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Signal generators / restoring straw cabinets
9/5/1998 12:01:56 PMScott Rhode
2 questions:
Have an NRI Model 88 Signal Generator. Would guess
it probably dates from mid to late 30's. Wondering if
anyone has a manual for it. Have checked with W7FG
and AG Tannenbaum already. Seems to be a pretty low
end model with bands from 170 kc to 60 mc. Can anyone
explain what the coarse attenuator hi-lo switch and
fine attenuator dial (scaled from 1 - 10) do? There
is only one output jack and the lead is missing. Looks
to take a screw on coupling that would have positive
and negative alligator clips on the other end.

Second - What's the best way to clean and generally
brighten up straw cases found on Zenith portable AC/DC
sets? The straw is not worn much, just kind of dingy
from age.

Appreciate any info anyone has. Thanks.

9/6/1998 1:33:11 AMDon Black
: 2 questions:

: Have an NRI Model 88 Signal Generator. Would guess

: it probably dates from mid to late 30's. Wondering if

: anyone has a manual for it. Have checked with W7FG

: and AG Tannenbaum already. Seems to be a pretty low

: end model with bands from 170 kc to 60 mc. Can anyone

: explain what the coarse attenuator hi-lo switch and

: fine attenuator dial (scaled from 1 - 10) do? There

: is only one output jack and the lead is missing. Looks

: to take a screw on coupling that would have positive

: and negative alligator clips on the other end.

: Second - What's the best way to clean and generally

: brighten up straw cases found on Zenith portable AC/DC

: sets? The straw is not worn much, just kind of dingy

: from age.

: Appreciate any info anyone has. Thanks.

Hi Scott,
I'll leave your cabinet cleanup for someone else who has allready done one of these. I don't know your NRI oscillator but if it goes up to 60 mHz that was quite a hihg frequency in the thirties. I have checked an Allied Radio 1936 catalogue which covers a number of makes and they only list one signal generator that goes to 62 mHz.,a Dayrad series 36 for $31-75. It ysn't the most expensive shown but all the others have a top frequency of between 18 to 30 mHz. I suspect your instrument might be a little bit later, into the forties. Thr Hi-Lo coarse and associated Fine Attenuator are used to reduce (attenuate) the output to set the desired signal level. The output lead may have just had a pair of clips but for servicing AM broadcast radios it is usual to use a dummy aerial. This simulates the source impedance of a typical long wire antenna. I hope this helps, Don.




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