we just all have to buy new radios. Leave me out, I have all the music and movies I will ever need. Even porn. Well I got that from a buddy for whom I am providing an "offsite backup".
 
But there is no breaking the laws of physics. When you cram more into that carrier there is a cost. Either noise or distortion. Maybe both, or maybe you can take your pick. The distribution of harmonics in FM is a funny thing, it is not like AM which is simple. They go up high to insert their digital data and probably 85 % of the people do not notice, but then some do.
 
Actually it is all going digital soon, a couple of countries are in the process of that right now. That eans if you drive an older car you will need to but a convertor, or just play disks. Or AM. As far as I know they have no plans to fuck AM up anymore than they did with AM stereo. And that wasn't so bad because AM is not supposed to be high fidelity.
 
But when the transistion comes you will have like 500 stations.
 
Know what ? When I was a kkid we had like five TV stations and we had to sit down and talk about what we were going to watch. (before Star Trek...) We looked at a paper with the schedule on it. Actually we watched some of the movies they rated the worst lol, but that is not the point. Today with the cable there are 500 channels and nothing to watch.
 
Orwell - less is more.
Bruce Esquibel <bje@ripco.com>: May 29 11:28AM

> it to a Filipino colleague. Amazon and Alibaba have such Metrosonix radios
> but not station specific, but also do not seem to allow being sold in the
> USA. THe search terms I used were <SCA FM radio>.
 
I'd be kind of suprised if any of those stations were still active.
 
Here in Chicago, it was probably the early 90's that was the height of
popularity, I think there were 2 greek stations, one polish and 3 or 4
others that were probably used for pocket pagers (normally silent except for
bursts of tones or a data carrier).
 
The basic idea was the "broadcaster" would get the station from overseas
(probably via a C-Band dish/receiver) and rebroadcast it on someones sca
channel (an ordinary FM station set up for it). They would then rent the
modified radio for like $5 a month or sell you it with a "lifetime"
subscription for $100 or around there.
 
Usually the radios, which were cheap garbage imports, were fixed to the
primary channel by crazy glueing the tuning shaft or otherwise disabling the
tuner. The boards were just simple 4 wire things, power, ground, detector in
and audio out. Since they were meant as a dedicated service, there wasn't
any reason to make the radio work both ways, normal and special. These
were all handmade and varied quite a bit, depending on what make/models the
local wholesale importers had.
 
The adapters were numerous, the most basic/simple one used a PLL chip
(either NE565 or NE566, maybe) and off the shelf resistors and capacitors.
They usually worked well enough but had problems with leakage from the main
carrier. There was another design, I want to say MC1340 as the centerpeice
which had the best performance (dead quiet) but required custom rf coils and
oddball capacitors, still simple to build but upped the cost quite a bit.
 
In any case the boards were probably not even 2"x2" and were easily tucked
in somewhere, usually the battery holder (4xC or D cells).
 
As far as legality of them, although I don't think anyone considered them a
crime to own, you couldn't open up a cottage industry by building them and
selling them. There was no reason to stop anyone from making one, but they
fell into that gray area where selling one was in some violation of FCC
rules and regs for 3rd party interception of a private (or intended private)
broadcast.
 
The thing is, once the internet and access to it became the norm (early
2000's), I really don't think those rebroadcasters could survive. On nearly
any platform or device there is usually one or two applications available
for listening to radio stations from aroound the world, if not dozens of
websites that retransmit them.
 
I'd guess there are plenty of 80+ year old grandmothers from the old country
who can work turning on and off a radio rather than firing up a laptop but I
doubt there is enough to make any money off them.
 
-bruce
bje@ripco.com
jurb6006@gmail.com: May 28 02:07PM -0700

Now dammit, I know how a ramp generator works and I know how a relaxation oscillator works, which is what the ramp generator sometimes becomes in a scope. I wish Jim Yanik was around.
 
I got two. One is a Tek 465B that works but B sweep does not. the waveform that the plates indicates that when switched it IS switching to B sweep but not starting.
 
The other is a 204, and the main sweep seems to have the same problem. the final amps are fine in both units.
 
The problem I have with these is actually following the schematics. Seriously, I think if I could print them out on HUGE paper I might be able to follow it. But that is not practical at this time nor is it practical with these schematics the way they are split up.
 
I hae already got TWO copies of the PDFs so I can have two instances open, because with the new and improved Acrobat Reader it won't open the same copy twice and I haven't been able to find a way to open two pages at the same time in one instance. Having to go from page 250 to page 146 is a bunch of bullshit.
 
But anyway, we got two scopes, kinda similar in design, with the same problem. What is the common problem when the sweep doesn't start ?
 
I understand the principles of operation, it is just that I can't run their gauntlet. From the time base part go to this board for the triggering, and then this board for the switching of the triggering and then way the out in bumfuckt Egypt somewhere to trace the signal.
 
It is just so much of a bitch to follow.
 
The Hameg is a 204. It works fine in XY mode. There is a slight DC shift when you change the time/div setting, pretty much at the lower ranges.
 
The Tek is a 465B and actually woks but B sweep does not. It IS switching to B sweep but B sweep never starts no matter what you do. On page 267 of the service manual, Q6036 has the same voltage on all three terminals but does no check shorted. That makes it somewhat suspect but doubtful it causes this problem. I supplies a calibrated voltage to the ramp generator. Generally if you give it a little more voltage you get more ramp. This gets no ramp, just sits there. In fact if the circuit is entirely open somewhere that is pretty much what would happen.
 
Maybe I should rethink this Q6036.
 
Any pointers welcome on either scope. I know they ain't the cat's ass but I would like to see them work.
"tom" <tmiller11147@verizon.net>: May 28 05:54PM -0400

<jurb6006@gmail.com> wrote in message
news:8168144b-e201-4fec-bdd5-158f8a0c0a2f@googlegroups.com...
Now dammit, I know how a ramp generator works and I know how a relaxation
oscillator works, which is what the ramp generator sometimes becomes in a
scope. I wish Jim Yanik was around.
 
I got two. One is a Tek 465B that works but B sweep does not. the waveform
that the plates indicates that when switched it IS switching to B sweep but
not starting.
 
The other is a 204, and the main sweep seems to have the same problem. the
final amps are fine in both units.
 
The problem I have with these is actually following the schematics.
Seriously, I think if I could print them out on HUGE paper I might be able
to follow it. But that is not practical at this time nor is it practical
with these schematics the way they are split up.
 
I hae already got TWO copies of the PDFs so I can have two instances open,
because with the new and improved Acrobat Reader it won't open the same copy
twice and I haven't been able to find a way to open two pages at the same
time in one instance. Having to go from page 250 to page 146 is a bunch of
bullshit.
 
But anyway, we got two scopes, kinda similar in design, with the same
problem. What is the common problem when the sweep doesn't start ?
 
I understand the principles of operation, it is just that I can't run their
gauntlet. From the time base part go to this board for the triggering, and
then this board for the switching of the triggering and then way the out in
bumfuckt Egypt somewhere to trace the signal.
 
It is just so much of a bitch to follow.
 
The Hameg is a 204. It works fine in XY mode. There is a slight DC shift
when you change the time/div setting, pretty much at the lower ranges.
 
The Tek is a 465B and actually woks but B sweep does not. It IS switching to
B sweep but B sweep never starts no matter what you do. On page 267 of the
service manual, Q6036 has the same voltage on all three terminals but does
no check shorted. That makes it somewhat suspect but doubtful it causes this
problem. I supplies a calibrated voltage to the ramp generator. Generally if
you give it a little more voltage you get more ramp. This gets no ramp, just
sits there. In fact if the circuit is entirely open somewhere that is pretty
much what would happen.
 
Maybe I should rethink this Q6036.
 
Any pointers welcome on either scope. I know they ain't the cat's ass but I
would like to see them work.
 
 
+++++++++++++++++++++++++++++++++++++++++=
 
 
Do you have waveform 73 on schematic 8? That is the B start gate. Start
there.
Trevor Wilson <trevor@SPAMBLOCKrageaudio.com.au>: May 29 08:46AM +1000


> Maybe I should rethink this Q6036.
 
> Any pointers welcome on either scope. I know they ain't the cat's ass
> but I would like to see them work.
 
**The 465B is a great old 'scope, BUT, like many Tektronix 'scopes of
the time, tunnel diodes are used in the sweep systems. The tunnel diodes
used are VERY hard to source.
 
 
 
--
Trevor Wilson
www.rageaudio.com.au
 
---
This email has been checked for viruses by Avast antivirus software.
https://www.avast.com/antivirus
N_Cook <diverse@tcp.co.uk>: May 29 10:33AM +0100


> The Tek is a 465B and actually woks but B sweep does not. It IS switching to B sweep but B sweep never starts no matter what you do. On page 267 of the service manual, Q6036 has the same voltage on all three terminals but does no check shorted. That makes it somewhat suspect but doubtful it causes this problem. I supplies a calibrated voltage to the ramp generator. Generally if you give it a little more voltage you get more ramp. This gets no ramp, just sits there. In fact if the circuit is entirely open somewhere that is pretty much what would happen.
 
> Maybe I should rethink this Q6036.
 
> Any pointers welcome on either scope. I know they ain't the cat's ass but I would like to see them work.
 
With any old-school-scope repair, it is sensible to check out all switch
and header contacts for corrossion problems, before getting bogged down
in circuit minutei.
The "well it was working fine, before I left it on the shelf for a year"
scenario.
N_Cook <diverse@tcp.co.uk>: May 29 09:07AM +0100

On 27/05/2016 23:11, Jon Elson wrote:
> just look like a printer or something?
 
> Thanks,
 
> Jon
 
She was transferring data composed on her ordinary tablet, via wifi, to
the cutter. She said the company's interface s/w is freely available to
download off their www and use your own typefaces and so I presume other
graphical input, but needs checking on that.
I should say she was the UK rep for these things and had been using them
personally for at least a year, so not a numpty
Download their s/w and try it.
She was happy to try thin copper foil as she had cut aluminium IIRC
kitchen foil previously. But 2oz copper, unknown, as also full cut of
3mm is possible,eg the leather samples I don't know about selective
shallow depth of cut over 2or 3mm .
With my slug foil, it came on siliconised? backing tape for easy peel,
feeding as is with backing to the cutter, it tore off the backing.
Unpeeling the foil, with its gummy backing intact, and sticking to the
usual feed-in sheet, worked fine, selecting "vinyl" cut depth option.
Limited to 1 x 2 foot area of cutting, total sheet area
So for the "dress-maker" in this thread, find bare foil, coat with
something to strongish bond to some flexible heat tolerant sheet and
feed into the cutter, and needle off surplus material
Danny DiAmico <dannydiamico@yahoo.com>: May 29 02:10AM

On Thu, 26 May 2016 10:15:34 -0700, Oren wrote:
 
> Maybe I could give a lesson on 'women folk on my case'. No Honey Do
> List, it's a "dead line list". I made it through Tuesday (LMAO).
 
Hi Oren,
 
The good news is that the rebuilt Whirlpool motor control board from
circuit board medics worked fine.
 
So all that matters now is the lesson learned for others.
 
Total cost was $165 + about $20 (I forget exactly how much shipping was)
and the turnaround time was atrocious but that's partly my fault since I
was unsure of how to proceed. Normal turnaround time should be four to
five days to get there, a day or two to test & rebuild, and then four or
five days to get back (it was from California to North Carolina and I
didn't pay the $40 for two-day shipping by Fedex).
 
A brand new board at a local appliance store would be $191 + about 10% tax
with a turnaround time of 1 day (let's double that, to two days or three
days to be safe).
 
Seems like a no brainer, in hindsight. The one thing is that the circuit
board medics did test the computer control board in addition to the motor
control board, so, in essence, we have to factor in that costs somewhere.
 
The DIAGNOSTIC lesson learned is pretty simple, but it's only something
that is learned from experience (which the circuit board medics did have).
 
If a Whirlpool duet Sport has an F28 (or F11 on Kenmore models), then
almost certainly it's the Motor Control Board, so, the FIRST THING you
should do for diagnostics is simply remove the back washer plate, remove
the lower brace, and remove the motor control board.
 
You *will* break every one of the four of five cheap plastic tie-wrap
butterfly anchors. I simply duct taped the new wires back in place but a
more elegant solution would have been to purchase a few of those anchor
clips.
 
Once you remove the motor control board, you will see black spots, which
is your confirmation of failure.
 
In the end, that is the simplest advice for an F28 (or F11) communications
error. The advice only works because the circuit board medics said an F28
communications error is 99% of the time the motor control board (or the
blue wires going to it fell off).
Danny DiAmico <dannydiamico@yahoo.com>: May 29 02:20AM

On Thu, 26 May 2016 16:02:12 -0400, Tekkie® wrote:
 
 
> I would not wash the new board. Place it where the old board was. I
> would collect $5 for every complaint. If they don't like that then tell
> them to go to the stream with their rocks.
 
I put the board in the washing machine, and it worked.
Here is the summary for the next person.
 
1. A power outage can fry your washing machine.
2. If you get a Whirlpool F28 communications error (same as Kenmore F11
I'm told), then 99% of the time is is a fried Motor Control Board (I'm
told).
3. Remove the back plate of the washing machine & the lower brace to
expose the motor control board
4. Remove the upper cover of the washing machine to expose the main
computer board.
5. Look around. Blue wires are critical. So check the blue wires from the
CCU to the MCU. Otherwise, remove the motor control board and check for
burn marks.
 
If you see evidence of damage on the motor control board, just go buy a
new one for around $200 at a local appliance store. (Whirlpool factory
prices area about $320 and Ebay is as low as $50 but you have to be
confident of the supplier).
vjp2.at@at.BioStrategist.dot.dot.com: May 28 09:33PM

I think the reason my (spring wound) bath fan timer switch sticks is when I
reset it, ie, change it form say 20 min to 40 min. It is spring wound. I know
folks who have such switches for twenty years, and they blame me for my
problems. I have a replacement, and I changed it before every three years,
but am curious if it's my fault to figure it out. Also, may have to extend
the wires using scotchlock, so reluctant.
 
- = -
Vasos Panagiotopoulos, Columbia'81+, Reagan, Mozart, Pindus, BioStrategist
http://www.panix.com/~vjp2/vasos.htm
---{Nothing herein constitutes advice. Everything fully disclaimed.}---
[Homeland Security means private firearms not lazy obstructive guards]
[Urb sprawl confounds terror] [Phooey on GUI: Windows for subprime Bimbos]
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