Vintage HP Current Amplifier, Model 1111A

Apr 19, 2007 4 Replies
E

Hi, everyone. Can anyone point me in the direction of the specifications for Subject instrument. I've just refurbished one that I rescued from the dumpster, but I'm not sure over what frequency range it works - checks out good at 60 Hz, but what about audio frequencies? BTW, it consists of three pieces:



  1. a magnetic split-toroidal probe, plus coax cable,
  2. an electronics unit that drives a scope on the 50 mV/cm setting, and
  3. an old fashioned "wall-wart" p/s (before that term was in vogue!) - all built like a brick outhouse, typical of HP from that era. Cheers, Roger (P.Eng, EE, Canada) PS. I'd appreciate an email to "analogdino 'at' rogers 'dot' com" as I don't get back here often! Many thanks.

Vote
Twitter Facebook LinkedIn
S

There are places wher you can download or buy manuals. Google. HP might even have a site itself.

Bill

-- Fermez le Bush--about two years to go.

Vote
Twitter Facebook LinkedIn
T

the test instrument division, now called Agilent, has a great many manuals. Unfortunately not this one. they call it a "probe amplifier"

formatting link

you might give these folks a call

formatting link
. i seem to recall seeing quite a library of manuals last time i was there.

Vote
Twitter Facebook LinkedIn
E

Thanks, Bill, but did not find it. I got some specs from Dave that look interesting (higher bandwidth than I expected) so will set up some tests. Cheers, Roger

Vote
Twitter Facebook LinkedIn
E

I got this kind email from a David G.

"The 1111A model number is just for the amplifier. The usual 1110A probe has a specified bandwidth of 850Hz-45MHz, so the amp is good up to at least 45MHz. It sounds like you have a different probe though."

I replied: "David, many thanks. My probe is, indeed, a model 1110A marked "1110A AC current probe 1 mV/mA". I'm surprised I got any 60 Hz signal at all out of it (I clamped it around a single lamp cord), but the low end of 850 Hz does explain why it seeemd to read very low - I thought my scope was out of calibration. I'll retest it using a sig. gen, audio amplifier and a 4 ohm speaker load, measuring the current up to 15 KHz or so (and comparing to 60 Hz, too!) Cheers, Roger"

Vote
Twitter Facebook LinkedIn

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required