[volt-nuts] Solartron 7150plus - Chasing AC gremlins

[David C. Partridge]

Apropos of nothing in particular, the values of R82 and C41 are different in the 7151 meter whose floating board is otherwise almost identical.  R82 is 33R instead of 75R and C41 is 47nF instead of 22nF 

Dave
-----Original Message-----
From: volt-nuts-bounces at febo.com [mailto:volt-nuts-bounces at febo.com] On Behalf Of Philip Pemberton
Sent: 14 December 2012 01:44
To: Discussion of precise voltage measurement
Subject: Re: [volt-nuts] Solartron 7150plus - Chasing AC gremlins

* Lifting one leg of R82 (the 75R input resistor for the RMS-DC
converter) and injecting 2V pk-pk 400Hz from a sine generator (Zo=50R) results in a stable reading of ~0.65V RMS on the 7150 display, the same as my Tek DSO reports. The reading is still drifting around a bit.