[BC] Old FCC Audio Proof rules

[DHultsman5@aol.com]

In a message dated 6/4/2006 12:29:54 PM Central Daylight Time,  
dynotherm at earthlink.net writes:

> I  am talking about the 1960's.....I believe you had measure response down  
 to 
> 30 cycles in those days.  I seem to think that distortion may  not have  
been 
> required.   My brain may be full of  cobwebs but I seem to  remember having 
to 
> go down to 30  Hz.

Dave,

Your memory hasn't started to fade. 30 cps was  required in the 60's 
and before. I remember it because it was such a PITA  to get the old
GR pushbutton audio oscillator to kick in at that freq. I  also recall
there was a higher level of permissable THD at 30 ... 4% on AM  IIRC.
Again, IIRC, 10 kcs was an AM proof requirement, and we routinely  
proofed an AM box out to 12 kcs. 



**********************************
 
Phil
 
Thanks for your confirmation.  I was out doing monthly monitor points  
yesterday and looked at an old proof and the forms had blocks for 30 cycles  
response insertions and the curves were plotted to 30 cycles.  On two of  the old 
proofs the work was done, on later proofs the 30 cycle blanks were not  filled in.
 
Dave