I'm going through some stuff I have to move (retiring in June) and trying to decide what to keep. I have a Burr Brown 501 dual supply that puts out +/-15 volts with 115 VAC in. The supply is working but I don't know what's its use was originally. It's a compact block and it's heavy, but there's no current rating listed and I haven't been able to find out anything about it. Is it supposed to supply a reference for calibrating meters or is it used as a power supply? Not being adjustable I wonder if it's made for something specific. Any insight appreciated.

On Thu, 1 Feb 2024 11:14:13 -0800 (PST), "ohg...@gmail.com"
<ohger1s@gmail.com> wrote:

>I'm going through some stuff I have to move (retiring in June) and trying to decide what to keep. I have a Burr Brown 501 dual supply that puts out +/-15 volts with 115 VAC in. The supply is working but I don't know what's its use was originally. It's a compact block and it's heavy, but there's no current rating listed and I haven't been able to find out anything about it. Is it supposed to supply a reference for calibrating meters or is it used as a power supply? Not being adjustable I wonder if it's made for something specific. Any insight appreciated.

It's just a supply aimed at permanent installation
in analog circuits.

If it's got air holes, (or you can crack the case)
you might see an internal preset pot or two -
one to adjust output (11-16V)
and one for balance -
sometimes a current limit adjustment.

It might have some value as an antique.

RL

On Friday, February 2, 2024 at 10:22:49 AM UTC-5, legg wrote:
> On Thu, 1 Feb 2024 11:14:13 -0800 (PST), "ohg...@gmail.com"
> <ohg...@gmail.com> wrote:
>
> >I'm going through some stuff I have to move (retiring in June) and trying to decide what to keep. I have a Burr Brown 501 dual supply that puts out +/-15 volts with 115 VAC in. The supply is working but I don't know what's its use was originally. It's a compact block and it's heavy, but there's no current rating listed and I haven't been able to find out anything about it. Is it supposed to supply a reference for calibrating meters or is it used as a power supply? Not being adjustable I wonder if it's made for something specific. Any insight appreciated.
> It's just a supply aimed at permanent installation
> in analog circuits.
>
> If it's got air holes, (or you can crack the case)
> you might see an internal preset pot or two -
> one to adjust output (11-16V)
> and one for balance -
> sometimes a current limit adjustment.
>
> It might have some value as an antique.
>
> RL

No ventilation of any kind - just small and heavy - which is why I thought it might be used for a micro current reference source. It is pretty tightly regulated even with no load other than the meter as it reads 15.01 (Fluke 177) and doesn't change from 100 to 150 VAC.

I guess I can put a one amp load on it and see if it gets hot or fails...

Thanks for the reply.

On Thursday, February 1, 2024 at 2:14:17 PM UTC-5, ohg...@gmail.com wrote:
> I'm going through some stuff I have to move (retiring in June) and trying to decide what to keep. I have a Burr Brown 501 dual supply that puts out +/-15 volts with 115 VAC in. The supply is working but I don't know what's its use was originally. It's a compact block and it's heavy, but there's no current rating listed and I haven't been able to find out anything about it. Is it supposed to supply a reference for calibrating meters or is it used as a power supply? Not being adjustable I wonder if it's made for something specific. Any insight appreciated.

I believe it was just used as a power supply. Some years ago I got some interface hardware that was associated with a PDP8. Inside the hardware box was a card with BB 501. I liberated the 501 and used it in my poor mans triple mode PS, alongside my 5VDC open frame PS. I disconnected the interface box from the PDP8 and got it running without any issues.

On Fri, 2 Feb 2024 08:10:46 -0800 (PST), "ohg...@gmail.com"
<ohger1s@gmail.com> wrote:

>On Friday, February 2, 2024 at 10:22:49?AM UTC-5, legg wrote:
>> On Thu, 1 Feb 2024 11:14:13 -0800 (PST), "ohg...@gmail.com"
>> <ohg...@gmail.com> wrote:
>>
>> >I'm going through some stuff I have to move (retiring in June) and trying to decide what to keep. I have a Burr Brown 501 dual supply that puts out +/-15 volts with 115 VAC in. The supply is working but I don't know what's its use was originally. It's a compact block and it's heavy, but there's no current rating listed and I haven't been able to find out anything about it. Is it supposed to supply a reference for calibrating meters or is it used as a power supply? Not being adjustable I wonder if it's made for something specific. Any insight appreciated.
>> It's just a supply aimed at permanent installation
>> in analog circuits.
>>
>> If it's got air holes, (or you can crack the case)
>> you might see an internal preset pot or two -
>> one to adjust output (11-16V)
>> and one for balance -
>> sometimes a current limit adjustment.
>>
>> It might have some value as an antique.
>>
>> RL
>
>No ventilation of any kind - just small and heavy - which is why I thought it might be used for a micro current reference source. It is pretty tightly regulated even with no load other than the meter as it reads 15.01 (Fluke 177) and doesn't change from 100 to 150 VAC.
>
>I guess I can put a one amp load on it and see if it gets hot or fails...
>
>Thanks for the reply.
>

I think you'll find it's both low drift and quiet, but
it's getting past it's due date w/r to low frequency
electrolytic filter caps . . . and even film caps.

The casing should keep any 60Hz flux from contaminating
your local measurements.

Built for instrumentation.

I suggested antique value after spotting one on ebay
for $$$.

RL

On Friday, February 2, 2024 at 1:38:38 PM UTC-5, legg wrote:
> On Fri, 2 Feb 2024 08:10:46 -0800 (PST), "ohg...@gmail.com"
> <ohg...@gmail.com> wrote:
> >On Friday, February 2, 2024 at 10:22:49?AM UTC-5, legg wrote:
> >> On Thu, 1 Feb 2024 11:14:13 -0800 (PST), "ohg...@gmail.com"
> >> <ohg...@gmail.com> wrote:
> >>
> >> >I'm going through some stuff I have to move (retiring in June) and trying to decide what to keep. I have a Burr Brown 501 dual supply that puts out +/-15 volts with 115 VAC in. The supply is working but I don't know what's its use was originally. It's a compact block and it's heavy, but there's no current rating listed and I haven't been able to find out anything about it. Is it supposed to supply a reference for calibrating meters or is it used as a power supply? Not being adjustable I wonder if it's made for something specific. Any insight appreciated.
> >> It's just a supply aimed at permanent installation
> >> in analog circuits.
> >>

> I think you'll find it's both low drift and quiet, but
> it's getting past it's due date w/r to low frequency
> electrolytic filter caps . . . and even film caps.
>

<<< Given that it's sealed, I figured it's all film caps (although I certainly am not sure), but good quality film caps have never had an expiration date in the ones I've run across the last 50 years or so.

> I suggested antique value after spotting one on ebay
> for $$$.

Yeah, I saw that LOL, but as I always said when comes to ebay - "askin' ain't the same as gettin'"

It's small enough where it won't be a burden to store it for a while, so I'll not pitch it out yet.

On Sat, 3 Feb 2024 09:28:19 -0800 (PST), "ohg...@gmail.com"
<ohger1s@gmail.com> wrote:

>On Friday, February 2, 2024 at 1:38:38?PM UTC-5, legg wrote:
>> On Fri, 2 Feb 2024 08:10:46 -0800 (PST), "ohg...@gmail.com"
>> <ohg...@gmail.com> wrote:
>> >On Friday, February 2, 2024 at 10:22:49?AM UTC-5, legg wrote:
>> >> On Thu, 1 Feb 2024 11:14:13 -0800 (PST), "ohg...@gmail.com"
>> >> <ohg...@gmail.com> wrote:
>> >>
>> >> >I'm going through some stuff I have to move (retiring in June) and trying to decide what to keep. I have a Burr Brown 501 dual supply that puts out +/-15 volts with 115 VAC in. The supply is working but I don't know what's its use was originally. It's a compact block and it's heavy, but there's no current rating listed and I haven't been able to find out anything about it. Is it supposed to supply a reference for calibrating meters or is it used as a power supply? Not being adjustable I wonder if it's made for something specific. Any insight appreciated.
>> >> It's just a supply aimed at permanent installation
>> >> in analog circuits.
>> >>
>
>
>
>> I think you'll find it's both low drift and quiet, but
>> it's getting past it's due date w/r to low frequency
>> electrolytic filter caps . . . and even film caps.
>>
>
><<< Given that it's sealed, I figured it's all film caps (although I certainly am not sure), but good quality film caps have never had an expiration date in the ones I've run across the last 50 years or so.
>
If low frequency output ripple increases prior to internal
current limiting, then the bulk reservoir caps will need
replacement.
>
>> I suggested antique value after spotting one on ebay
>> for $$$.
>
>Yeah, I saw that LOL, but as I always said when comes to ebay - "askin' ain't the same as gettin'"
>
>It's small enough where it won't be a burden to store it for a while, so I'll not pitch it out yet.

I've been trying to get a mid-50s G-Limiting Computer into
a suitable museum for the last decade.

It's one of the earliest components used in fly-by-wire
avionics, employing plug-in vacuum tube op amps; the
sort of thing used in the Avro Arrow.

I get the impression that these organizations anticipate
that if they hold off acquisitions long enough, then all
the old crocks will die off and stop bothering them.

The 501 may have been used in analog computing in the 60s.

RL