Vintage Synth Repair

Thanks Massada  for  your input on this.  This has been an ongoing problem...I got this thing probably a year ago it looks great but gets no sound at all.  I did some checking on it, got the schematics and found that it appears to have a bad - 15 voltage regulator.  So I try and order the part, it has to cross to this and than cross to this and etc.  Finally I get a pair of regulators that should work, I put one in and it works momentarily and fails toasting a resistor on the way.  I take it to a local tech...They keep it two months and return it unrepaired, they cant find the -15 voltage regulator and suggest designing a new power supply for it - but don't seem eager to do it.  Mainly they tell me not to come back unless "I bring in something from after 1970".  So now I'm back where I started with the damn thing sitting in the corner of the studio collecting dust.  At this point I'm looking for anything and 

Regards,

Ed

 

________________________________________________________________________
________________________________________________________________________

Message: 2
Date: Thu, 11 Sep 2003 10:14:39 -0700

From: "masada wilmot" 
Subject: RE: OMni 2 Powersupply repair cont...

Hello all,



I'm a fairly new lurker on here but I feel the need to pipe in on this
thread. As I recall, the power supplies on the Omni are a simple standard
design with no exotic components. If the transformer is still OK, replacing
the active components would not cost more than $5 and you would not have to
install a mechanically different subsystem.



I've just repaired a Quadra supply that was just a standard
723/op-amp/TIP110-115 circuit. I haven't looked at the Omni for quite some
time but I expect that it is the same. Am I missing something here that went
before?



mw



PS, a supply that is capable of putting out more amps than you need is
normally not a problem. However, beware the supplies that require a minimum
load on one rail to maintain regulation - usually switchers.







-----Original Message-----
From: Ed Hallborg [mailto:ehallborg@...] 
Sent: Thursday, September 11, 2003 7:35 AM
To: vintagesynthrepair@yahoogroups.com
Subject: [vintagesynthrepair] OMni 2 Powersupply repair cont...



Robert,



Here's the only thing I found so far that meets your specs.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem
0> &item=2556349463&category=32720



Is this or something like it usable? I have done some google searches and
found the whole power supply boards but they seem like they are putting out
too many amps. I don't know if thats a problem or not---also the ones I
found on mouser.com are about 100$ apiece. That's fine if it will work.



Regards,

Ed

Message: 1
Date: Sat, 6 Sep 2003 08:36:27 -0700 (PDT)
From: Robert Benchic 
Subject: Re: Subject: Re: another broken omni 2

Ed, 

You would be replacing the entire power supply
eliminating the need to repair the regulator in the
original. The connections would be easy, positive and
negative 15 volts DC with a common ground and 115
volts AC. I can find you a supplier and appropriate
model if you like. 

-Bob


--- Ed Hallborg wrote:
> Thanks Robert,
> 
> Can you tell me anymore about these? I'm a bit
> confused as too whether they will take care of the
> -15 voltage regulator problem in the omni 2. Do
> they bypass the regulator or something. Is their a
> special procedure to hook them up?
> 
> Thanks,
> Ed
>
________________________________________________________________________




[This message contained attachments]



________________________________________________________________________
________________________________________________________________________



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Hi Ed, 

You most likely have a dead short on either the pos or
neg 15 volt bus. You can verify this with an ohmmeter.
Disconnect the supply and measure from each bus to
ground. If it's less than a few hundred ohms you have
a shorted bypass capacitor across the bus. Where the
PS voltage connects to each of the boards in the Omni
you will find a silver dipped tantalum capacitor from
each bus to ground. Change every one of them to an
electrolytic of the same value. As for the power
supply you can substitute the power transistors that
you can't cross with a different package. It's not
important to use an exact match. If you want to just
replace the entire supply Digi-Key has new linear
supplies for around $40. I can find you a suitable
replacement and get back to you with the part number. 

Good Luck, 
Bob



--- Ed Hallborg <ehallborg@...> wrote:
> 
> Thanks Massada  for  your input on this.  This has
> been an ongoing problem...I got this thing probably
> a year ago it looks great but gets no sound at all. 
> I did some checking on it, got the schematics and
> found that it appears to have a bad - 15 voltage
> regulator.  So I try and order the part, it has to
> cross to this and than cross to this and etc. 
> Finally I get a pair of regulators that should work,
> I put one in and it works momentarily and fails
> toasting a resistor on the way.  I take it to a
> local tech...They keep it two months and return it
> unrepaired, they cant find the -15 voltage regulator
> and suggest designing a new power supply for it -
> but don't seem eager to do it.  Mainly they tell me
> not to come back unless "I bring in something from
> after 1970".  So now I'm back where I started with
> the damn thing sitting in the corner of the studio
> collecting dust.  At this point I'm looking for
> anything and 
> 
> Regards,
> 
> Ed
> 
>  
> 
>
________________________________________________________________________
>
________________________________________________________________________
> 
> Message: 2
> Date: Thu, 11 Sep 2003 10:14:39 -0700
> From: "masada wilmot" 
> Subject: RE: OMni 2 Powersupply repair cont...
> 
> Hello all,
> 
> 
> 
> I'm a fairly new lurker on here but I feel the need
> to pipe in on this
> thread. As I recall, the power supplies on the Omni
> are a simple standard
> design with no exotic components. If the transformer
> is still OK, replacing
> the active components would not cost more than $5
> and you would not have to
> install a mechanically different subsystem.
> 
> 
> 
> I've just repaired a Quadra supply that was just a
> standard
> 723/op-amp/TIP110-115 circuit. I haven't looked at
> the Omni for quite some
> time but I expect that it is the same. Am I missing
> something here that went
> before?
> 
> 
> 
> mw
> 
> 
> 
> PS, a supply that is capable of putting out more
> amps than you need is
> normally not a problem. However, beware the supplies
> that require a minimum
> load on one rail to maintain regulation - usually
> switchers.
> 
> 
> 
> 
> 
> 
> 
> -----Original Message-----
> From: Ed Hallborg [mailto:ehallborg@...] 
> Sent: Thursday, September 11, 2003 7:35 AM
> To: vintagesynthrepair@yahoogroups.com
> Subject: [vintagesynthrepair] OMni 2 Powersupply
> repair cont...
> 
> 
> 
> Robert,
> 
> 
> 
> Here's the only thing I found so far that meets your
> specs.
> http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem
> 0> &item=2556349463&category=32720
> 
> 
> 
> Is this or something like it usable? I have done
> some google searches and
> found the whole power supply boards but they seem
> like they are putting out
> too many amps. I don't know if thats a problem or
> not---also the ones I
> found on mouser.com are about 100$ apiece. That's
> fine if it will work.
> 
> 
> 
> Regards,
> 
> Ed
> 
> Message: 1
> Date: Sat, 6 Sep 2003 08:36:27 -0700 (PDT)
> From: Robert Benchic 
> Subject: Re: Subject: Re: another broken omni 2
> 
> Ed, 
> 
> You would be replacing the entire power supply
> eliminating the need to repair the regulator in the
> original. The connections would be easy, positive
> and
> negative 15 volts DC with a common ground and 115
> volts AC. I can find you a supplier and appropriate
> model if you like. 
> 
> -Bob
> 
> 
> --- Ed Hallborg wrote:
> > Thanks Robert,
> > 
> > Can you tell me anymore about these? I'm a bit
> > confused as too whether they will take care of the
> > -15 voltage regulator problem in the omni 2. Do
> > they bypass the regulator or something. Is their a
> > special procedure to hook them up?
> > 
> > Thanks,
> > Ed
> >
>
________________________________________________________________________
> 
> 
> 
> 
> [This message contained attachments]
> 
> 
> 
>
________________________________________________________________________
>
________________________________________________________________________
> 
> 
> 
> Your use of Yahoo! Groups is subject to
> http://docs.yahoo.com/info/terms/ 
> 
> 
> 
> 
> 
> ---------------------------------
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> Yahoo! SiteBuilder - Free, easy-to-use web site
> design software


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Well I am certainly not impressed with your local tech! ARP's are (apart
from the sliders) some of the easiest vintage synths to fix. Just about all
of the parts are still easy to find. Even the top-octave divider in the Omni
can still be found.

 

Oberheims are probably a little easier since they generally socket all of
the IC's :-)

 

I've tried looking for the schematics on-line and the site where I found
them previously seems to be dead. Can you or someone e-mail me the power
supply schematic? I'll take a look and let you know if there are any issues
with parts. I'll try and give you a source for them as well. 

 

By the way, if the transformer is OK, an adequate power supply for this
beast could be designed and built by a half-competent tech in about an hour
and for less than $20 parts cost.

 

However, the most likely problem causing the power supply to fail is bad
tantalum decoupling caps on the other boards. This is a typical problem on
many pieces of electronics from this era. The timing caps on the voicing
boards can also fail and drag down the power supply. If we can get the power
supply working I can try and talk you through finding problems on the other
boards.

 

mw

-----Original Message-----
From: Ed Hallborg [mailto:] 
Sent: Friday, September 12, 2003 6:11 AM
To: vintagesynthrepair@yahoogroups.com
Subject: Re: [vintagesynthrepair] Digest Number 508

 

Thanks Massada  for  your input on this.  This has been an ongoing
problem...I got this thing probably a year ago it looks great but gets no
sound at all.  I did some checking on it, got the schematics and found that
it appears to have a bad - 15 voltage regulator.  So I try and order the
part, it has to cross to this and than cross to this and etc.  Finally I get
a pair of regulators that should work, I put one in and it works momentarily
and fails toasting a resistor on the way.  I take it to a local tech...They
keep it two months and return it unrepaired, they cant find the -15 voltage
regulator and suggest designing a new power supply for it - but don't seem
eager to do it.  Mainly they tell me not to come back unless "I bring in
something from after 1970".  So now I'm back where I started with the damn
thing sitting in the corner of the studio collecting dust.  At this point
I'm looking for anything and 

Regards,

Ed

 

________________________________________________________________________
________________________________________________________________________

Message: 2
Date: Thu, 11 Sep 2003 10:14:39 -0700
From: "masada wilmot" 
Subject: RE: OMni 2 Powersupply repair cont...

Hello all,



I'm a fairly new lurker on here but I feel the need to pipe in on this
thread. As I recall, the power supplies on the Omni are a simple standard
design with no exotic components. If the transformer is still OK, replacing
the active components would not cost more than $5 and you would not have to
install a mechanically different subsystem.



I've just repaired a Quadra supply that was just a standard
723/op-amp/TIP110-115 circuit. I haven't looked at the Omni for quite some
time but I expect that it is the same. Am I missing something here that went
before?



mw



PS, a supply that is capable of putting out more amps than you need is
normally not a problem. However, beware the supplies that require a minimum
load on one rail to maintain regulation - usually switchers.







-----Original Message-----
From: Ed Hallborg [mailto:ehallborg@...] 
Sent: Thursday, September 11, 2003 7:35 AM
To: vintagesynthrepair@yahoogroups.com
Subject: [vintagesynthrepair] OMni 2 Powersupply repair cont...



Robert,



Here's the only thing I found so far that meets your specs.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem
0> &item=2556349463&category=32720



Is this or something like it usable? I have done some google searches and
found the whole power supply boards but they seem like they are putting out
too many amps. I don't know if thats a problem or not---also the ones I
found on mouser.com are about 100$ apiece. That's fine if it will work.



Regards,

Ed

Message: 1
Date: Sat, 6 Sep 2003 08:36:27 -0700 (PDT)
From: Robert Benchic 
Subject: Re: Subject: Re: another broken omni 2

Ed, 

You would be replacing the entire power supply
eliminating the need to repair the regulator in the
original. The connections would be easy, positive and
negative 15 volts DC with a common ground and 115
volts AC. I can find you a supplier and appropriate
model if you like. 

-Bob


--- Ed Hallborg wrote:
> Thanks Robert,
> 
> Can you tell me anymore about these? I'm a bit
> confused as too whether they will take care of the
> -15 voltage regulator problem in the omni 2. Do
> they bypass the regulator or something. Is their a
> special procedure to hook them up?
> 
> Thanks,
> Ed
>
________________________________________________________________________




[This message contained attachments]



________________________________________________________________________
________________________________________________________________________



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Ed, Digi-Key Electronics http://www.digikey.com has a
Power-One dual 15 volt 400ma linear power supply, part
# 179-2065-ND for $40.54 

--- Robert Benchic <bobb1956@...> wrote:
> Hi Ed, 
> 
> You most likely have a dead short on either the pos
> or
> neg 15 volt bus. You can verify this with an
> ohmmeter.
> Disconnect the supply and measure from each bus to
> ground. If it's less than a few hundred ohms you
> have
> a shorted bypass capacitor across the bus. Where the
> PS voltage connects to each of the boards in the
> Omni
> you will find a silver dipped tantalum capacitor
> from
> each bus to ground. Change every one of them to an
> electrolytic of the same value. As for the power
> supply you can substitute the power transistors that
> you can't cross with a different package. It's not
> important to use an exact match. If you want to just
> replace the entire supply Digi-Key has new linear
> supplies for around $40. I can find you a suitable
> replacement and get back to you with the part
> number. 
> 
> Good Luck, 
> Bob
> 
> 
> 
> --- Ed Hallborg <ehallborg@...> wrote:
> > 
> > Thanks Massada  for  your input on this.  This has
> > been an ongoing problem...I got this thing
> probably
> > a year ago it looks great but gets no sound at
> all. 
> > I did some checking on it, got the schematics and
> > found that it appears to have a bad - 15 voltage
> > regulator.  So I try and order the part, it has to
> > cross to this and than cross to this and etc. 
> > Finally I get a pair of regulators that should
> work,
> > I put one in and it works momentarily and fails
> > toasting a resistor on the way.  I take it to a
> > local tech...They keep it two months and return it
> > unrepaired, they cant find the -15 voltage
> regulator
> > and suggest designing a new power supply for it -
> > but don't seem eager to do it.  Mainly they tell
> me
> > not to come back unless "I bring in something from
> > after 1970".  So now I'm back where I started with
> > the damn thing sitting in the corner of the studio
> > collecting dust.  At this point I'm looking for
> > anything and 
> > 
> > Regards,
> > 
> > Ed
> > 
> >  
> > 
> >
>
________________________________________________________________________
> >
>
________________________________________________________________________
> > 
> > Message: 2
> > Date: Thu, 11 Sep 2003 10:14:39 -0700
> > From: "masada wilmot" 
> > Subject: RE: OMni 2 Powersupply repair cont...
> > 
> > Hello all,
> > 
> > 
> > 
> > I'm a fairly new lurker on here but I feel the
> need
> > to pipe in on this
> > thread. As I recall, the power supplies on the
> Omni
> > are a simple standard
> > design with no exotic components. If the
> transformer
> > is still OK, replacing
> > the active components would not cost more than $5
> > and you would not have to
> > install a mechanically different subsystem.
> > 
> > 
> > 
> > I've just repaired a Quadra supply that was just a
> > standard
> > 723/op-amp/TIP110-115 circuit. I haven't looked at
> > the Omni for quite some
> > time but I expect that it is the same. Am I
> missing
> > something here that went
> > before?
> > 
> > 
> > 
> > mw
> > 
> > 
> > 
> > PS, a supply that is capable of putting out more
> > amps than you need is
> > normally not a problem. However, beware the
> supplies
> > that require a minimum
> > load on one rail to maintain regulation - usually
> > switchers.
> > 
> > 
> > 
> > 
> > 
> > 
> > 
> > -----Original Message-----
> > From: Ed Hallborg [mailto:ehallborg@...] 
> > Sent: Thursday, September 11, 2003 7:35 AM
> > To: vintagesynthrepair@yahoogroups.com
> > Subject: [vintagesynthrepair] OMni 2 Powersupply
> > repair cont...
> > 
> > 
> > 
> > Robert,
> > 
> > 
> > 
> > Here's the only thing I found so far that meets
> your
> > specs.
> > http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem
> > 0> &item=2556349463&category=32720
> > 
> > 
> > 
> > Is this or something like it usable? I have done
> > some google searches and
> > found the whole power supply boards but they seem
> > like they are putting out
> > too many amps. I don't know if thats a problem or
> > not---also the ones I
> > found on mouser.com are about 100$ apiece. That's
> > fine if it will work.
> > 
> > 
> > 
> > Regards,
> > 
> > Ed
> > 
> > Message: 1
> > Date: Sat, 6 Sep 2003 08:36:27 -0700 (PDT)
> > From: Robert Benchic 
> > Subject: Re: Subject: Re: another broken omni 2
> > 
> > Ed, 
> > 
> > You would be replacing the entire power supply
> > eliminating the need to repair the regulator in
> the
> > original. The connections would be easy, positive
> > and
> > negative 15 volts DC with a common ground and 115
> > volts AC. I can find you a supplier and
> appropriate
> > model if you like. 
> > 
> > -Bob
> > 
> > 
> > --- Ed Hallborg wrote:
> > > Thanks Robert,
> > > 
> > > Can you tell me anymore about these? I'm a bit
> > > confused as too whether they will take care of
> the
> > > -15 voltage regulator problem in the omni 2. Do
> > > they bypass the regulator or something. Is their
> a
> > > special procedure to hook them up?
> > > 
> > > Thanks,
> > > Ed
> > >
> >
>
________________________________________________________________________
> > 
> > 
> > 
> > 
> > [This message contained attachments]
> > 
> > 
> > 
> >
> 
=== message truncated ===


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On Fri, 12 Sep 2003, masada wilmot wrote:

> I've tried looking for the schematics on-line and the site where I found
> them previously seems to be dead. Can you or someone e-mail me the power
> supply schematic? I'll take a look and let you know if there are any issues
> with parts. I'll try and give you a source for them as well. 

masada, 

sorry about the omni site goin' down (it went down along w/my job )-:

for the time being, here are links to the assembly drawing & schematics 
for the omni power supply

http://www.cs.umass.edu/~pbrown/images/ps-assy.jpg
http://www.cs.umass.edu/~pbrown/images/ps-schematic.jpg

also, i have attached the parts list for the power supply from the manual 
(unfortunately, it doesn't list all parts)

hope this helps...

regards, PB>>

=====
PC BOARD, "POWER SUPPLY"

REFERENCE              ARP PART NUMBER  ARP/MFG NUMBER    DESCRIPTION
================================================================================
CR1,2,3,4,5                 1200201     1N4001            RECT, 50V, 1A
Q3                          1303001     2N3906            TSTR, PNP, GP
Zl                          1401301     723DC             IC, VOLTAGE REGULATOR
Z2                          1400801     LM30lAN           IC, OP AMPL
R7,8                        1000111     BW-20             RES, WW, TC, 0.68 OHM, 1W, 5%
R19,20                      1000915     U201R104B         POT, ROTARY TRIM, 100K, 1/4 W, 30%
C8                          1100609     G-0-001-G-20-0    CAP, TANT, 1UF, 35V, 20%
C6,7                        1100612     G-0-010-G-20-0    CAP, TANT, 10UF, 35V, 20%
C3                          1101702     TAD250TQ50        CAP, ELECT, 250UF, 50V, +50-10%
Cl,2                        1101301     TCW102V050N1R3P   CAP, ELECT, 1000UF, 50V, +75-10%
Q1                          1304501     MJE1100           TSTR, NPN, PAR DARL
Q2                          1304301     MJE1090           TSTR, PNP, PWR DARL
T1                          5704401                       TRANSFORMER, POWER
F1                          1700404     MDV-1/2           FUSE, PIGTAIL, SLO-BLO 1/2A 250V

Pete, 

 

Many thanks for the schematics and sorry to hear about the job (there's a
lot of it about). Are the other Omni files still on that server somewhere? I
would like to get a hold of them. I'm still kicking myself for not
downloading them when I first found your page. I thought "Hey, it's not
going to go away is it..?" Famous last words.

 

And many more thanks to all who post schematics and service info for the old
beasts. We appreciate it.

 

mw

-----Original Message-----
From: Peter Brown [mailto:pbrown@cs.umass.edu] 
Sent: Friday, September 12, 2003 8:08 PM
To: vintagesynthrepair@yahoogroups.com
Subject: RE: [vintagesynthrepair] OMNI 2 power supply

 

On Fri, 12 Sep 2003, masada wilmot wrote:

> I've tried looking for the schematics on-line and the site where I found
> them previously seems to be dead. Can you or someone e-mail me the power
> supply schematic? I'll take a look and let you know if there are any
issues
> with parts. I'll try and give you a source for them as well. 

masada, 

sorry about the omni site goin' down (it went down along w/my job )-:

for the time being, here are links to the assembly drawing & schematics 
for the omni power supply

http://www.cs.umass.edu/~pbrown/images/ps-assy.jpg
http://www.cs.umass.edu/~pbrown/images/ps-schematic.jpg

also, i have attached the parts list for the power supply from the manual 
(unfortunately, it doesn't list all parts)

hope this helps...

regards, PB>>

=====
PC BOARD, "POWER SUPPLY"

REFERENCE              ARP PART NUMBER  ARP/MFG NUMBER    DESCRIPTION
============================================================================
====
CR1,2,3,4,5                 1200201     1N4001            RECT, 50V, 1A
Q3                          1303001     2N3906            TSTR, PNP, GP
Zl                          1401301     723DC             IC, VOLTAGE
REGULATOR
Z2                          1400801     LM30lAN           IC, OP AMPL
R7,8                        1000111     BW-20             RES, WW, TC, 0.68
OHM, 1W, 5%
R19,20                      1000915     U201R104B         POT, ROTARY TRIM,
100K, 1/4 W, 30%
C8                          1100609     G-0-001-G-20-0    CAP, TANT, 1UF,
35V, 20%
C6,7                        1100612     G-0-010-G-20-0    CAP, TANT, 10UF,
35V, 20%
C3                          1101702     TAD250TQ50        CAP, ELECT, 250UF,
50V, +50-10%
Cl,2                        1101301     TCW102V050N1R3P   CAP, ELECT,
1000UF, 50V, +75-10%
Q1                          1304501     MJE1100           TSTR, NPN, PAR
DARL
Q2                          1304301     MJE1090           TSTR, PNP, PWR
DARL
T1                          5704401                       TRANSFORMER, POWER
F1                          1700404     MDV-1/2           FUSE, PIGTAIL,
SLO-BLO 1/2A 250V







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hi Masada,

i hope to have the omni site back up (on a different server) soon...in the
meantime, let me know if you need anything specific & i can put it up for
download

thanks, PB>>

On Fri, 12 Sep 2003, masada wilmot wrote:

> Pete, 
> 
>  
> 
> Many thanks for the schematics and sorry to hear about the job (there's a
> lot of it about). Are the other Omni files still on that server somewhere? I
> would like to get a hold of them. I'm still kicking myself for not
> downloading them when I first found your page. I thought "Hey, it's not
> going to go away is it..?" Famous last words.
> 
>  
> 
> And many more thanks to all who post schematics and service info for the old
> beasts. We appreciate it.
> 
>  
> 
> mw
> 
>  
> 
> -----Original Message-----
> From: Peter Brown [mailto:pbrown@...] 
> Sent: Friday, September 12, 2003 8:08 PM
> To: vintagesynthrepair@yahoogroups.com
> Subject: RE: [vintagesynthrepair] OMNI 2 power supply
> 
>  
> 
> On Fri, 12 Sep 2003, masada wilmot wrote:
> 
> > I've tried looking for the schematics on-line and the site where I found
> > them previously seems to be dead. Can you or someone e-mail me the power
> > supply schematic? I'll take a look and let you know if there are any
> issues
> > with parts. I'll try and give you a source for them as well. 
> 
> masada, 
> 
> sorry about the omni site goin' down (it went down along w/my job )-:
> 
> for the time being, here are links to the assembly drawing & schematics 
> for the omni power supply
> 
> http://www.cs.umass.edu/~pbrown/images/ps-assy.jpg
> http://www.cs.umass.edu/~pbrown/images/ps-schematic.jpg
> 
> also, i have attached the parts list for the power supply from the manual 
> (unfortunately, it doesn't list all parts)
> 
> hope this helps...
> 
> regards, PB>>
> 
> =====
> PC BOARD, "POWER SUPPLY"
> 
> REFERENCE              ARP PART NUMBER  ARP/MFG NUMBER    DESCRIPTION
> ============================================================================
> ====
> CR1,2,3,4,5                 1200201     1N4001            RECT, 50V, 1A
> Q3                          1303001     2N3906            TSTR, PNP, GP
> Zl                          1401301     723DC             IC, VOLTAGE
> REGULATOR
> Z2                          1400801     LM30lAN           IC, OP AMPL
> R7,8                        1000111     BW-20             RES, WW, TC, 0.68
> OHM, 1W, 5%
> R19,20                      1000915     U201R104B         POT, ROTARY TRIM,
> 100K, 1/4 W, 30%
> C8                          1100609     G-0-001-G-20-0    CAP, TANT, 1UF,
> 35V, 20%
> C6,7                        1100612     G-0-010-G-20-0    CAP, TANT, 10UF,
> 35V, 20%
> C3                          1101702     TAD250TQ50        CAP, ELECT, 250UF,
> 50V, +50-10%
> Cl,2                        1101301     TCW102V050N1R3P   CAP, ELECT,
> 1000UF, 50V, +75-10%
> Q1                          1304501     MJE1100           TSTR, NPN, PAR
> DARL
> Q2                          1304301     MJE1090           TSTR, PNP, PWR
> DARL
> T1                          5704401                       TRANSFORMER, POWER
> F1                          1700404     MDV-1/2           FUSE, PIGTAIL,
> SLO-BLO 1/2A 250V
> 
> 
> 
> 
> 
> 
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-- 
Peter Brown, Ph.D.          Senior Software Engineer
Dept. of Computer Science        140 Governors Drive 
University of Massachusetts   Amherst, MA 01003-4610
Phone: (413) 577-2505            Fax: (413) 545-1249
pbrown@...  http://www.cs.umass.edu/~pbrown