(Apologies if I boff the thread reply!)
Here¹s a link to a thread on eevb about my 735a, which includes pictures
of the oven internals from another user.
http://www.eevblog.com/forum/testgear/hp-735a-dc-transfer-standard/
Funny you mention your friend in the early 70¹s-about that time, per the
other poster in the above thread, the course cal was completely nixed and
the discrete transistors were replaced with a 723 regulator. Maybe it was
to fix the drift mentioned by your friend. My unit was manufactured in ¹68
so if that¹s the case, it should drift.
I had intended to get some characterization of the 735a. Had it connected
through my Datron 1062s until the one with ratio decided to crap out. For
the 3 mos the setup was running, the 735a is rock solid-FWIW. Will get
everything up and going again after boards.
I¹ve wanted to do a side-by-side of the 731B and 735a. I¹ve been on the
hunt for a 731B for a while-the ones that have popped up on eBay recently
haven¹t inspired confidence. Shameless pitch-I have a very nice EDC 501J
that I¹d be willing to trade 1:1 for a solid 731B, if anyone¹s interested.
On 5/18/15, 11:00 AM, "volt-nuts-request@febo.com"
volt-nuts-request@febo.com wrote:
Re: HP 735A DC Transfer Standard
(Apologies if I boff the thread reply!)
Here¹s a link to a thread on eevb about my 735a, which includes pictures
of the oven internals from another user.
http://www.eevblog.com/forum/testgear/hp-735a-dc-transfer-standard/
Funny you mention your friend in the early 70¹s-about that time, per the
other poster in the above thread, the course cal was completely nixed and
the discrete transistors were replaced with a 723 regulator. Maybe it was
to fix the drift mentioned by your friend. My unit was manufactured in ¹68
so if that¹s the case, it should drift.
I had intended to get some characterization of the 735a. Had it connected
through my Datron 1062s until the one with ratio decided to crap out. For
the 3 mos the setup was running, the 735a is rock solid-FWIW. Will get
everything up and going again after boards.
I¹ve wanted to do a side-by-side of the 731B and 735a. I¹ve been on the
hunt for a 731B for a while-the ones that have popped up on eBay recently
haven¹t inspired confidence. Shameless pitch-I have a very nice EDC 501J
that I¹d be willing to trade 1:1 for a solid 731B, if anyone¹s interested.
On 5/18/15, 11:00 AM, "volt-nuts-request@febo.com"
<volt-nuts-request@febo.com> wrote:
>Re: HP 735A DC Transfer Standard
