>
>hi group,
>
>peter wrote,
>
>> You'll find the resistor values in very small type ( and I mean small! -
>> too small for comfort for a 50 year old like me) on the diagrams and the
>> footnotes, where they equal up the resistors for minimum drift, and
>> specify drifts with resistors <10k.
>
>as i recall from my years in the semiconductor device biz,
>specifications like this are written for conditions where the device
>is giving near "optimal" performance. it doesn't mean other values
>won't work, but it's sure a good place to start. if your idea of "optimal"
>performance (e.g. rfi immunity) is different from the mfgrs' idea of
>"optimal" performance (e.g. low drift) then the circuit
>configurations can be different. but everybody knows that already.
Apparently, not quite everybody, George. After the RFI-mod being
questioned, the drift, as well as the voltage change in the presence of
RF was not observable on a 3 1/2 digit DMM--so it seems to me that more
discussion is much adoo about nothin'. .
- Rich -
R. L. Measures, 805-386-3734, AG6K
--
FAQ on WWW: http://www.contesting.com/ampfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|