sci.electronics.repair@googlegroups.com

Today's topics:

* Followup re: USB malfunction ? / Ezbus digital mixer /Ez-usb USB chip - 2
messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/a3a382fddd16c1f3?hl=en
* The Bob Parker Anatek Blue ESR Meter - 2 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/bba8d6130db676c0?hl=en
* Today's Lead Free Crap Solder Stories ... - 14 messages, 10 authors
http://groups.google.com/group/sci.electronics.repair/t/161210aa2275c858?hl=en
* technics amp SU-Z200 low volume problem - 2 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/9e0b05e00f883d65?hl=en
* LCD Desktop Monitor Fading to White, then Black - 3 messages, 2 authors
http://groups.google.com/group/sci.electronics.repair/t/2c04885c7b46754a?hl=en
* Model Sony KDS 60-A2000 no vertical - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/b1314e439e2f7a44?hl=en
* Bauer 16 mm projector schematic - 1 messages, 1 author
http://groups.google.com/group/sci.electronics.repair/t/a1d099030dd48ec6?hl=en

==============================================================================
TOPIC: Followup re: USB malfunction ? / Ezbus digital mixer /Ez-usb USB chip
http://groups.google.com/group/sci.electronics.repair/t/a3a382fddd16c1f3?hl=en
==============================================================================

== 1 of 2 ==
Date: Fri, May 21 2010 12:21 am
From: "N_Cook"

I'm thinking out in wwwland must be some general Cypress utility for
transfering minimal data into their chippery to redesignate VID/PID
pipe/endpoints etc.
Put a switch in the SDA line , leave open at power up , so USB designated
Cypress, then after 3 seconds when clock line is high close the switch. Then
upload something to the memory, enough to redisignate the USB identity. Then
power down and power up and transfer the mixer firmware.

== 2 of 2 ==
Date: Fri, May 21 2010 3:23 am
From: "N_Cook"

Anyone familiar with this sort of utility
EZ Loader Custom USB Firmware Loader Driver
http://www.cypress.com/?docID=4503
just to rejig USB ident to then use the firmware transfer for the particular
application ? here a digital mixer that is otherwise dead from corrupted
firmware transfer.

eg p4
" 8. Before you can use your new firmware driver you will need
to bind it with your device. This is done by loading the
serial EEPROM with the VID/PID combination defined in
the INF file you create for your custom USB device. This
is the first of two VID/PID combinations your device will
use. When the VID/PID in the EEPROM is reported to the
host, the host will invoke the wdgtldr.sys which loads your
firmware. To load your VID/PID combination in the serial
EEPROM open the EZ-USB Control Panel, ensure the
Target Field matches your target device, and download
the Vend_ax.hex example. "

==============================================================================
TOPIC: The Bob Parker Anatek Blue ESR Meter
http://groups.google.com/group/sci.electronics.repair/t/bba8d6130db676c0?hl=en
==============================================================================

== 1 of 2 ==
Date: Fri, May 21 2010 1:59 am
From: "Arfa Daily"

"Wild_Bill" <wb_wildbill@XSPAMyahoo.com> wrote in message
news:9%mJn.99527$vX7.15348@en-nntp-11.dc1.easynews.com...
>I bought a new Blue ESR meter kit from Anatek recently. The kit was
>received very quickly, and assembly was easy. The kit is neatly packed, the
>circuit board is high quality and clearly marked for correct component
>placement.
>
> Anatek created an online forum for discussion of their products, so, if
> someone encounters problems after assembly of the kit, they can find
> several solutions and/or get quick help
> http://www.anatekcorp.com/forum/viewforum.php?f=3
>
> Aside from proper component placement, improper soldering technique would
> probably be the only issue that an inexperienced kit builder or DIY-type
> would experience.
> If one is not trying to rush thru the assembly, there aren't likely be any
> problems at completion.
>
> I've intended to get one of the Bob Parker ESR models for many years, but
> I procrastinate. I heard of the Procrastinators of America about 40 years
> ago but never got around to joining.
>
> I had read possibly hundreds of positive comments about Bob's ESR meters
> over the years, and new users continue to praise them.
>
> I've used Sencore Z-Meters for lots of years, and the Sencore models are
> reliable, and also offer many capacitor and inductor test-analyze
> features/functions beyond ESR testing, but the Bob Parker ESR meter is
> much more convenient to use for quickly checking caps on a board.
> Before the Sencore units, I relied on a digital capacitance meter and a
> leakage tester built from a magazine article in the 80s, scope and DMM.
>
> The Sencore units are very sensitive to any resistance of the connections
> for the test cable.. oxidation at the front panel BNC connector can
> prevent the circuits from zeroing properly (fault condition).
> The Sencore test cable is about a 3' length of RG-62 B/U which isn't as
> easily handled as the simple test leads of the Blue ESR meter.
> The Blue ESR Meter is agreeable to to simple test leads and different
> attachments such as alligator clips or test probes.
>
> Like many others who like to or need to investigate circuit faults, I'm
> also delighted with the Blue ESR Meter.
>
> --
> Cheers,
> WB
> .............
>

I've used an original Bob Parker designed Dick Smith kit on a daily basis
for years, and have always found it a pleasure to use. When the "Blue" was
released by Anatek from Bob's design revisions, I built a kit and wrote a
review for an electronics trade magazine here in the UK. I too found it easy
to build, and I agree with you that any reasonably experienced electronics
enthusiast who can handle a soldering iron, would be able to build the kit
with a 99% chance of 'first time' success. As you have found, a fine
instrument to own and use, and a worthy successor to Bob's original design.

And no, I'm not connected to Bob (except as a friend on the 'net for some
years) or to John at Anatek, in any way !

Arfa

== 2 of 2 ==
Date: Fri, May 21 2010 7:08 am
From: Jim Yanik

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in
news:1YrJn.51963$ER.7882@newsfe07.ams2:

>
> "Wild_Bill" <wb_wildbill@XSPAMyahoo.com> wrote in message
> news:9%mJn.99527$vX7.15348@en-nntp-11.dc1.easynews.com...
>>I bought a new Blue ESR meter kit from Anatek recently. The kit was
>>received very quickly, and assembly was easy. The kit is neatly
>>packed, the circuit board is high quality and clearly marked for
>>correct component placement.
>>
>> Anatek created an online forum for discussion of their products, so,
>> if someone encounters problems after assembly of the kit, they can
>> find several solutions and/or get quick help
>> http://www.anatekcorp.com/forum/viewforum.php?f=3
>>
>> Aside from proper component placement, improper soldering technique
>> would probably be the only issue that an inexperienced kit builder or
>> DIY-type would experience.
>> If one is not trying to rush thru the assembly, there aren't likely
>> be any problems at completion.
>>
>> I've intended to get one of the Bob Parker ESR models for many years,
>> but I procrastinate. I heard of the Procrastinators of America about
>> 40 years ago but never got around to joining.
>>
>> I had read possibly hundreds of positive comments about Bob's ESR
>> meters over the years, and new users continue to praise them.
>>
>> I've used Sencore Z-Meters for lots of years, and the Sencore models
>> are reliable, and also offer many capacitor and inductor test-analyze
>> features/functions beyond ESR testing, but the Bob Parker ESR meter
>> is much more convenient to use for quickly checking caps on a board.
>> Before the Sencore units, I relied on a digital capacitance meter and
>> a leakage tester built from a magazine article in the 80s, scope and
>> DMM.
>>
>> The Sencore units are very sensitive to any resistance of the
>> connections for the test cable.. oxidation at the front panel BNC
>> connector can prevent the circuits from zeroing properly (fault
>> condition). The Sencore test cable is about a 3' length of RG-62 B/U
>> which isn't as easily handled as the simple test leads of the Blue
>> ESR meter. The Blue ESR Meter is agreeable to to simple test leads
>> and different attachments such as alligator clips or test probes.
>>
>> Like many others who like to or need to investigate circuit faults,
>> I'm also delighted with the Blue ESR Meter.
>>
>> --
>> Cheers,
>> WB
>> .............
>>
>
> I've used an original Bob Parker designed Dick Smith kit on a daily
> basis for years, and have always found it a pleasure to use. When the
> "Blue" was released by Anatek from Bob's design revisions, I built a
> kit and wrote a review for an electronics trade magazine here in the
> UK. I too found it easy to build, and I agree with you that any
> reasonably experienced electronics enthusiast who can handle a
> soldering iron, would be able to build the kit with a 99% chance of
> 'first time' success. As you have found, a fine instrument to own and
> use, and a worthy successor to Bob's original design.
>
> And no, I'm not connected to Bob (except as a friend on the 'net for
> some years) or to John at Anatek, in any way !
>
> Arfa
>
>
>

I have yet to read about anyone who disliked the Bob Parker ESR meter.
I love mine.

KUDOS to him!

--
Jim Yanik
jyanik
at
localnet
dot com

==============================================================================
TOPIC: Today's Lead Free Crap Solder Stories ...
http://groups.google.com/group/sci.electronics.repair/t/161210aa2275c858?hl=en
==============================================================================

== 1 of 14 ==
Date: Fri, May 21 2010 2:06 am
From: "Arfa Daily"

"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ht5c0o$2m0$1@news.eternal-september.org...
> Arfa Daily <arfa.daily@ntlworld.com> wrote in message
> news:mdlJn.18479$ea4.8777@newsfe29.ams2...
>> The first is the Warrior amp that I posted on here about, looking for
>> schematics. None were found, and as expected, the importer ignored my
> pleas,
>> so I decided I would spend a half hour on it 'blind'.
>>
>> It turned out to not be too difficult to get the main PCB out, complete
> with
>> heatsinks and back panel. The wiring was long enough to allow the board
>> to
>> be turned over, without having to disconnect everything. The fault was
> that
>> one of the two identical output stages was behaving as a pretty good half
>> wave rectifier, but only with a load connected. With no load, an applied
>> sine wave was perfectly symmetrical at the output terminals, and of
> similar
>> size to the good channel. With a load connected, the negative excursions
>> disappeared almost totally. Nothing was burning, and the the output
> protect
>> didn't even fire until the wick was turned well up, which led me to
> believe
>> that the problem may well be back in the driver stages or earlier. As
> there
>> are two identical amps, I figured that I would start with a few
> comparitive
>> resistance checks between channels. Quickly, I found that at the base pin
> of
>> one of the driver transistors, I had a reading of 3k or so on the good
>> channel, but open circuit at the same point on the bad channel. I
>> followed
>> the print back and took another reading and Lo! - 3k ...
>>
>> So I went back to the transistor leg - open, but at the joint, 3k. I tell
>> you, I examined that joint with the strongest light and magnifier that I
>> have, but you could not see a problem with it. However, as soon as it was
>> resoldered, 3k on the leg as well, and the amp then worked normally. This
> is
>> the problem with lead free. You can no longer spot bad joints by eye, and
>> they don't behave like conventional bad joints any more.
>>
>> The second one was a Vox combo. This one was reported as "goes off after
>> a
>> while - tap top to get it back". It actually ran for about 2 hours,
>> during
>> which time I thrashed the output stage so hard you couldn't touch the
>> heatsink, and periodically knocked seven bells out of it with the butt
>> end
>> of a large philips screwdy. At no time did it show any signs of
>> intermittency. I was actually on the phone to the store that it came to
>> me
>> from, to check if they knew the owner, and whether he was savvy, or a
>> numpty, when it went off. Just like that. No provocation. You could then
>> lightly tap the top of the chassis just about anywhere, and it would come
>> and go at will. So easy was it to make it do it, you would have thought
> that
>> the joint causing it would have been really easily spotted. I twisted and
>> wiggled everything I could, but nothing made it do it, but still the
>> lightest tap, and there it went.
>>
>> Eventually, after a frustrating session of blanket resoldering that did
> no
>> good at all, I came to a power resistor standing up off the board. It was
> a
>> component that I had previously twisted. This time I pulled it, and one
> leg
>> just came right out of the board. The joint looked perfectly normal - for
>> lead-free that is - but it had not whetted the resistor leg at all. How
> the
>> hell could that take two hours to go bad, not be responsive at all before
>> that time, and then when it has gone bad, not respond to twisting, but be
> so
>> tap sensitive that you could make it come and go with a feather? I HATE
>> lead-free with a passion.
>>
>> If it ever finds its way into avionics, be afraid, be VERY afraid ...
>>
>> Arfa
>>
>>
>
>
> I'm thinking of making a tug-test tool for PbF checking. Probably based on
> an automatic centre punch tool latch mechanism but somehow inverted in
> operation. How many ounces or grams of pullout tension do you think a 1/3
> W
> resistor lead/wire link/TO92 wire should resist pulling out , leaded
> solder
> that is.
>
>
> --
> Diverse Devices, Southampton, England
> electronic hints and repair briefs , schematics/manuals list on
> http://diverse.4mg.com/index.htm
>
>

I would have thought pretty much to the wire breaking point. How many times
have you hooked a screwdriver or whatever, under a component in order to
unsolder one end, then heated the joint on the other side of the board,
whilst applying pressure to the link / component, only to then have it snap
on you, because you were heating the joint next to the one you were supposed
to be ... :-)

Arfa

== 2 of 14 ==
Date: Fri, May 21 2010 3:04 am
From: "N_Cook"

Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:I2sJn.51965$ER.41189@newsfe07.ams2...
>
> "N_Cook" <diverse@tcp.co.uk> wrote in message
> news:ht5c0o$2m0$1@news.eternal-september.org...
> > Arfa Daily <arfa.daily@ntlworld.com> wrote in message
> > news:mdlJn.18479$ea4.8777@newsfe29.ams2...
> >
> I would have thought pretty much to the wire breaking point. How many
times
> have you hooked a screwdriver or whatever, under a component in order to
> unsolder one end, then heated the joint on the other side of the board,
> whilst applying pressure to the link / component, only to then have it
snap
> on you, because you were heating the joint next to the one you were
supposed
> to be ... :-)
>
> Arfa
>
>

One problem is ,for likes of TO92 and standardised tug , the use of surgical
artery forceps to grip before pulling, too much grip force and you squash
the lead.
I just tried with a board and counter weights on kitchen scales and I would
say I use about 1Kg of tug with thin nose pliers, pulling perpendicular to
the pcb.

What date was the VOX ? I've previously found 2 ,tug test failing, loose
links due to PbF on a 2005 Vox AC30 , AC30CC2X . Found in passing as
otherwise in for valve and intrusive tremolo initiated rumble

--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://diverse.4mg.com/index.htm

>

== 3 of 14 ==
Date: Fri, May 21 2010 3:50 am
From: "Colin Horsley"

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in message
news:I2sJn.51965$ER.41189@newsfe07.ams2...

I would have thought pretty much to the wire breaking point. How many times
have you hooked a screwdriver or whatever, under a component in order to
unsolder one end, then heated the joint on the other side of the board,
whilst applying pressure to the link / component, only to then have it snap
on you, because you were heating the joint next to the one you were supposed
to be ... :-)

Arfa

______________________

yep, done that!

Colin

== 4 of 14 ==
Date: Fri, May 21 2010 5:28 am
From: Meat Plow

On Fri, 21 May 2010 02:20:17 +0100, Arfa Daily wrote:

> The first is the Warrior amp that I posted on here about, looking for
> schematics. None were found, and as expected, the importer ignored my
> pleas, so I decided I would spend a half hour on it 'blind'.
>
> It turned out to not be too difficult to get the main PCB out, complete
> with heatsinks and back panel. The wiring was long enough to allow the
> board to be turned over, without having to disconnect everything. The
> fault was that one of the two identical output stages was behaving as a
> pretty good half wave rectifier, but only with a load connected. With no
> load, an applied sine wave was perfectly symmetrical at the output
> terminals, and of similar size to the good channel. With a load
> connected, the negative excursions disappeared almost totally. Nothing
> was burning, and the the output protect didn't even fire until the wick
> was turned well up, which led me to believe that the problem may well be
> back in the driver stages or earlier. As there are two identical amps, I
> figured that I would start with a few comparitive resistance checks
> between channels. Quickly, I found that at the base pin of one of the
> driver transistors, I had a reading of 3k or so on the good channel, but
> open circuit at the same point on the bad channel. I followed the print
> back and took another reading and Lo! - 3k ...
>
> So I went back to the transistor leg - open, but at the joint, 3k. I
> tell you, I examined that joint with the strongest light and magnifier
> that I have, but you could not see a problem with it. However, as soon
> as it was resoldered, 3k on the leg as well, and the amp then worked
> normally. This is the problem with lead free. You can no longer spot bad
> joints by eye, and they don't behave like conventional bad joints any
> more.
>
> The second one was a Vox combo. This one was reported as "goes off after
> a while - tap top to get it back". It actually ran for about 2 hours,
> during which time I thrashed the output stage so hard you couldn't touch
> the heatsink, and periodically knocked seven bells out of it with the
> butt end of a large philips screwdy. At no time did it show any signs of
> intermittency. I was actually on the phone to the store that it came to
> me from, to check if they knew the owner, and whether he was savvy, or a
> numpty, when it went off. Just like that. No provocation. You could then
> lightly tap the top of the chassis just about anywhere, and it would
> come and go at will. So easy was it to make it do it, you would have
> thought that the joint causing it would have been really easily spotted.
> I twisted and wiggled everything I could, but nothing made it do it, but
> still the lightest tap, and there it went.
>
> Eventually, after a frustrating session of blanket resoldering that did
> no
> good at all, I came to a power resistor standing up off the board. It
> was a component that I had previously twisted. This time I pulled it,
> and one leg just came right out of the board. The joint looked perfectly
> normal - for lead-free that is - but it had not whetted the resistor leg
> at all. How the hell could that take two hours to go bad, not be
> responsive at all before that time, and then when it has gone bad, not
> respond to twisting, but be so tap sensitive that you could make it come
> and go with a feather? I HATE lead-free with a passion.
>
> If it ever finds its way into avionics, be afraid, be VERY afraid ...
>
> Arfa

:)

== 5 of 14 ==
Date: Fri, May 21 2010 6:03 am
From: Ron

On 21/05/2010 13:28, Meat Plow wrote:
> On Fri, 21 May 2010 02:20:17 +0100, Arfa Daily wrote:

>>
>> If it ever finds its way into avionics, be afraid, be VERY afraid ...
>>
>> Arfa
>
> :)

Come to think of it, lead free solder and volcanic ash look very similar.

Ron

== 6 of 14 ==
Date: Fri, May 21 2010 6:21 am
From: "William Sommerwerck"

> If it ever finds its way into avionics, be afraid, be VERY afraid...

Shouldn't be a problem. How often are F-15s dumped in landfills?

== 7 of 14 ==
Date: Fri, May 21 2010 7:00 am
From: "William R. Walsh"

Hi!

> Shouldn't be a problem. How often are F-15s dumped in landfills?

Well, if lead free solder causes failures, and as a result one
crashes...what's to stop the site from being a landfill?

William

== 8 of 14 ==
Date: Fri, May 21 2010 7:01 am
From: Jim Yanik

"Arfa Daily" <arfa.daily@ntlworld.com> wrote in
news:mdlJn.18479$ea4.8777@newsfe29.ams2:

> The first is the Warrior amp that I posted on here about, looking for
> schematics. None were found, and as expected, the importer ignored my
> pleas, so I decided I would spend a half hour on it 'blind'.
>
> It turned out to not be too difficult to get the main PCB out,
> complete with heatsinks and back panel. The wiring was long enough to
> allow the board to be turned over, without having to disconnect
> everything. The fault was that one of the two identical output stages
> was behaving as a pretty good half wave rectifier, but only with a
> load connected. With no load, an applied sine wave was perfectly
> symmetrical at the output terminals, and of similar size to the good
> channel. With a load connected, the negative excursions disappeared
> almost totally. Nothing was burning, and the the output protect didn't
> even fire until the wick was turned well up, which led me to believe
> that the problem may well be back in the driver stages or earlier. As
> there are two identical amps, I figured that I would start with a few
> comparitive resistance checks between channels. Quickly, I found that
> at the base pin of one of the driver transistors, I had a reading of
> 3k or so on the good channel, but open circuit at the same point on
> the bad channel. I followed the print back and took another reading
> and Lo! - 3k ...
>
> So I went back to the transistor leg - open, but at the joint, 3k. I
> tell you, I examined that joint with the strongest light and magnifier
> that I have, but you could not see a problem with it. However, as soon
> as it was resoldered, 3k on the leg as well, and the amp then worked
> normally. This is the problem with lead free. You can no longer spot
> bad joints by eye, and they don't behave like conventional bad joints
> any more.
>
> The second one was a Vox combo. This one was reported as "goes off
> after a while - tap top to get it back". It actually ran for about 2
> hours, during which time I thrashed the output stage so hard you
> couldn't touch the heatsink, and periodically knocked seven bells out
> of it with the butt end of a large philips screwdy. At no time did it
> show any signs of intermittency. I was actually on the phone to the
> store that it came to me from, to check if they knew the owner, and
> whether he was savvy, or a numpty, when it went off. Just like that.
> No provocation. You could then lightly tap the top of the chassis just
> about anywhere, and it would come and go at will. So easy was it to
> make it do it, you would have thought that the joint causing it would
> have been really easily spotted. I twisted and wiggled everything I
> could, but nothing made it do it, but still the lightest tap, and
> there it went.
>
> Eventually, after a frustrating session of blanket resoldering that
> did no
> good at all, I came to a power resistor standing up off the board. It
> was a component that I had previously twisted. This time I pulled it,
> and one leg just came right out of the board. The joint looked
> perfectly normal - for lead-free that is - but it had not whetted the
> resistor leg at all. How the hell could that take two hours to go bad,
> not be responsive at all before that time, and then when it has gone
> bad, not respond to twisting, but be so tap sensitive that you could
> make it come and go with a feather? I HATE lead-free with a passion.
>
> If it ever finds its way into avionics, be afraid, be VERY afraid ...
>
> Arfa
>
>
>

most of the time,when you have an intermittent,if you tap it,you end up
working the joint to a better connection and you don't see the
intermittent.
you have to leave it alone and wait patiently for the IM to show up,then
lightly tap around to find the area most sensitive.

--
Jim Yanik
jyanik
at
localnet
dot com

== 9 of 14 ==
Date: Fri, May 21 2010 7:06 am
From: Jim Yanik

"William Sommerwerck" <grizzledgeezer@comcast.net> wrote in
news:ht61dl$i4s$1@news.eternal-september.org:

>> If it ever finds its way into avionics, be afraid, be VERY afraid...
>
> Shouldn't be a problem. How often are F-15s dumped in landfills?
>
>
>

there's a guy who bought a scrapped,"demilled" T-38,with a cracked
airframe,he owned a aircraft maintenance shop and was able to restore it to
flight condition,and he has the only civilian,flyable T-38 jet.
It's the trainer version of the F-5 fighter,the "Mig 28" in Top Gun.

--
Jim Yanik
jyanik
at
localnet
dot com

== 10 of 14 ==
Date: Fri, May 21 2010 8:51 am
From: Jeffrey D Angus

Wild_Bill wrote:
> What's taken place, I think, which I suspect was intentionally
> forced upon most of us, is that manufacturers wanted to lower
> everyone's expectations of quality.

I've been watching this "trend" since the '70s.

My opinion is that we as consumers have brought this on
ourselves with the attitude of: "I don't care if it's
crap, I want it now, I want it cheap and I'll be bored
with it within a year anyway."

Although this isn't entirely new. You could be cheap or
shoddy merchandise for as long as they've been bartering
from stuff. It's just that the ability to mass produce
garbage has exceeded our wildest expectations.

Jeff

--
"Egotism is the anesthetic that dulls the pain of stupidity."
Frank Leahy, Head coach, Notre Dame 1941-1954

http://www.stay-connect.com

== 11 of 14 ==
Date: Fri, May 21 2010 9:04 am
From: "William Sommerwerck"

>> What's taken place, I think, which I suspect was intentionally
>> forced upon most of us, is that manufacturers wanted to lower
>> everyone's expectations of quality.

> I've been watching this "trend" since the '70s.

> My opinion is that we as consumers have brought this on
> ourselves with the attitude of: "I don't care if it's
> crap, I want it now, I want it cheap and I'll be bored
> with it within a year anyway."

> Although this isn't entirely new. You could be cheap or
> shoddy merchandise for as long as they've been bartering
> from stuff. It's just that the ability to mass produce
> garbage has exceeded our wildest expectations.

I think that's only half the truth. I was born in 1947, and the rate of
technological change is at least five to ten times what it was 50 years ago.
ICs and SMTs, inserted by robots, make possible the "cheap" electronics that
can be easily discarded to make room for the next quarter's spasm of
improvements.

== 12 of 14 ==
Date: Fri, May 21 2010 9:23 am
From: "Arfa Daily"

"N_Cook" <diverse@tcp.co.uk> wrote in message
news:ht5los$50l$1@news.eternal-september.org...
> Arfa Daily <arfa.daily@ntlworld.com> wrote in message
> news:I2sJn.51965$ER.41189@newsfe07.ams2...
>>
>> "N_Cook" <diverse@tcp.co.uk> wrote in message
>> news:ht5c0o$2m0$1@news.eternal-september.org...
>> > Arfa Daily <arfa.daily@ntlworld.com> wrote in message
>> > news:mdlJn.18479$ea4.8777@newsfe29.ams2...
>> >
>> I would have thought pretty much to the wire breaking point. How many
> times
>> have you hooked a screwdriver or whatever, under a component in order to
>> unsolder one end, then heated the joint on the other side of the board,
>> whilst applying pressure to the link / component, only to then have it
> snap
>> on you, because you were heating the joint next to the one you were
> supposed
>> to be ... :-)
>>
>> Arfa
>>
>>
>
> One problem is ,for likes of TO92 and standardised tug , the use of
> surgical
> artery forceps to grip before pulling, too much grip force and you squash
> the lead.
> I just tried with a board and counter weights on kitchen scales and I
> would
> say I use about 1Kg of tug with thin nose pliers, pulling perpendicular to
> the pcb.
>
> What date was the VOX ? I've previously found 2 ,tug test failing, loose
> links due to PbF on a 2005 Vox AC30 , AC30CC2X . Found in passing as
> otherwise in for valve and intrusive tremolo initiated rumble
>
>
> --
> Diverse Devices, Southampton, England
> electronic hints and repair briefs , schematics/manuals list on
> http://diverse.4mg.com/index.htm
>
>>
>

It was a Vox Valvetronix combo - one of those things with the built in
digital amp simulator that purports to make it sound like an AC30, or an
AC15, or a Tweed or a 70's Brit amp or an 80's Brit amp, or a dustbin full
of marbles or whatever. I didn't take much notice of what year, but the
board was marked with a PbF symbol. It last crossed my bench two years ago
almost to the day, when the owner had me fit a buffered variable level line
out to the back panel, so at least 2008 and probably a bit before that.

Arfa

== 13 of 14 ==
Date: Fri, May 21 2010 9:25 am
From: "Arfa Daily"

"Ron" <ron@lunevalleyaudio.com> wrote in message
news:SpadnQMzyv8qGWvWnZ2dnUVZ8iSdnZ2d@bt.com...
> On 21/05/2010 13:28, Meat Plow wrote:
>> On Fri, 21 May 2010 02:20:17 +0100, Arfa Daily wrote:
>
>>>
>>> If it ever finds its way into avionics, be afraid, be VERY afraid ...
>>>
>>> Arfa
>>
>> :)
>
> Come to think of it, lead free solder and volcanic ash look very similar.
>
> Ron

Cracker, Ron ! LOL !! :-)))

Arfa

== 14 of 14 ==
Date: Fri, May 21 2010 9:33 am
From: Smitty Two

In article <mdlJn.18479$ea4.8777@newsfe29.ams2>,
"Arfa Daily" <arfa.daily@ntlworld.com> wrote:

> I HATE
> lead-free with a passion.

I don't doubt your experiences, and of course this isn't your first rant
about lead-free. I think the early lead-free formulas were inherently
bad, but I think some of the new ones are pretty damn good. I don't mind
working with them at all, and find the "solderability" to be on a par
with lead.

I still use a lot of lead, but some of my customers (who sell to Europe)
specify lead-free. We use Sn96.5Ag3Cu0.5 and have been well-satisfied
with it. I tend to agree with Wild Bill, that manufacturing has been
turned over to the bean-counters, and that the quality issues you're
seeing with consumer products may be due more to shitty practices than
to the abandonment of lead.

==============================================================================
TOPIC: technics amp SU-Z200 low volume problem
http://groups.google.com/group/sci.electronics.repair/t/9e0b05e00f883d65?hl=en
==============================================================================

== 1 of 2 ==
Date: Fri, May 21 2010 3:28 am
From: b

On 20 mayo, 15:40, "William R. Walsh" <wm_wa...@hotmail.com> wrote:
> Hi!
>
> > It's looking as if the IC is shot, and it seesm to be NLA.....
>
> It's a common problem. In a lot of these 80s Technics amplifiers, the
> Sanyo power amplifier IC goes bad. I've come to believe that they are
> somewhat "failure prone". Interestingly enough, it seems that other
> designs using these modules were more reliable--I have some Aiwa "all
> in one" stereo systems and a little Pioneer receiver that use the
> Sanyo module. None of these run as hot as do the Technics
> receivers...perhaps another data point?
>
> Despite being played hard at times, these units have never caused any
> trouble. Of course, most of the time I happened to come across such
> older Technics gear, it had already been treated badly.
>
> There is a more sinister problem--the Sanyo module integrates speaker
> protection through electronic means. The idea is that if one of the
> final transistors breaks, this electronic protection circuit will
> break the path between module and speaker so that your speaker does
> not become exposed to a power supply rail and burn out. Unfortunately,
> the protection circuit is usually destroyed and the speaker burns out.
>
> I thought all of the Technics amplifiers that used these hybrid
> modules relied on the electronic protection. After searching for a
> long time to find a nice one in working condition, I discovered an
> SA-929 receiver (also based on a house numbered Sanyo integrated
> amplifier module) that has an outboard DC protection relay. This
> should save the speakers if anything goes wrong.
>

I think the reason could be the supply voltage. Seems they can take
anything from 27 to 40-odd volts, which might explain the varied
reliability.

I too was surprised at the lack of protection visbile in this amp.
there's only a resistor separating the o/p from the speakers!
ironiocally in this case, the protection seems to kick in far too
early - muting the o/p even when the sound is barely audible.

i just took a look in my spres box and found an STK 4121 II which,
according to a quick look at the dateasheet here :
http://www.datasheetcatalog.org/datasheets2/10/106635_1.pdf
has the same pinout as my 4152 ii

Might this work as a drop in replacement? the output would only be 15
watts, but better than nothing.....
-B

== 2 of 2 ==
Date: Fri, May 21 2010 6:45 am
From: "William R. Walsh"

Hi!

> I think the reason could be the supply voltage. Seems they can
> take anything from 27 to 40-odd volts, which might explain
> the varied reliability.

Hmm...that is a thought. It might also explain why these little
receivers run so darn hot. Interestingly, mine seems to run hottest
when idle.

> I too was surprised at the lack of protection visbile in this amp.
> there's only a resistor separating the o/p from the speakers!
> ironiocally in this case, the protection seems to kick in far too
> early - muting the o/p even when the sound is barely audible.

Be glad it does, but please don't use it with valuable speakers or
depend upon it to work correctly. All too often it...doesn't. The
result is smoke from your speakers.

That is why I was so surprised that the SA-929 receiver I found had an
honest to goodness relay. What motivated Technics to use one there
when they didn't use one in the other models I've seen?

> Might this work as a drop in replacement? the output would only
> be 15 watts, but better than nothing.....

As they're all pin compatible, I think you can pretty much swap them
at will as long as the voltage ranges are the same for each part. You
probably couldn't get away with a bigger module (it would surely
overtax the power supply) but a smaller one ought to work, especially
if not driven hard or into inefficient speakers. The page that I
linked to suggests that sometimes a larger module was used at reduced
voltage and current levels.

You'd be surprised what "just" fifteen watts worth of output power
will do in terms of volume output.

If you try it, please do post back!

William

==============================================================================
TOPIC: LCD Desktop Monitor Fading to White, then Black
http://groups.google.com/group/sci.electronics.repair/t/2c04885c7b46754a?hl=en
==============================================================================

== 1 of 3 ==
Date: Fri, May 21 2010 4:17 am
From: "Dav.p."

So the "working" monitor stopped working today w/ the same symptoms.
------
what do you mean for 'working', them still had power boards swapped?
A monitor can't contaminate anything, it's a stupid thought..
maybe your monitors are produced same day as them has been bopught same day
and caps are equal and fails near same month or week.

== 2 of 3 ==
Date: Fri, May 21 2010 5:48 am
From: saber850

On May 21, 7:17 am, "Dav.p." <davi...@tiscali.it> wrote:
> So the "working" monitor stopped working today w/ the same symptoms.
> ------
> what do you mean for 'working', them still had power boards swapped?
> A monitor can't contaminate anything, it's a stupid thought..
> maybe your monitors are produced same day as them has been bopught same day
> and caps are equal and fails near same month or week.

Before and after I had swapped the power boards, only one of the two
monitors worked--and it contained the same power board each time.

Yes, both monitors were bought at the same time, and used roughly
equally. But one monitor started failing over 18 months ago, while
the other just started this month.

== 3 of 3 ==
Date: Fri, May 21 2010 5:49 am
From: saber850

On May 20, 10:54 pm, saber850 <saber...@yahoo.com> wrote:
> On May 16, 10:42 am, adse...@wheeloyum.com wrote:
>
>
>
> > On May 16, 8:22 am, Mike Tomlinson <m...@jasper.org.uk> wrote:
>
> > > In article <6b0a157b-e045-40eb-a7a9-cee3092a7...@h39g2000yqn.googlegroup
> > > s.com>, saber850 <saber...@yahoo.com> writes
>
> > > >Fortunately, I ordered 2x the caps a couple days ago.  So hopefully
> > > >the problem is in fact the caps and I'll have both fixed soon.
>
> > > It'd be interesting to hear how you got on.
>
> > > --
> > > (\__/)  
> > > (='.'=)  Bunny's thinking about giving Windows 7
> > > (")_(")  a go despite what he's said about it...
>
> > Absolutely!  I intend on posting back with my next steps.
>
> > At this point, I'm still waiting for the parts (currently expected to
> > arrive tomorrow).  I'll say I'm not thrilled to have paid >$8 to ship
> > a 0.4lb package which takes 5 business days to arrive.  Perhaps I'm
> > spoiled by NewEgg's ship time & prices.
>
> > Fortunately, my monitors seem to be playing tag-team on functioning
> > correctly, so I can still function at this point.
>
> I just completed soldering all the new caps to one of the boards!  For
> desoldering, I found it easier to simply heat each lead and gently
> pull the cap out.  The braided copper didn't really help, perhaps
> because the pins are so small.
>
> The good news is that the monitor functions fine (I thought I may have
> messed up one of the caps).  The unfortunate news is that only time
> will tell if the problem is really solved.
>
> I will post back with the status after a couple days.  If all goes
> well, I'll repeat the procedure on the other board.
>
> Thank you all for your help thus far!

Bad news: the monitor w/ the new caps exhibited the same problem when
I first powered it on this morning. Ugh...

==============================================================================
TOPIC: Model Sony KDS 60-A2000 no vertical
http://groups.google.com/group/sci.electronics.repair/t/b1314e439e2f7a44?hl=en
==============================================================================

== 1 of 1 ==
Date: Fri, May 21 2010 5:29 am
From: stokesbr@cox.net

Need your help once again group, and this is my own TV. Got the 4 red
blinks on the power light. Set won't come up. Web search says this
code is loss of verical. I can't find any info other than this. I
hoped that this problem would be somewhat common to this particular
model with a common fix. I don't have the schematic, but will have to
get it if no more info available about this problem. The set is out of
warranty and is only about 3 years old. Anyone aware of this as a
common issue with this set, and the fix? Thanks group.

==============================================================================
TOPIC: Bauer 16 mm projector schematic
http://groups.google.com/group/sci.electronics.repair/t/a1d099030dd48ec6?hl=en
==============================================================================

== 1 of 1 ==
Date: Fri, May 21 2010 9:06 am
From: Smitty Two

Does anyone have, or have suggestions for where to find, a schematic for
a Bauer P8L Universal 16 mm film projector?

TIA ...

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