Empathy List Archives

DM

Dave M

Mon, Apr 23, 2012 7:40 PM

From: "Marvin E. Gozum" marvin.gozum@jefferson.edu
Hello all good folks:

A little bit off topic, but this defunct company with a heyday from ~
1950s-1980s made very good bench linear PSU, including a line called
'precision power supplies', something more labeled precision voltage
sources today. However, the precision series was capable of 0.5-4A
output.

A user could dial a VDC set precisely to uV levels on most voltage
ranges, and could hold its dial setting to single digit uV for ~ >= 8
hours, but to 100uVs over a month.

I'm interested in anyone who can give their impression of the history
of this company, their experience with their products, or have
advertisements or scans of their catalog of equipment during their
prime.

I used to repair and calibrate lots of Power Designs supplies back in the
late 60s and early 70s. They were always top-notch supplies, very low noise
& ripple, and seldom failed.
For instance, the ripple/noise spec for the model 5015 was < 250uV RMS. amd
stability was 0.01% +5mV per 8 hours.
The model 2020 precision supply ripple/noise was 100uV P-P, and stability
was 0.001% + 100uV per 8 hours. Very nice supplies.
I have several of the PDI supplies in my shop, and use them often. They are
excellent supplies. I love the constant current mode on them; that feature
has saved more than one project from going up in flames.
I have a model C500 (0-100V/0.5V precision supply) that needs repair. The
reference assy is bad; haven't had time to get into it.
If you need manuals, I have PDF copies of a few models, (mainly models that
I have in my shop). Post your interests and if I have the manual, I'll send
it to you.

Dave M
A woman has the last word in any argument. Anything a man says after that is
the beginning of a new argument.

> From: "Marvin E. Gozum" <marvin.gozum@jefferson.edu> > Hello all good folks: > > A little bit off topic, but this defunct company with a heyday from ~ > 1950s-1980s made very good bench linear PSU, including a line called > 'precision power supplies', something more labeled precision voltage > sources today. However, the precision series was capable of 0.5-4A > output. > > A user could dial a VDC set precisely to uV levels on most voltage > ranges, and could hold its dial setting to single digit uV for ~ >= 8 > hours, but to 100uVs over a month. > > I'm interested in anyone who can give their impression of the history > of this company, their experience with their products, or have > advertisements or scans of their catalog of equipment during their > prime. > > I used to repair and calibrate lots of Power Designs supplies back in the late 60s and early 70s. They were always top-notch supplies, very low noise & ripple, and seldom failed. For instance, the ripple/noise spec for the model 5015 was < 250uV RMS. amd stability was 0.01% +5mV per 8 hours. The model 2020 precision supply ripple/noise was 100uV P-P, and stability was 0.001% + 100uV per 8 hours. Very nice supplies. I have several of the PDI supplies in my shop, and use them often. They are excellent supplies. I love the constant current mode on them; that feature has saved more than one project from going up in flames. I have a model C500 (0-100V/0.5V precision supply) that needs repair. The reference assy is bad; haven't had time to get into it. If you need manuals, I have PDF copies of a few models, (mainly models that I have in my shop). Post your interests and if I have the manual, I'll send it to you. Dave M A woman has the last word in any argument. Anything a man says after that is the beginning of a new argument.

ME

Marvin E. Gozum

Wed, Apr 25, 2012 1:55 PM

This is fantastic news, glad to meet you here. You knew them at
their prime, when they were like new! While CC is standard in many of
today's supplies, its hard to find modern ones at this cost that
match the PD Precision regulation.

The stability is impressive even today, and moreso, the Precision
series have their key regulation components all transistors.

Since you mention repair, were some less durable than others? I can
see calibrating per your protocol as needed.

I looked up the transistors in the 2020B and 5020 and half of them
are unobtanium. By chance, does anyone have the specs of
these? I've tried the web based resources and located 2 transistor
specs, and were barely readable.

Transistors:
FS1700E
2N2219A
IR4230
TI0421
FS2270B
MS1700G
FS1075
2N5416

Does anyone know what these voltage references where?

Voltage References
A65555-1
A65555-2
A65555-3

At 03:40 PM 4/23/2012, Dave M wrote:

I used to repair and calibrate lots of Power Designs supplies back
in the late 60s and early 70s. They were always top-notch supplies,
very low noise & ripple, and seldom failed.
For instance, the ripple/noise spec for the model 5015 was < 250uV
RMS. amd stability was 0.01% +5mV per 8 hours.
The model 2020 precision supply ripple/noise was 100uV P-P, and
stability was 0.001% + 100uV per 8 hours. Very nice supplies.
I have several of the PDI supplies in my shop, and use them
often. They are excellent supplies. I love the constant current
mode on them; that feature has saved more than one project from
going up in flames.
I have a model C500 (0-100V/0.5V precision supply) that needs
repair. The reference assy is bad; haven't had time to get into it.
If you need manuals, I have PDF copies of a few models, (mainly
models that I have in my shop). Post your interests and if I have
the manual, I'll send it to you.

Dave M
A woman has the last word in any argument. Anything a man says after
that is the beginning of a new argument.

volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.

Sincerely,

Marv Gozum
Philadelphia, PA

This is fantastic news, glad to meet you here. You knew them at their prime, when they were like new! While CC is standard in many of today's supplies, its hard to find modern ones at this cost that match the PD Precision regulation. The stability is impressive even today, and moreso, the Precision series have their key regulation components all transistors. Since you mention repair, were some less durable than others? I can see calibrating per your protocol as needed. I looked up the transistors in the 2020B and 5020 and half of them are unobtanium. By chance, does anyone have the specs of these? I've tried the web based resources and located 2 transistor specs, and were barely readable. Transistors: FS1700E 2N2219A IR4230 TI0421 FS2270B MS1700G FS1075 2N5416 Does anyone know what these voltage references where? Voltage References A65555-1 A65555-2 A65555-3 At 03:40 PM 4/23/2012, Dave M wrote: >I used to repair and calibrate lots of Power Designs supplies back >in the late 60s and early 70s. They were always top-notch supplies, >very low noise & ripple, and seldom failed. >For instance, the ripple/noise spec for the model 5015 was < 250uV >RMS. amd stability was 0.01% +5mV per 8 hours. >The model 2020 precision supply ripple/noise was 100uV P-P, and >stability was 0.001% + 100uV per 8 hours. Very nice supplies. >I have several of the PDI supplies in my shop, and use them >often. They are excellent supplies. I love the constant current >mode on them; that feature has saved more than one project from >going up in flames. >I have a model C500 (0-100V/0.5V precision supply) that needs >repair. The reference assy is bad; haven't had time to get into it. >If you need manuals, I have PDF copies of a few models, (mainly >models that I have in my shop). Post your interests and if I have >the manual, I'll send it to you. > >Dave M >A woman has the last word in any argument. Anything a man says after >that is the beginning of a new argument. > > >_______________________________________________ >volt-nuts mailing list -- volt-nuts@febo.com >To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >and follow the instructions there. Sincerely, Marv Gozum Philadelphia, PA

AJ

Andreas Jahn

Wed, Apr 25, 2012 10:04 PM

At least the 2N-Types can be found:

http://www.findchips.com/avail?part=2n2219a
http://www.findchips.com/avail?part=2n5416

For the rest: did you really read the type number or something like the
datecode (TI0421)

With best regards

Andreas

I looked up the transistors in the 2020B and 5020 and half of them are
unobtanium. By chance, does anyone have the specs of these? I've tried
the web based resources and located 2 transistor specs, and were barely
readable.

Transistors:
FS1700E
2N2219A
IR4230
TI0421
FS2270B
MS1700G
FS1075
2N5416

Does anyone know what these voltage references where?

Voltage References
A65555-1
A65555-2
A65555-3

At 03:40 PM 4/23/2012, Dave M wrote:

I used to repair and calibrate lots of Power Designs supplies back in the
late 60s and early 70s. They were always top-notch supplies, very low
noise & ripple, and seldom failed.
For instance, the ripple/noise spec for the model 5015 was < 250uV RMS.
amd stability was 0.01% +5mV per 8 hours.
The model 2020 precision supply ripple/noise was 100uV P-P, and stability
was 0.001% + 100uV per 8 hours. Very nice supplies.
I have several of the PDI supplies in my shop, and use them often. They
are excellent supplies. I love the constant current mode on them; that
feature has saved more than one project from going up in flames.
I have a model C500 (0-100V/0.5V precision supply) that needs repair. The
reference assy is bad; haven't had time to get into it.
If you need manuals, I have PDF copies of a few models, (mainly models
that I have in my shop). Post your interests and if I have the manual,
I'll send it to you.

Dave M
A woman has the last word in any argument. Anything a man says after that
is the beginning of a newargument.

volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.

Sincerely,

Marv Gozum
Philadelphia, PA

volt-nuts mailing list -- volt-nuts@febo.com
To unsubscribe, go to
https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts
and follow the instructions there.

At least the 2N-Types can be found: http://www.findchips.com/avail?part=2n2219a http://www.findchips.com/avail?part=2n5416 For the rest: did you really read the type number or something like the datecode (TI0421) With best regards Andreas > I looked up the transistors in the 2020B and 5020 and half of them are > unobtanium. By chance, does anyone have the specs of these? I've tried > the web based resources and located 2 transistor specs, and were barely > readable. > > > Transistors: > FS1700E > 2N2219A > IR4230 > TI0421 > FS2270B > MS1700G > FS1075 > 2N5416 > > Does anyone know what these voltage references where? > > Voltage References > A65555-1 > A65555-2 > A65555-3 > > > > > At 03:40 PM 4/23/2012, Dave M wrote: > >>I used to repair and calibrate lots of Power Designs supplies back in the >>late 60s and early 70s. They were always top-notch supplies, very low >>noise & ripple, and seldom failed. >>For instance, the ripple/noise spec for the model 5015 was < 250uV RMS. >>amd stability was 0.01% +5mV per 8 hours. >>The model 2020 precision supply ripple/noise was 100uV P-P, and stability >>was 0.001% + 100uV per 8 hours. Very nice supplies. >>I have several of the PDI supplies in my shop, and use them often. They >>are excellent supplies. I love the constant current mode on them; that >>feature has saved more than one project from going up in flames. >>I have a model C500 (0-100V/0.5V precision supply) that needs repair. The >>reference assy is bad; haven't had time to get into it. >>If you need manuals, I have PDF copies of a few models, (mainly models >>that I have in my shop). Post your interests and if I have the manual, >>I'll send it to you. >> >>Dave M >>A woman has the last word in any argument. Anything a man says after that >>is the beginning of a newargument. >> >> >>_______________________________________________ >>volt-nuts mailing list -- volt-nuts@febo.com >>To unsubscribe, go to >>https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts >>and follow the instructions there. > > > > Sincerely, > > > > Marv Gozum > Philadelphia, PA > > > _______________________________________________ > volt-nuts mailing list -- volt-nuts@febo.com > To unsubscribe, go to > https://www.febo.com/cgi-bin/mailman/listinfo/volt-nuts > and follow the instructions there.

ME

Marvin E. Gozum

Thu, Apr 26, 2012 12:56 PM

Thank you Andreas, for the effort. Yes, I located the 2N types
online too. That list of key parts is from the service manual, p.14.

https://docs.google.com/viewer?a=v&q=cache:EwpcBMGQ5TAJ:128.238.9.201/~kurt/manuals/manuals/Other/POWER%2520DESIGNS%25202020B,%25205020,%2520C500%2520Instruction.pdf+&hl=en&gl=us&pid=bl&srcid=ADGEESgOKHKiERW-JexT4B1lKdgXdxFrlR3FKBaAISArSRNrlmm-L65VRQh2WZMvUBY3QvNaKRhZXi3nvdJuMMzLNhgGF1Zjzdz0wmT83-bRw-oCoH3jyU819g4ik3Z5_13PKKNwF4RS&sig=AHIEtbT9w8oh_e9PK_kT7JD8rqPC1kPWRA

The google copy is sourced from ko4bb's manual archive page, in the
non-indexed section. It could have been moved, follow main link:

http://www.ko4bb.com/manuals/

At 06:04 PM 4/25/2012, Andreas Jahn wrote:

At least the 2N-Types can be found:

http://www.findchips.com/avail?part=2n2219a
http://www.findchips.com/avail?part=2n5416

For the rest: did you really read the type number or something like
the datecode (TI0421)

With best regards

Andreas

I looked up the transistors in the 2020B and 5020 and half of them
are unobtanium. By chance, does anyone have the specs of
these? I've tried the web based resources and located 2 transistor
specs, and were barely readable.

Transistors:
FS1700E
2N2219A
IR4230
TI0421
FS2270B
MS1700G
FS1075
2N5416

Does anyone know what these voltage references where?

Voltage References
A65555-1
A65555-2
A65555-3

Sincerely,

Marv Gozum
Philadelphia, PA

Thank you Andreas, for the effort. Yes, I located the 2N types online too. That list of key parts is from the service manual, p.14. https://docs.google.com/viewer?a=v&q=cache:EwpcBMGQ5TAJ:128.238.9.201/~kurt/manuals/manuals/Other/POWER%2520DESIGNS%25202020B,%25205020,%2520C500%2520Instruction.pdf+&hl=en&gl=us&pid=bl&srcid=ADGEESgOKHKiERW-JexT4B1lKdgXdxFrlR3FKBaAISArSRNrlmm-L65VRQh2WZMvUBY3QvNaKRhZXi3nvdJuMMzLNhgGF1Zjzdz0wmT83-bRw-oCoH3jyU819g4ik3Z5_13PKKNwF4RS&sig=AHIEtbT9w8oh_e9PK_kT7JD8rqPC1kPWRA The google copy is sourced from ko4bb's manual archive page, in the non-indexed section. It could have been moved, follow main link: http://www.ko4bb.com/manuals/ At 06:04 PM 4/25/2012, Andreas Jahn wrote: >At least the 2N-Types can be found: > >http://www.findchips.com/avail?part=2n2219a >http://www.findchips.com/avail?part=2n5416 > >For the rest: did you really read the type number or something like >the datecode (TI0421) > >With best regards > >Andreas > >>I looked up the transistors in the 2020B and 5020 and half of them >>are unobtanium. By chance, does anyone have the specs of >>these? I've tried the web based resources and located 2 transistor >>specs, and were barely readable. >> >> >>Transistors: >>FS1700E >>2N2219A >>IR4230 >>TI0421 >>FS2270B >>MS1700G >>FS1075 >>2N5416 >> >>Does anyone know what these voltage references where? >> >>Voltage References >>A65555-1 >>A65555-2 >>A65555-3 >> Sincerely, Marv Gozum Philadelphia, PA

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Re: [volt-nuts] Power Designs Precision Power Supplies