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Power supply calibration

Power supply calibration

2000-04-06 by Nathan Hunsicker

When I first built my MOTM-900 PS I calibrated it to exactly 15V & -15V,
now that I have 6 modules (and soon to be 10, as soon as I free up some
money) should I be re-calibrating the power supply loaded or only set it
with no modules attached? -Nate

Power supply calibration

2004-05-08 by Paul Schreiber

Only the '950 needs calibration (I receive it set to +-12V). The '900 is shipped
to +-15V.

And yes, I *do* 'scare the crap' out of '950 builders, on purpose. It's SERIOUS
when working with line voltage, ESPECIALLY the 240V overseas.

Paul S.

Re: [motm] Power supply calibration

2004-05-08 by J. Larry Hendry

In the USA, statistically, more people die from contact with what we call
low voltage in the utility business (120v and 240v) than are killed by
contact with all high voltages combined.

Stooge Larry
(off to energize quite a few uF of 138,000 volt capacitors this week)



Show quoted textHide quoted text
----- Original Message -----
From: Paul Schreiber <synth1@...>
And yes, I *do* 'scare the crap' out of '950 builders, on purpose. It's
SERIOUS
when working with line voltage, ESPECIALLY the 240V overseas.

Paul S.

Re: [motm] Power supply calibration

2004-05-08 by Scott E.

Somehow, when Larry calls 120v "low voltage", I get the distinct feeling
that I would not care to have his job.

I have never been bothered much by working around line voltage. The only
time I have had a worrisome feeling around electricity was when I was
working as an electronics tech in the early '70s. We had an old piece of
HP gear that needed repair. It was a square wave generator that provided
up to 50v p-p and plenty of current. Must have weighed 150lbs. And
tubes. Lots of 'em. And a 1300v power supply. Made me VERY nervous
checking circuit voltages while I was troubleshooting. The other high
voltage items I was around were the 6kv klystrons, but they were pretty
easy to avoid.

Stay safe, Larry.

Scott E.
===================================================================
J. Larry Hendry wrote:

Show quoted textHide quoted text
> In the USA, statistically, more people die from contact with what we call
> low voltage in the utility business (120v and 240v) than are killed by
> contact with all high voltages combined.
>
> Stooge Larry
> (off to energize quite a few uF of 138,000 volt capacitors this week)
>
>
>
> ----- Original Message -----
> From: Paul Schreiber <synth1@...>
> And yes, I *do* 'scare the crap' out of '950 builders, on purpose. It's
> SERIOUS
> when working with line voltage, ESPECIALLY the 240V overseas.
>
> Paul S.
>
>
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>

Re: Power supply calibration

2004-05-08 by Robert van der Kamp

On Saturday 08 May 2004 16:37, Paul Schreiber wrote:
> Only the '950 needs calibration (I receive it set to
> +-12V). The '900 is shipped to +-15V.

Ah, my wrong.

Show quoted textHide quoted text
> And yes, I *do* 'scare the crap' out of '950 builders, on
> purpose. It's SERIOUS when working with line voltage,
> ESPECIALLY the 240V overseas.

Oh yes, I totally understand. I hope I didn't suggest
otherwise.

- Robert

Re: Power supply calibration

2004-05-09 by sasami@hotkey.net.au

>Somehow, when Larry calls 120v "low voltage", I get the distinct feeling
>that I would not care to have his job.

You wouldn't have liked my job either then. Mains here was "only 240V". One
transformer the company built failed at around 9000V between the windings -
I was meant to tolerate 17000V, so a new design had to be done. The original
designer had neglected this fact! The failed one now runs my garden lights.

Ken
_______________________________________________________________________
Ken Stone sasami@... or ken@...
Modular Synth PCBs for sale <http://www.blaze.net.au/~sasami/synth/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

Re: [motm] Power supply calibration

2004-05-10 by Brice D. Hornback

I have an old Kenwood TS-820 ham radio that has about 900V inside it on the
output tubes. I had to check the supply voltages one time and it took me
quite a while just to get up the nerve to do it (and make sure my hand -
other was in back pocket - wasn't shaking at the time!). :-)

As a side note... when changing the heating element on a 220V water
heater... turn off the circuit breaker FIRST before sticking a wrench in
there! Duh! Don't ask.

Further suggested reading:
http://hypertextbook.com/facts/2000/JackHsu.shtml

- Brice
(who considers anything over 15V "high voltage")

----- Original Message -----
Show quoted textHide quoted text
From: "Scott E." <yahudinyhwh@...>
To: <motm@yahoogroups.com>
Sent: Saturday, May 08, 2004 11:53 AM
Subject: Re: [motm] Power supply calibration


> Somehow, when Larry calls 120v "low voltage", I get the distinct feeling
> that I would not care to have his job.
>
> I have never been bothered much by working around line voltage. The only
> time I have had a worrisome feeling around electricity was when I was
> working as an electronics tech in the early '70s. We had an old piece of
> HP gear that needed repair. It was a square wave generator that provided
> up to 50v p-p and plenty of current. Must have weighed 150lbs. And
> tubes. Lots of 'em. And a 1300v power supply. Made me VERY nervous
> checking circuit voltages while I was troubleshooting. The other high
> voltage items I was around were the 6kv klystrons, but they were pretty
> easy to avoid.
>
> Stay safe, Larry.
>
> Scott E.
> ===================================================================
> J. Larry Hendry wrote:
>
> > In the USA, statistically, more people die from contact with what we
call
> > low voltage in the utility business (120v and 240v) than are killed by
> > contact with all high voltages combined.
> >
> > Stooge Larry
> > (off to energize quite a few uF of 138,000 volt capacitors this week)
> >
> >
> >
> > ----- Original Message -----
> > From: Paul Schreiber <synth1@...>
> > And yes, I *do* 'scare the crap' out of '950 builders, on purpose. It's
> > SERIOUS
> > when working with line voltage, ESPECIALLY the 240V overseas.
> >
> > Paul S.
> >
> >
> >
> >
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
>
>
>
> Yahoo! Groups Links
>
>
>
>
>