Toshiba TV29C90 problem; Image fades to black...

"Eeysore"
I'm repairing a Midas Venice mixing console. Try and avoid doing so.
It's a nightmare

Despite the agent's tech insisting that the 'solo' switches are 'self
cleaning', no amount of exercising them will prevent 2 of them behaving
intermittently.

** Obviously YOU lack the necessary Midas touch !!!!!

Maybe just a little WD40 down the shaft will do the trick - not a whole
flood of it mind you.

Don't want that precious console to wind up looking like Venice.....




...... Phil ;-)
 
"Josh9.0" <squalene9er@hotmail.com> wrote in message
news:8b765f73-cf23-4dff-bb78-2712cd42b01d@k30g2000hse.googlegroups.com...
On Sep 7, 11:33 am, "Arfa Daily" <arfa.da...@ntlworld.com> wrote:
"Josh9.0" <squalene...@hotmail.com> wrote in message

news:79d90c8c-939d-46aa-bc3e-352583845566@i76g2000hsf.googlegroups.com...

You need to establish some
facts. So far you have virtually none at all. Go get some and stop
guessing.

OK, How do I do that?
Thanks.

Well, for a start, do as was suggested - and which you seemed to
understand - and check each of the rails for ripple with your 'scope ...

Arfa

Thanks Afra. I checked the rails and they look clean.
The hum has a certain "spike up, down, noise, spike up, down, silence"
pattern.
I'm off to Jaycar now, to buy some tantalums, as it can't hurt, and I
don't like aluminium electros if tantalums are available.

Where can I get a STK025 datasheet ?
I find pages on Google saying such, but when I go there, it's just
datasheets on STK0025 or STK0250.
Even Sanyo's (mfg) site can't help me.
If the rails look clean, and the sound you are hearing has the described
waveshape, then it is more likely that it is a buzz rather than a hum
(subtle difference to the experienced ear) and not a power supply issue at
all. It could be a grounding problem, but really, you need to know where the
offending noise is actually getting in to the amplification chain. With
items such as synths, where there are triangle and square wave generators
running all the time, a simple bad ground can allow all sorts of nasty
ground voltages to start appearing in amplification stages.

Try here for your data sheet

http://www.alldatasheet.com/view.jsp?sSearchword=STK025

Arfa
 
Jim Yanik <jyanik@abuse.gov> wrote in news:Xns9B0F6414993A2jyanikkuanet@
64.209.0.83:

jakdedert <jakdedert@bellsouth.net> wrote in
news:7VJvk.21619$IB6.11347@bignews8.bellsouth.net:

cuhulin@webtv.net wrote:
You shouldn't breath/inhale whatever is inside of those tubes.
cuhulin
........................
Sarah Palin Rocks!
........................

Yeah, vacuum is dangerous to...uh, breathe?

jak


the phosphors are unhealthy to inhale.
The phosphors are very healthy because they don't inhale!

It is unhealthy for US to inhale the phosphors... and breaking the vacuum
can spread phosphors and also the 'getter'.





--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

bz+ser@ch100-5.chem.lsu.edu remove ch100-5 to avoid spam trap
 
"Josh9.0" <squalene9er@hotmail.com> wrote in
news:98da9236-2f66-4b4f-bb2e-b31960bbdc6e@a70g2000hsh.googlegroups.com:

Is there a sci.electronics.organ.repair or similar group?
Might want to try persuing some of the vintage synth sites such as the
following for information etc:

http://www.vintagesynth.com/local/links.shtml
 
"Jamie" = Maynard A. Philbrook, KA1LPA

A radio ham & demented coder scribbler by trade.

Phil Allison:


** Obviously YOU lack the necessary Midas touch !!!!!

Maybe just a little WD40 down the shaft will do the trick - not a whole
flood of it mind you.

Don't want that precious console to wind up looking like Venice.....


..... Phil ;-)


WD-40 (fish oil as main ingredient or used to be) dries out.

** WD40 residue is ordinary light oil - whether it evaporates depends on
ambient temperature and local air flow.

At room temp and with no virtually no air flow, that takes years.


Spraying the contacts for suspected electrical issues, only
temporarily fixes, and normally makes it worse afterwards.

** The idea is to clean the surfaces and flush away contaminants.

Nothing to do with mysterious "electrical issues ".


Since most chemicals tend to deteriorate the contact surfaces
** Light mineral oil is not a corrosive "chemical" - you fool.

and allows for pitted areas that no longer receives regular wiping from
the
switch action, erosion sets in.
** A coating of light oil protects the metal surfaces by excluding moisture
and air - you colossally stupid ASS .

Go away.



....... Phil
 
The OP said he had line-level audio... not a mike.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in the
address)

Life is like a roll of toilet paper; the closer it gets to the end, the faster
it goes.

<stratus46@yahoo.com> wrote in message
news:1be7e70f-c6aa-4159-9691-e19f4e618cb9@l33g2000pri.googlegroups.com...
DaveM wrote:
"bg" <bg@nospam.com> wrote in message news:g9uso7$2jt
$1@news.xmission.com...
bg is correct in that this transformer is a low impedance microphone-to-grid
matching unit. Its turns ratio is about 1:10, meaning that if your primary
line
level voltage is 1VAC, then the transformer's secondary level is going to be
around 10VAC (assuming the impedances allow it). I don't think that's what
you're after.

Of course, you could always send the secondary into a resistive voltage
divider
to get the level back down so the NE5534 input isn't overdriven. Better
still,
connect the transformer in reverse; using the secondary as the input and the
primary as the output. That would reverse the turns ratio to 10:1, so the
output level would be 1/10 the input level. If you need to maintain the
frequency response characteristics of the transformer, then you need to
experiment with source and load impedances that the transformer sees.

A better choice would be a 1:1 ratio transformer; something like a 600:600 ohm
matching transformer.
--
Dave M
What microphone puts out 1 volt? Millivolts is more like it.

 
"Eeysore"
Phil Allison wrote:

** Light mineral oil is not a corrosive "chemical" - you fool.

It WILL degrade certain plastics.

** Light oil attacks no plastic - FOOL.





...... Phil
 
"Jamie" = Maynard A. Philbrook, KA1LPA

A radio ham & demented coder scribbler by trade.

And a rabid usenet menace by night.


....... Phil

** Obviously YOU lack the necessary Midas touch !!!!!

Maybe just a little WD40 down the shaft will do the trick - not a whole
flood of it mind you.

Don't want that precious console to wind up looking like Venice.....


..... Phil ;-)

WD-40 (fish oil as main ingredient or used to be) dries out.



** WD40 residue is ordinary light oil - whether it evaporates depends
on ambient temperature and local air flow.

At room temp and with no virtually no air flow, that takes years.



Spraying the contacts for suspected electrical issues, only
temporarily fixes, and normally makes it worse afterwards.



** The idea is to clean the surfaces and flush away contaminants.

Nothing to do with mysterious "electrical issues ".



Since most chemicals tend to deteriorate the contact surfaces


** Light mineral oil is not a corrosive "chemical" - you fool.


and allows for pitted areas that no longer receives regular wiping from
the
switch action, erosion sets in.


** A coating of light oil protects the metal surfaces by excluding
moisture and air - you colossally stupid ASS .

Go away.



...... Phil


I can see your all talk and no experience pecker head!.. this just proves
it..


http://webpages.charter.net/jamie_5"
 
"Eeysore" ...
"Jamie" = Maynard A. Philbrook, KA1LPA
A radio ham & demented coder scribbler by trade.
Phil Allison wrote:
"Eeysore"

I'm repairing a Midas Venice mixing console. Try and avoid doing so.
It's a nightmare

Despite the agent's tech insisting that the 'solo' switches are 'self
cleaning', no amount of exercising them will prevent 2 of them behaving
intermittently.

** Obviously YOU lack the necessary Midas touch !!!!!

Maybe just a little WD40 down the shaft will do the trick - not a
whole
flood of it mind you.

Don't want that precious console to wind up looking like Venice.....

WD-40 (fish oil as main ingredient or used to be) dries out.

Spraying the contacts for suspected electrical issues, only
temporarily fixes, and normally makes it worse afterwards.

Which is why I won't be doing that.

** Wot an imbecile.



....... Phil
 
On 2008-09-08, Ross Herbert <rherber1@bigpond.net.au> wrote:
:Ross...good idea but not an option because we want the sound heard by
:all...approximately 15 people at a time. We already have and use dual & triple
:stethoscopes but they mean the task has to be repeated over and over whereas if
:we could just broadcast for all to hear at once...presto!
I see. Looks to me like your best and easiest solution is the medical grade
isolation transformer then.
Why not just use active speakers which are powered by batteries?
 
In article <KtmdnSE7OOm82VjVnZ2dnUVZ_uGdnZ2d@earthlink.com>,
Michael A. Terrell <mike.terrell@earthlink.net> wrote:

"Dave Plowman (News)" wrote:

Jeff Liebermann <jeffl@cruzio.com> wrote:

Dry joints? I've never had to lubricate my solder connections.

It's what describes a failed solder joint as well as anything - they
can look sort of dried out.

That is called a 'cold solder joint' in the US, because it is
typically caused by too low of a soldering temperature to make a good
joint.
Don't you talk about 'wetting' when solder flows? Turns from a solid to a
liquid? But whatever - either description works for me.

FWIW I'm not sure all failed joints are caused by too low a temp - you see
them on factory soldered boards too. Famously like round a LOPT - where
the vibration and heat causes the problem.

--
*Seen it all, done it all, can't remember most of it*

Dave Plowman dave@davenoise.co.uk London SW
To e-mail, change noise into sound.
 
"EricM" <ew_morr@hotmail.com> wrote in message
news:22f05a08-1559-4449-a57e-eebe29fd0441@m44g2000hsc.googlegroups.com...
On Sep 7, 8:38 pm, "DaveM" <masondg4...@comcast99.net> wrote:
TheOPsaid he had line-level audio... not a mike.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in
the
address)

Life is like a roll of toilet paper; the closer it gets to the end, the faster
it goes.

stratu...@yahoo.com> wrote in message

news:1be7e70f-c6aa-4159-9691-e19f4e618cb9@l33g2000pri.googlegroups.com...DaveM
wrote:

"bg" <b...@nospam.com> wrote in message news:g9uso7$2jt
$...@news.xmission.com...



bg is correct in that thistransformeris a low impedance microphone-to-grid
matching unit. Its turns ratio is about 1:10, meaning that if your primary
line
level voltage is 1VAC, then thetransformer'ssecondary level is going to be
around 10VAC (assuming the impedances allow it). I don't think that's what
you're after.

Of course, you could always send the secondary into a resistive voltage
divider
to get the level back down so the NE5534inputisn't overdriven. Better
still,
connect thetransformerin reverse; using the secondary as theinputand the
primary as the output. That would reverse the turns ratio to 10:1, so the
output level would be 1/10 theinputlevel. If you need to maintain the
frequency response characteristics of thetransformer, then you need to
experiment with source and load impedances that thetransformersees.

A better choice would be a 1:1 ratiotransformer; something like a 600:600
ohm
matchingtransformer.
--
Dave M

What microphone puts out 1 volt? Millivolts is more like it.

I was intending to use it as a line level input, however I tried it
and got nothing. Removed it and patched the line level input directly
to the R/C network at the input of the first opamp and I get a very
low level signal but adjusting the level pot doesn't seem to do
anything. Will try the 600:600.


Sounds like your opamp circuit isn't working... or not wired correctly. Is it
possible for you to post a schematic of your circuit?
alt.binaries.schematics.electronic is a good place to post it. If you can do
ASCII art, just post it here.


--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in the
address)

Life is like a roll of toilet paper; the closer it gets to the end, the faster
it goes.
 
EricM wrote in message ...
On Sep 8, 12:37 pm, "DaveM" <masondg4...@comcast99.net> wrote:
"EricM" <ew_m...@hotmail.com> wrote in message

news:22f05a08-1559-4449-a57e-eebe29fd0441@m44g2000hsc.googlegroups.com...
On Sep 7, 8:38 pm, "DaveM" <masondg4...@comcast99.net> wrote:



TheOPsaid he had line-level audio... not a mike.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate
characters in
the
address)

Life is like a roll of toilet paper; the closer it gets to the end, the
faster
it goes.

stratu...@yahoo.com> wrote in message


news:1be7e70f-c6aa-4159-9691-e19f4e618cb9@l33g2000pri.googlegroups.com...Da
veM
wrote:

"bg" <b...@nospam.com> wrote in message news:g9uso7$2jt
$...@news.xmission.com...

bg is correct in that thistransformeris a low impedance
microphone-to-grid
matching unit. Its turns ratio is about 1:10, meaning that if your
primary
line
level voltage is 1VAC, then thetransformer'ssecondary level is going
to be
around 10VAC (assuming the impedances allow it). I don't think that's
what
you're after.

Of course, you could always send the secondary into a resistive
voltage
divider
to get the level back down so the NE5534inputisn't overdriven. Better
still,
connect thetransformerin reverse; using the secondary as theinputand
the
primary as the output. That would reverse the turns ratio to 10:1, so
the
output level would be 1/10 theinputlevel. If you need to maintain the
frequency response characteristics of thetransformer, then you need to
experiment with source and load impedances that thetransformersees.

A better choice would be a 1:1 ratiotransformer; something like a
600:600
ohm
matchingtransformer.
--
Dave M

What microphone puts out 1 volt? Millivolts is more like it.



I was intending to use it as a line level input, however I tried it
and got nothing. Removed it and patched the line level input directly
to the R/C network at the input of the first opamp and I get a very
low level signal but adjusting the level pot doesn't seem to do
anything. Will try the 600:600.

Sounds like your opamp circuit isn't working... or not wired correctly.
Is it
possible for you to post a schematic of your circuit?
alt.binaries.schematics.electronic is a good place to post it. If you can
do
ASCII art, just post it here.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters
in the
address)

Life is like a roll of toilet paper; the closer it gets to the end, the
faster
it goes.
Actually I found part of the problem; was using a cutoff switch from
an old parts bin and it was bad. The circuit works fine. Don't
really need an input transformer at all, except the bass seems kind of
thin maybe the 600:600 would correct that. I'm going to be driving an
old tube amp with adjustable inputs at 50, 200 or 500 ohm - would it
be advisable to use a 600:600 on the output and go into the 500 ohm
tap of the tube amp's input? If I understand correctly op amps are
very high impedance on the input and output.

A 5534 can drive a 600 ohm load to about 10 volts peak, so it might do 500
ohms with a little less head room. Keep in mind that your transformer has
two identicle primaries, so you can use one as a primary and one as a
secondary to make a 1 to 1 transformer. You can also use your secondaries
the same way. If you make use of the center taps, you can make a 2 to 1
turns ratio. For example drive one primary with the 5534 and then use half
of the other primary to drive the amps 500 ohm input. This would put alot
less loading on the 5534's output providing the tube amp has enough gain.
You have quite a few options with that transformer but it's hard to say how
best to connect it without knowing the specifics of how much signal you need
into the tube amp. Then again you could also bypass the amps input
transformer???
bg
 
Eeyore wrote in message <48C37B48.397EF24F@hotmail.com>...
I'm repairing a Midas Venice mixing console. Try and avoid doing so.
It's a nightmare

Despite the agent's tech insisting that the 'solo' switches are 'self
cleaning', no amount of exercising them will prevent 2 of them behaving
intermittently.

They are pcb vertical mount types, i.e. the control surface is a series
of large flat double sided boards. From appearance I guessed the
switches to be ALPS but the German parts list gives the following
reference as best as I can decode it.

SCHALTER-TAST 4XUM 1 switch 4pdt

It's a latching type btw.

Any help sourcing same would be appreciated. I only need 2 but knowing
this beast one or two more might pack up !

Thanks, Graham
The Ampex ATR700 decks use a switch that might be the same beast. It is a
PCB that slides into the pushbutton. I've seen spares for sale on the net
for that switch. You might want to search for ampex parts. AMpex mailing
list or something like that.
bg
 
indago <indago@att.net> wrote in message
news:C4EB132B.B24A%indago@att.net...
I have a well used Casio fx-68 pocket calculator that fell apart and the
buttons fell out of it. I retrieved most of them, and am missing the
decimal button that goes under the 2 on the keyboard. The calculator was
built in the early 1980's, and is a really small and flat pocket
scientific
calculator that I used a lot and would like to reassemble and use again.

If somebody knows somebody who has any parts for this calculator, or has
an
old one in a drawer someplace, please let me know. I would like to
purchase
for parts.
I keep expecting my Casio FX 451, bought 80s ?, to fail at the hinged ribbon
as used daily. Great thing about solar cell (only) ones is no battery
problems. Anyone know what sort of construction inside these ? foil ribbon?
fine multistrand?

In your situation
ebay for a non worker
TV repair shop with a box of assorted remotes to rob a button
take a cast and mould , with coloured resin, your own button (top face)
complete with recess for then painted dot and ball-mill the reverse side to
suit


--
Diverse Devices, Southampton, England
electronic hints and repair briefs , schematics/manuals list on
http://home.graffiti.net/diverse:graffiti.net/
 
I had considered getting a reverse mortgage when I hit 62, not so much for
the money, but to avoid having to continue to pay off my regular mortgage.
As I have no dependents, I wouldn't mind the bank having my home when I
died.

But I had doubts about how it worked, or what it was in the first place
(despite having watched the Robert Wagner DVD).

The current Consumer Reports has a brief piece on reverse mortgages, and
assuming it's correct, they're a major ripoff.

They're not really a "reverse" mortgage (whatever that is), but a mortgage
on any remaining unpaid part of your original mortgage, plus the amount of
the equity you borrow. Fees are huge (up to 5% of the home's market value!)
and interest rates unbelievable (CR says as high as 6% -- a month!).

Frankly, a reverse mortgage _seems_ to make sense only if you really need
the money, you have no one to leave the house to, and you expect to die in
the next couple of years. Maybe.

I'm going to check into reverse mortgages, but I suspect the only people
they benefit are the lending institutions.
 
"EricM" <ew_morr@hotmail.com> wrote in message
news:fb467a68-e40d-4d9f-acfa-179fd8c949c4@l43g2000hsh.googlegroups.com...
On Sep 8, 12:37 pm, "DaveM" <masondg4...@comcast99.net> wrote:
"EricM" <ew_m...@hotmail.com> wrote in message

news:22f05a08-1559-4449-a57e-eebe29fd0441@m44g2000hsc.googlegroups.com...
On Sep 7, 8:38 pm, "DaveM" <masondg4...@comcast99.net> wrote:



TheOPsaid he had line-level audio... not a mike.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in
the
address)

Life is like a roll of toilet paper; the closer it gets to the end, the
faster
it goes.

stratu...@yahoo.com> wrote in message

news:1be7e70f-c6aa-4159-9691-e19f4e618cb9@l33g2000pri.googlegroups.com...DaveM
wrote:

"bg" <b...@nospam.com> wrote in message news:g9uso7$2jt
$...@news.xmission.com...

bg is correct in that thistransformeris a low impedance microphone-to-grid
matching unit. Its turns ratio is about 1:10, meaning that if your
primary
line
level voltage is 1VAC, then thetransformer'ssecondary level is going to be
around 10VAC (assuming the impedances allow it). I don't think that's
what
you're after.

Of course, you could always send the secondary into a resistive voltage
divider
to get the level back down so the NE5534inputisn't overdriven. Better
still,
connect thetransformerin reverse; using the secondary as theinputand the
primary as the output. That would reverse the turns ratio to 10:1, so the
output level would be 1/10 theinputlevel. If you need to maintain the
frequency response characteristics of thetransformer, then you need to
experiment with source and load impedances that thetransformersees.

A better choice would be a 1:1 ratiotransformer; something like a 600:600
ohm
matchingtransformer.
--
Dave M

What microphone puts out 1 volt? Millivolts is more like it.



I was intending to use it as a line level input, however I tried it
and got nothing. Removed it and patched the line level input directly
to the R/C network at the input of the first opamp and I get a very
low level signal but adjusting the level pot doesn't seem to do
anything. Will try the 600:600.

Sounds like your opamp circuit isn't working... or not wired correctly. Is it
possible for you to post a schematic of your circuit?
alt.binaries.schematics.electronic is a good place to post it. If you can do
ASCII art, just post it here.

--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in
the
address)

Life is like a roll of toilet paper; the closer it gets to the end, the faster
it goes.
Actually I found part of the problem; was using a cutoff switch from
an old parts bin and it was bad. The circuit works fine. Don't
really need an input transformer at all, except the bass seems kind of
thin maybe the 600:600 would correct that. I'm going to be driving an
old tube amp with adjustable inputs at 50, 200 or 500 ohm - would it
be advisable to use a 600:600 on the output and go into the 500 ohm
tap of the tube amp's input? If I understand correctly op amps are
very high impedance on the input and output.


Actually, an opamp circuit's input impedance is largely dependent on the values
of the components around the opamp. The op-amp is basically a differential
amplifier having a large voltage gain, very high input impedance (megohms) and
low output impedance (ohms).

Consider the simple inverting amp below. The input impedance of this circuit
would be Ra in parallel with Rf. The output impedance is determined by the
opamp's internal characteristics. Most general purpose amps have output
impedance less than 100 ohms. To get the highest peak-to-peak signal swing at
the output, the opamp should be looking into 2k or more (again, highly dependent
on the opamp). Your NE5534 should be able to drive the 500 ohm input, but you
might not get full signal swing on the output (the NE5534 is spec'ed to drive
600 ohms).

Using a transformer interface between your opamp circuit and the tube amp's
input isn't necessary unless you have a ground loop or noise problem. The
transformer (600:600) should help eliminate that. That statement would apply to
the opamp's input also.

One thing to remember is that the transformer doesn't create the impedances; it
just transforms them. IOW, if you have a transformer with a 1:1 turns ratio
(such as the 600:600 ohm unit), then if you connect it to the opamp's output,
and drive the tube amp's 50 ohm input, the opamp will see 50 ohms at its output
(NOT 600 ohms). The turns ratio is the determining characteristic. The
impedance spec of a signal transformer is just an approximation of the circuit
impedances that it will work best in.
Following up on that , if you have a transformer with a 1:10 turns ratio, and
connect it between the opamp's output and the tube amp's 50 ohm input, the opamp
will see a reflected impedance of 5000 ohms.
Read more transformer theory at
http://books.google.com/books?id=PCotNzaNqD4C&pg=RA1-PA92&lpg=RA1-PA92&dq=transformer+%22turns+ratio%22+impedance&source=web&ots=gB9jtI5uxP&sig=Dw8Acub_bw2gczTqfC25l2kSl_0&hl=en&sa=X&oi=book_result&resnum=6&ct=result#PRA1-PA92,M1


View in a fixed-width font such as Courier.



+------+
+--------+ Rf +-------+
| +------+ |
| |
| |
+-----+ | |\ |
------+ Ra +--+--------|-\ |
+-----+ | \ |
| \----------+------->
+------|+ /
| | /
| | /
--+-- |/
---
-


--
Dave M
MasonDG44 at comcast dot net (Just substitute the appropriate characters in the
address)

Life is like a roll of toilet paper; the closer it gets to the end, the faster
it goes.
 
In article <3606-48C6FD05-1916@storefull-3251.bay.webtv.net>,
cuhulin@webtv.net wrote:

Does anybody know where I can buy a wireless speaker for my tv set.I
want to place the speaker by my couch and turn down the tv set's built
in speaker sound.
cuhulin
Radio Shack. You remember their slogan: "You've got questions. We've got
C students wearing ties."
 
"Ardent" <iam@here.com.invalid> wrote in message
news:d20dc45v099rscl6l107ddqrq57lag9umf@4ax.com...
Hi Friends

Someone plugged my Dream machine (rated 110 VAC) into a 220 VAC outlet
and the transformer primary got trashed. Since I will be living here
for a while I thought of getting a transformer made here locally (very
cheap, honest).

There are two independent secondaries and will thank anyone who can
tell me what the outputs are.

--
Thanks for your time and attention

Ardent
The primary of the transformer being trashed, might very well be the least
of your worries. Power transformers are pretty robust, and it is likely that
the primary survived for at least some tens of miliseconds before failing,
and possibly more than that. This means that for this period, the secondary
voltages will have been double their nominal value, which could have done
rather more serious downstream damage ...

Sorry to throw this one in, but it's a problem that we see fairly regularly
in the UK with visitors from the US, and often they think it is just going
to be a simple power problem like a fuse, and it turns out to be rather more
serious. You might be one of the lucky ones and have gotten away with it.
Let's hope :)

Arfa
 
<mister@myplace.com> wrote in message
news:iprec4pt2j3irm5vg5qid6ar88jgn2jir1@4ax.com...
On Sat, 6 Sep 2008 14:36:12 -0700 (PDT), "Josh9.0"
squalene9er@hotmail.com> wrote:

No I haven't!
Thanks for the tip, and thanks for the quick reply!
I'll go and try it now.
It has a bunch of different voltages out, and they're labelled on the
PCB!
I guess I should look for ripple on what should be DC, right??
Then trace it back to the offending cap(s).
Then go buy some new ones of those only.

BTW: It has a main voltage going to all the keys of 46V which measures
43V.

Have you ever heard the hum when you pull the cord on a guitar
amplifier, or some cable going to your home stereo? What do you get?
A loud hum! This is momentarily because the ground is lost. Might
you have a loose ground to one of the boards ahead of the audio
amplifier (or in it)? There should be a potentiometer for volume
control at the head (pre-amp) section of the amplifier. Remove the
wire (or cut the PCB trace) where the input goes into the amp.
Connect an auxilliary source, such as the output of a cd player or a
radio tuner, to that point. Do you hear a hum? If yes, the problem
is in the amp itself. If not, the problem is ahead of the amp.

Of course, check the power supply first, and LOOK FOR LOOSE GROUNDS.

Mister
I've already said about the bad grounds twice so far in this thread, and
once I think that he has replied that he hasn't found any, but I'm with you
there. However, I don't think that he has the necessary professional
background in service, to be able to run down a problem like this by
disconnecting things, and running alternate grounds ... :-\

Arfa
 

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