sci.electronics.repair - 16 new messages in 8 topics - digest

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

sci.electronics.repair@googlegroups.com

Today's topics:

==============================================================================
TOPIC: HP Deskjet 990Cxi prints `in white!'
http://groups.google.com/group/sci.electronics.repair/t/e9b76061bef0d6b2?hl=en
==============================================================================

== 1 of 3 ==
Date: Sat, Sep 11 2010 11:48 am
From: PlainBill47@yawho.com

On Fri, 10 Sep 2010 10:07:18 -0700 (PDT), Merciadri Luca
<merciadriluca@gmail.com> wrote:

>Hi,
>
>I've got an old Hp Deskjet 990Cxi which suddenly decided to print
>nothing. When I send a document to the printer, it behaves as before
>(paper is taken, cartridges move, etc.), but the resulting page is
>still as white as it was before printing.
>
>The problem does not come from the computer, because I tried several
>things. Among them,
>* Printing test: holding the resume button for more than 4 secs. makes
>it print, but the page is still white;
>* Technical test: having the power button hold, and then pressing 4
>times the resume button. A page seems to be printed (same behaviour),
>but, just as before, nothing is printed, despite cartridges'
>movements, etc.
>
>Any idea? I need to make it work.
>
>Thanks.
HP cartridges eject the ink by applying a pulse of electricity to a
heating element in the cartridge. There would be one element for each
color in a multi-color cartridge. Since you have tried different new
cartridges, and a self-test you have eliminated the cartridges and the
computer. That leaves the cause as something internal to the printer.
This would be a failure of the printer electronics, a flaw in the
cable connecting the print head to the electronics board, or possibly
contamination of the contact pad on the printer carriage.

PlainBill

== 2 of 3 ==
Date: Sat, Sep 11 2010 2:41 pm
From: Jamie

PlainBill47@yawho.com wrote:

> On Fri, 10 Sep 2010 10:07:18 -0700 (PDT), Merciadri Luca
> <merciadriluca@gmail.com> wrote:
>
>
>>Hi,
>>
>>I've got an old Hp Deskjet 990Cxi which suddenly decided to print
>>nothing. When I send a document to the printer, it behaves as before
>>(paper is taken, cartridges move, etc.), but the resulting page is
>>still as white as it was before printing.
>>
>>The problem does not come from the computer, because I tried several
>>things. Among them,
>>* Printing test: holding the resume button for more than 4 secs. makes
>>it print, but the page is still white;
>>* Technical test: having the power button hold, and then pressing 4
>>times the resume button. A page seems to be printed (same behaviour),
>>but, just as before, nothing is printed, despite cartridges'
>>movements, etc.
>>
>>Any idea? I need to make it work.
>>
>>Thanks.
>
> HP cartridges eject the ink by applying a pulse of electricity to a
> heating element in the cartridge. There would be one element for each
> color in a multi-color cartridge. Since you have tried different new
> cartridges, and a self-test you have eliminated the cartridges and the
> computer. That leaves the cause as something internal to the printer.
> This would be a failure of the printer electronics, a flaw in the
> cable connecting the print head to the electronics board, or possibly
> contamination of the contact pad on the printer carriage.
>
> PlainBill
Most likely the the power supply for the pulse current source.

== 3 of 3 ==
Date: Sat, Sep 11 2010 3:29 pm
From: Merciadri Luca

On Sep 11, 11:41 pm, Jamie
<jamie_ka1lpa_not_valid_after_ka1l...@charter.net> wrote:
> PlainBil...@yawho.com wrote:
> > On Fri, 10 Sep 2010 10:07:18 -0700 (PDT), Merciadri Luca
> > <merciadril...@gmail.com> wrote:
>
> >>Hi,
>
> >>I've got an old Hp Deskjet 990Cxi which suddenly decided to print
> >>nothing. When I send a document to the printer, it behaves as before
> >>(paper is taken, cartridges move, etc.), but the resulting page is
> >>still as white as it was before printing.
>
> >>The problem does not come from the computer, because I tried several
> >>things. Among them,
> >>* Printing test: holding the resume button for more than 4 secs. makes
> >>it print, but the page is still white;
> >>* Technical test: having the power button hold, and then pressing 4
> >>times the resume button. A page seems to be printed (same behaviour),
> >>but, just as before, nothing is printed, despite cartridges'
> >>movements, etc.
>
> >>Any idea? I need to make it work.
>
> >>Thanks.
>
> > HP cartridges eject the ink by applying a pulse of electricity to a
> > heating element in the cartridge. There would be one element for each
> > color in a multi-color cartridge. Since you have tried different new
> > cartridges, and a self-test you have eliminated the cartridges and the
> > computer. That leaves the cause as something internal to the printer.
> > This would be a failure of the printer electronics, a flaw in the
> > cable connecting the print head to the electronics board, or possibly
> > contamination of the contact pad on the printer carriage.
>
> > PlainBill
>
> Most likely the the power supply for the pulse current source.

Well, I moved the printer and washed my cartridges with alcohol. They
were quite old (but new too: just never used for many), and using heat
and alcohol, they worked perfectly. Thanks. (I had not used the
printer for a while.)

==============================================================================
TOPIC: CTC 187 strange volume problem
http://groups.google.com/group/sci.electronics.repair/t/db930b344d3fc777?hl=en
==============================================================================

== 1 of 3 ==
Date: Sat, Sep 11 2010 11:56 am
From: Meat Plow

On Sat, 11 Sep 2010 11:45:29 -0700, klem kedidelhopper wrote:

> I got a CTC 187 in with a complaint that after five minutes or so the
> volume gradually decreases by itself. I was thinking possibly tact
> switches but someone else said that it could be a bad eprom. I was
> wondering how one might go about isolating this problem?. I ran this set
> for a few days and never noticed a problem with the sound. I was about
> to call the guy and have him pick it up and suggest that perhaps the
> problem was the cable box when I mistakenly went to bed one night and
> left it running in the shop. I woke up the next morning and realizing
> that the set was on the first thing I noticed was that there was no
> sound coming from the shop. I took a look at the screen and noticed that
> every 2 or 3 seconds a volume bar would appear then disappear as thouh
> the set was being addressed by either the front panel tact switch or the
> remote. The volume indicator would show the sound to be all the way down
> each time it would appear as it indeed was. I tried raising the sound up
> and although the volume bar appeared and it did increment up it then
> afterwards immediatly slowly incremented down by itself.agsin. I haven't
> opened this thing yet as I really wanted to confirm his complaint first.
> Now that I have and considering what I've observed, does anyone think
> that the presence of the volume bar points to a leaky tact switch? Or
> could the volume bar and subsequent function activation be initiated by
> either a bad T chip or the processor? .
> I guess what I'm wondering is if there is any way that the set could
> produce a volume bar without the appropriate infrafed signal coming
> through the IR receiver or the chip being addressed directly through the
> tact switch? Thanks, Lenny

Unplug the IR receiver and tact switches ( P/J3001)then retest.

--
Live Fast, Die Young and Leave a Pretty Corpse

== 2 of 3 ==
Date: Sat, Sep 11 2010 6:25 pm
From: klem kedidelhopper

On Sep 11, 2:56 pm, Meat Plow <mhyw...@yahoo.com> wrote:
> On Sat, 11 Sep 2010 11:45:29 -0700, klem kedidelhopper wrote:
> > I got a CTC 187 in with a complaint that after five minutes or so the
> > volume gradually decreases by itself. I was thinking possibly tact
> > switches but someone else said that it could be a bad eprom. I was
> > wondering how one might go about isolating this problem?. I ran this set
> > for a few days and never noticed a problem with the sound. I was about
> > to call the guy and have him pick it up and suggest that perhaps the
> > problem was the cable box when I mistakenly went to bed one night and
> > left it running in the shop. I woke up the next morning and realizing
> > that the set was on the first thing I noticed was that there was no
> > sound coming from the shop. I took a look at the screen and noticed that
> > every 2 or 3 seconds a volume bar would appear then disappear as thouh
> > the set was being addressed by either the front panel tact switch or the
> > remote. The volume indicator would show the sound to be all the way down
> > each time it would appear as it indeed was. I tried raising the sound up
> > and although the volume bar appeared and it did increment up it then
> > afterwards immediatly slowly incremented down by itself.agsin. I haven't
> > opened this thing yet as I really wanted to confirm his complaint first.
> > Now that I have and considering what I've observed, does anyone think
> > that the presence of the volume bar points to a leaky tact switch? Or
> > could the volume bar and subsequent function activation be initiated by
> > either a bad T chip or the processor? .
> > I guess what I'm wondering is if there is any way that the set could
> > produce a volume bar without the appropriate infrafed signal coming
> > through the IR receiver or the chip being addressed directly through the
> > tact switch? Thanks, Lenny
>
> Unplug the IR receiver and tact switches ( P/J3001)then retest.
>
> --
> Live Fast, Die Young and Leave a Pretty Corpse- Hide quoted text -
>
> - Show quoted text -

The tact switches seem to be the general consensus here. I really
appreciate the advice. I have a theory on this problem that I would
like to share. I also service commercial apartment house intercom
systems. The apartment stations used in these systems are simply a 45
ohm speaker and three NO pushbutton switches. The switches are:
"talk", "listen" and "door", (The last of which buzzes the front door
solenoid to let people into the building.

Quite often I'm called out to one of these buildings to troubleshoot
what seems like an impossibla weird problem. It may be that the lobby
door solenoid is buzzing constantly, or perhaps the lobby speaker is
crackling, or sometimes you find that you can listen to someones
apartment constantly through the lobby speaker. Every apartment
station sits on a three wire common trunk line so natually the
occurance of any of these problems disables the entire building.

Many of these apartment stations use a form of a tact switch that just
fails at tmes for no reason. Disconnecting that problem apartment
station from the common trunk line in every case restores proper
intercom function through the building. One particular 24 unit complex
I service has four trunk wires in parallel each serving 6
apartments.Once I've isolated the problem down to a particular trunk
line or group of six I will ask the building manager who the smokers
are in those six apartments. Nine times ot of ten the problem switches
are in the station that has been exposed to heavy doses of tar and
nicotine.

My theory is that the smoke residue or the dust that clings to it must
be conductive and therefore provides a high resistace short across the
open switch. This has happened on more than one occaision so I don't
believe that it is coincidence.

As it happens this TV customer is a heavy smoker too. The chassis
had a thick "blanket" of
sticky dust that I had to blow off with my vacuum cleaner before I
could even put this on my bench.
For fifteen years this guy has been blowing smoke at this set. I
think that it finally suffocated. Just
a theory. What do you think? Lenny

== 3 of 3 ==
Date: Sat, Sep 11 2010 6:51 pm
From: "hr(bob) hofmann@att.net"

On Sep 11, 8:25 pm, klem kedidelhopper <captainvideo462...@gmail.com>
wrote:
> On Sep 11, 2:56 pm, Meat Plow <mhyw...@yahoo.com> wrote:
>
>
>
>
>
> > On Sat, 11 Sep 2010 11:45:29 -0700, klem kedidelhopper wrote:
> > > I got a CTC 187 in with a complaint that after five minutes or so the
> > > volume gradually decreases by itself. I was thinking possibly tact
> > > switches but someone else said that it could be a bad eprom. I was
> > > wondering how one might go about isolating this problem?. I ran this set
> > > for a few days and never noticed a problem with the sound. I was about
> > > to call the guy and have him pick it up and suggest that perhaps the
> > > problem was the cable box when I mistakenly went to bed one night and
> > > left it running in the shop. I woke up the next morning and realizing
> > > that the set was on the first thing I noticed was that there was no
> > > sound coming from the shop. I took a look at the screen and noticed that
> > > every 2 or 3 seconds a volume bar would appear then disappear as thouh
> > > the set was being addressed by either the front panel tact switch or the
> > > remote. The volume indicator would show the sound to be all the way down
> > > each time it would appear as it indeed was. I tried raising the sound up
> > > and although the volume bar appeared and it did increment up it then
> > > afterwards immediatly slowly incremented down by itself.agsin. I haven't
> > > opened this thing yet as I really wanted to confirm his complaint first.
> > > Now that I have and considering what I've observed, does anyone think
> > > that the presence of the volume bar points to a leaky tact switch? Or
> > > could the volume bar and subsequent function activation be initiated by
> > > either a bad T chip or the processor? .
> > > I guess what I'm wondering is if there is any way that the set could
> > > produce a volume bar without the appropriate infrafed signal coming
> > > through the IR receiver or the chip being addressed directly through the
> > > tact switch? Thanks, Lenny
>
> > Unplug the IR receiver and tact switches ( P/J3001)then retest.
>
> > --
> > Live Fast, Die Young and Leave a Pretty Corpse- Hide quoted text -
>
> > - Show quoted text -
>
> The tact switches seem to be the general consensus here. I really
> appreciate the advice. I have a theory on this problem that I would
> like to share. I also service commercial apartment house intercom
> systems. The apartment stations used in these systems are simply a 45
> ohm speaker and three NO pushbutton switches. The switches are:
> "talk", "listen" and "door", (The last of which buzzes the front door
> solenoid to let people into the building.
>
> Quite often I'm called out to one of these buildings to troubleshoot
> what seems like an impossibla weird problem. It may be that the lobby
> door solenoid is buzzing constantly, or perhaps the lobby speaker is
> crackling, or sometimes you find that you can listen to someones
> apartment constantly through the lobby speaker. Every apartment
> station sits on a three wire common trunk line so natually the
> occurance of any of these problems disables the entire building.
>
> Many of these apartment stations use a form of a tact switch that just
> fails at tmes for no reason. Disconnecting that problem apartment
> station from the common trunk line in every case restores proper
> intercom function through the building. One particular 24 unit complex
> I service has four trunk wires in parallel each serving 6
> apartments.Once I've isolated the problem down to a particular trunk
> line or group of six I will ask the building manager who the smokers
> are in those six apartments. Nine times ot of ten the problem switches
> are in the station that has been exposed to heavy doses of tar and
> nicotine.
>
> My theory is that the smoke residue or the dust that clings to it must
> be conductive and therefore provides a high resistace short across the
> open switch. This has happened on more than one occaision so I don't
> believe that it is coincidence.
>
> As it happens this TV customer is a heavy smoker too. The chassis
> had a thick "blanket" of
> sticky dust that I had to blow off with my vacuum cleaner before I
> could even put this on my bench.
> For fifteen years this guy has been blowing smoke at this set. I
> think that it finally suffocated. Just
> a theory. What do you think? Lenny- Hide quoted text -
>
> - Show quoted text -

You proabaly couldn't win this case in a court of law, but it sure
seems very likely that you are on the right track.

==============================================================================
TOPIC: Monitor screen dark but LED stays green.
http://groups.google.com/group/sci.electronics.repair/t/a3e1f398f7842702?hl=en
==============================================================================

== 1 of 2 ==
Date: Sat, Sep 11 2010 11:59 am
From: PlainBill47@yawho.com

On Sat, 11 Sep 2010 19:26:47 +0530, "Pimpom" <Pimpom@invalid.invalid>
wrote:

>My 7-year old CRT monitor has developed an intermittent fault.
>Sometimes the screen goes black but the power LED remains green
>(doesn't turn amber). A sharp rap often restores the display.
>When it decides to act up, the LED stays green even when it's
>turned on for several minutes while disconnected from the
>computer.
>
>I did a lot of repair work on a wide range of electronic products
>up to the early nineties, but I'm quite rusty now. I've opened up
>the monitor but can't see anything obvious in the way of a dry
>solder or loose connector. The tube heater glows all the time.
>The signal cable goes first to the tube base PCB and connections
>to the main PCB are with two flat cables.
>
>Which signal line does a computer monitor use to detect the
>presence of a signal? Where do you think I should start looking?
>Thanks in advance for any input.
>
It probably uses one of the sync lines. An intelligent approach would
be to check resources such as www.elektrotanya.com and
http://english.electronica-pt.com/ to see if you can find a schematic.
Failing there, I would use a lighted magnifier and carefully examine
the circuit boards for cracks, bad solder joints, etc. AFTER reseating
all connectors.

Or you c ould get a rubber mallet to whack the monitor each time it
fails.

PlainBill

== 2 of 2 ==
Date: Sat, Sep 11 2010 1:08 pm
From: "Pimpom"

PlainBill47@yawho.com wrote:
> On Sat, 11 Sep 2010 19:26:47 +0530, "Pimpom"
> <Pimpom@invalid.invalid>
> wrote:
>
>> My 7-year old CRT monitor has developed an intermittent fault.
>> Sometimes the screen goes black but the power LED remains
>> green
>> (doesn't turn amber). A sharp rap often restores the display.
>> When it decides to act up, the LED stays green even when it's
>> turned on for several minutes while disconnected from the
>> computer.
>>
>> I did a lot of repair work on a wide range of electronic
>> products
>> up to the early nineties, but I'm quite rusty now. I've opened
>> up
>> the monitor but can't see anything obvious in the way of a dry
>> solder or loose connector. The tube heater glows all the time.
>> The signal cable goes first to the tube base PCB and
>> connections
>> to the main PCB are with two flat cables.
>>
>> Which signal line does a computer monitor use to detect the
>> presence of a signal? Where do you think I should start
>> looking?
>> Thanks in advance for any input.
>>
> It probably uses one of the sync lines.

Thanks.

> An intelligent approach would
> be to check resources such as www.elektrotanya.com and
> http://english.electronica-pt.com/ to see if you can find a
> schematic.

I downloaded the service manual (Hungarian, it seems) from
elektrotanya.com after I made my initial post, and another from
electronica-pt.com just now after reading your post. They turned
out to be identical. But my chassis is significantly different
from them although the model number and the FCC ID match.

> Failing there, I would use a lighted magnifier and carefully
> examine
> the circuit boards for cracks, bad solder joints, etc. AFTER
> reseating
> all connectors.

Already did that. No luck. I have a 16mm film projector lens
which is more powerful and optically better than a magnifying
glass. Seems I'll have to do this the hard way - step by step
analysis. Electronics is both a profession and a hobby with me
and, being my own boss, I can afford the time. Luckily, right now
I don't have any major design project that can't wait for a few
days.

>
> Or you c ould get a rubber mallet to whack the monitor each
> time it
> fails.

There's always that, of course :-)

==============================================================================
TOPIC: Pioneer 100 disc CD player problems
http://groups.google.com/group/sci.electronics.repair/t/5263ce04af75aa85?hl=en
==============================================================================

== 1 of 3 ==
Date: Sat, Sep 11 2010 1:01 pm
From: klem kedidelhopper

This unit was given to me with the complaint that it would
intermittently "skip". I did confirm this to be so and I subsequently
slightly increased the setting on the laser pot. The unit seemed to be
OK after that and I put it away for several months. I now have a use
for it and got it out of the closet and loaded it up with CD's only to
find that its doing the same thing once again. The strange thing is
that some CD's seem to be affected worse than others. In fact some
CD's will play fine and others have skips many times in the same
places on the same particular disc when repeated plays are attempted,
while other discs are not recognized at all. There are random skips at
times on some CD's as well. I know that some CDR's could be a problem
with some older machines and so we are not attempting to play any of
those. I was hoping to note the particular CD, track, and time into
the recording and if there was failure repeatability, use that to
determine if my adjustments solve the problem but I don't know if this
method would work or not. Does anyone have any opinions on that? Could
some sections of a CD be harder for what I'm assuming to be a weak
laser to "see" than others? Can someone please explain this
phenomenon to me? I'm going to try to tweak this thing again but I
would just appreciate a better understanding of this. Thanks, Lenny

== 2 of 3 ==
Date: Sat, Sep 11 2010 1:07 pm
From: Meat Plow

On Sat, 11 Sep 2010 13:01:09 -0700, klem kedidelhopper wrote:

> This unit was given to me with the complaint that it would
> intermittently "skip". I did confirm this to be so and I subsequently
> slightly increased the setting on the laser pot. The unit seemed to be
> OK after that and I put it away for several months. I now have a use for
> it and got it out of the closet and loaded it up with CD's only to find
> that its doing the same thing once again. The strange thing is that some
> CD's seem to be affected worse than others. In fact some CD's will play
> fine and others have skips many times in the same places on the same
> particular disc when repeated plays are attempted, while other discs are
> not recognized at all. There are random skips at times on some CD's as
> well. I know that some CDR's could be a problem with some older machines
> and so we are not attempting to play any of those. I was hoping to note
> the particular CD, track, and time into the recording and if there was
> failure repeatability, use that to determine if my adjustments solve the
> problem but I don't know if this method would work or not. Does anyone
> have any opinions on that? Could some sections of a CD be harder for
> what I'm assuming to be a weak laser to "see" than others? Can someone
> please explain this phenomenon to me? I'm going to try to tweak this
> thing again but I would just appreciate a better understanding of this.
> Thanks, Lenny

Check for dust in the optics. Sometimes you can luck out adjusting a
laser by the seat of your pants, sometimes not.

--
Live Fast, Die Young and Leave a Pretty Corpse

== 3 of 3 ==
Date: Sat, Sep 11 2010 1:39 pm
From: "William Sommerwerck"

Skipping can be due to a deteriorating laser diode. I would see about
replacing the assembly.

==============================================================================
TOPIC: Looking for oscilloscope manual- Dumont 329
http://groups.google.com/group/sci.electronics.repair/t/0a79d876bde58587?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Sep 11 2010 3:03 pm
From: lsolomon13

If any has a copy of this, please let me know. I have been looking all
over for it.

Thanks,
Lori

==============================================================================
TOPIC: LORAN C
http://groups.google.com/group/sci.electronics.repair/t/73c2d1e0342e191b?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Sep 11 2010 4:22 pm
From: Jeff Liebermann

On Fri, 10 Sep 2010 19:48:43 -0700, Jeff Liebermann <jeffl@cruzio.com>
wrote:

>On Thu, 9 Sep 2010 06:32:06 -0700 (PDT), Andy <andysharpe@juno.com>
>wrote:
>> The only way the antenna can be "better" is to have more gain.

A bit more detail on GPS antenna gain that might be of interest. The
usual assumption is that all GPS patch antennas have the same gain.
Nope. From one of my previous rants on iPhone GPS performance:

Sarantel makes ceramic QFA antennas with -2db to -3dBic gain:
<http://www.sarantel.com/downloads/specifications/geohelix-p2.pdf>

For ceramic substrate backed antennas, size is everything. This has
nothing to do with the iPhone 3G antenna, but does explain why a
ceramic substrate quadrifilar antenna has -2dBic gain, while the much
larger air dielectric version has +5dBic gain. I couldn't find
comparative data for various size quadrifilar antenna, but the
following on patch antennas shows the problem:
<http://www.taoglas.com/images/product_images/original_images/TAOGLAS%20-%20GPS%20Active%20Patch%20Antenna%20Application%20Note.pdf>
Typical peak gain for GPS patch antennas on standardized
ground planes are following.
25mm Patch 5 dBi
18mm Patch 2 dBi
15mm Patch 1 dBi
12mm Patch 0.5 dBi
10mm Patch -2 dBi

The effective bandwidth of a GPS antenna is usually measured
by the frequency band below -10dB return loss. A GPS ceramic
patch bandwith narrows with size. Typical bandwidths for
GPS patches are as follows
25*25*4 mm 20 MHz
18*18*4 mm 10 Mhz
15*15*4 mm 8 Mhz
12*12*4 mm 7 MHz
10*10*4 mm 5 MHz
Therefore the smaller the antenna, the more chance it will
have that frequency shifts in the device will cause it to
perform very poorly, thus necessitating that the antenna
bandwidth be retuned to have the effective bandwidth at the
GPS 1.5754 GHz frequency.

--
Jeff Liebermann jeffl@cruzio.com
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

==============================================================================
TOPIC: Warwick Amp tech info ?
http://groups.google.com/group/sci.electronics.repair/t/e3b86b168d4f6b75?hl=en
==============================================================================

== 1 of 2 ==
Date: Sat, Sep 11 2010 6:12 pm
From: "Arfa Daily"

"N_Cook" <diverse@tcp.co.uk> wrote in message
news:i6ffrr$3st$1@news.eternal-september.org...
> N_Cook <diverse@tcp.co.uk> wrote in message
> news:i6fete$o6$1@news.eternal-september.org...
>> Any leads to info on Warwick Tubepath 5.1 500W amplifier or any info on
>> probably NPN TOP66 size devices marked
>> Warwick WA
>> I assume 0340 on the line beneath is datecode for 2003
>>
>>
>>
>>
>
> I was misspelling as warrick, good info on
> http://www.warwickbass.com/media/manuals/Tubepath/TubePath_5-1_from_H20692.p
> df
> and so WA = 2SC5200 it would seem
>
>
>

Goggle says that link is busted ...

Arfa

== 2 of 2 ==
Date: Sun, Sep 12 2010 12:06 am
From: "N_Cook"

Arfa Daily <arfa.daily@ntlworld.com> wrote in message
news:NNVio.83475$Kp4.27280@newsfe22.ams2...
>
>
> "N_Cook" <diverse@tcp.co.uk> wrote in message
> news:i6ffrr$3st$1@news.eternal-september.org...
> > N_Cook <diverse@tcp.co.uk> wrote in message
> > news:i6fete$o6$1@news.eternal-september.org...
> >> Any leads to info on Warwick Tubepath 5.1 500W amplifier or any info on
> >> probably NPN TOP66 size devices marked
> >> Warwick WA
> >> I assume 0340 on the line beneath is datecode for 2003
> >>
> >>
> >>
> >>
> >
> > I was misspelling as warrick, good info on
> >
http://www.warwickbass.com/media/manuals/Tubepath/TubePath_5-1_from_H20692.p
> > df
> > and so WA = 2SC5200 it would seem
> >
> >
> >
>
> Goggle says that link is busted ...
>
> Arfa
>

Thats Goolie for you.
Soft blown 2x 630mA fuses for +/-15V lines so about 1 amp failure due to
someone throwing beer at and into the front switch and pot area and "smoke"
emanating before failure. No source of smoke found yet ,unless from inside
of a pot, would beer give off smoke in its final stages of "frying" ?
Metal pot shafts and metal knobs so springs under knobs , for safety or for
reducing crackle on turning or both ?

Very clear schema etc and compact 300K pdf
other manuals listed there for
Warwick Series
# Overview
# Corvette
* Corvette $$
* Corvette $$ NT Bubinga
* Corvette $$ NT Ash
# Streamer
* Streamer LX
* Streamer Jazzman
* Streamer Stage I
* Streamer Stage II
* Streamer $$
# Thumb
* Thumb Bolt-on
* Thumb (NT)
# Thumb SC
# Infinity
* Infinity NT Birdeye Maple Top
* Infinity NT Flamed Maple Top
# Star Bass II
* Star Bass II Bubinga
* Star Bass II Maple
# Dolphin Pro I
# Stryker
# Katana
# Vampyre NT
# Triumph
+ Special Editions
+ Limited Editions
# Overview
# Corvette NT LTD 2010
# Corvette $$ LTD 2009
# Streamer LX LTD 2008
# Thumb Bolt-on LTD 2007
# Thumb Bolt-on LTD 2006
# Corvette Standard LTD 2005
# FNA Jazzman LTD 2004
# Thumb Bolt-on LTD 2003
# FNA Jazzman LTD 2002
# Thumb Bolt-on LTD 2001
+ Signature Series
# Overview
# Rubert Trujillo Quicksilver Signature
# Robert Trujillo Turquoise Blue Signature
# Bootsy Collins Black Star Signature
# Bootsy Collins Orange Star Signature
# Adam Clayton Reverso Signature
# TM Stevens Signature
# Stuart Zender Signature
# P-Nut III Signature
# P-Nut II Signature
# P-Nut I Signature
# Jack Bruce Signature
# Jack Bruce CRB
# Hellborg Signature Bass
# Jäcki Reznicek Signature
# Buzzard JE Signature
# Nobby Meidel Signature
+ Custom Shop
+ Discontinued Basses
# Overview
# Buzzard BO
# Corvette Pro Line
# Corvette Taranis
# Dolphin SNT TCST
# FNA
# FNA Jazzman
# Fortress Series
# Infinity SNT TCST
# Katana Bolt-on
# Streamer CT
# Streamer LX Broadneck
# Streamer Pro M
# Stryker Mahogany
# Stryker Ziricote
# Thumb Bolt on BN
# Vampyre BO
"Dark Lord"
# Vampyre SNT
o Warwick Pro Series Made in Korea
+ Corvette Standard Bubinga
+ Corvette Standard Ash
o RockBass Series Made in China
+ Overview
+ Streamer Standard
+ Streamer LX
+ Corvette Basic
# Corvette Basic activ
# Corvette Basic passiv
+ Corvette Classic
+ Corvette Premium
+ Corvette $$
+ Fortress
+ Vampyre
o Alien Acoustic Made in Vietnam
+ Warwick Alien
+ Rockbass Alien Standard
+ Rockbass Alien Deluxe
o Amplification
+ Amps
# Overview
# ProFet Series
# TubePath Series
# X-Treme Series
+ Cabinets
# Overview
# Cabinets Pro Series
# Cabinets Neodyme Series
+ Combos
# Overview
# Blue Cab Series
# Semi Professional Series
# Professional Series
# Amps
# Cabinets
+ Hellborg

==============================================================================
TOPIC: Battery charger part
http://groups.google.com/group/sci.electronics.repair/t/c8a9fedf5d5210b0?hl=en
==============================================================================

== 1 of 1 ==
Date: Sat, Sep 11 2010 7:25 pm
From: Grant

On Sat, 11 Sep 2010 12:28:15 -0500, Paul Nelson <drhydro@qwest.net> wrote:

>oops. full-wave, but not bridge.

But you could replace the diodes with a bridge, just ignore either the
plus or minus terminal on bridge and use centre tap of transformer as
per existing circuit. Those high current large bridges are probably
easier to buy and mount on the heatsink than a pair of power diodes.

The unused pair of diodes in the bridge wont do any harm.

Grant.

>On 9/11/10 10:41 AM, Paul Nelson wrote:
>> The part in the first pic ("diode") is a circuit breaker. The two
>> ceramic buttons on the "plate" are the diode rectifiers, that'd be a
>> half-wave bridge configuration.
>>
>> Hope that helps!
>>
>> On 9/10/10 8:53 AM, LSMFT wrote:
>>> Can somebody tell me what this part is?
>>> It's a plate with 2 contacts. 2 12vac outputs from the transformer are
>>> connected to the contacts. The output is the positive charging lead.
>>> The other output of the transformer goes through what looks like a 12v
>>> 12a diode though I'm not sure if it is a diode. Then goes through the
>>> meter to the negative charging lead.
>>> It's an old charger, puts out 13.5vdc on the charger, tapers down to
>>> zero when the battery is charged. Tough charger, dropped it a couple
>>> times on the concrete floor. Unknown maker.
>>>
>>> http://tinypic.com/m/bimp1g/2 Diode
>>> http://tinypic.com/m/bimp6p/2 Plate
>>> http://tinypic.com/m/bimp83/2 Transformer
>>> http://tinypic.com/m/bimp9h/2 Plate contact
>>> http://tinypic.com/m/bimpah/2 Meter connection
>>> http://tinypic.com/m/bimpeb/2 Charger
>>>
>>>
>>>
>>
>>

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