The 334 has an Automatic Nulling (A6 board) circuit which uses lamps and a single detector. I see no chopper.
On Tue, Apr 7, 2020 at 12:04 PM Jeremy Nichols <
jn6wfo@...> wrote:
Purely out of curiosity, what is the purpose of a chopper in a 334 distortion analyzer? HP used choppers in a lot of their DC voltmeters to convert the DC to AC. They¡¯d run the AC through some amplifiers and then convert back to DC to run the meter. That took care of the old DC amplifier drift problems. Since a distortion analyzer is already working with AC, I would think a chopper wouldn¡¯t be necessary. Obviously there¡¯s something I¡¯m missing.?
Jeremy?
--
Jeremy Nichols
6.
Michael A. Terrell