[BC] Re: Super Modulation

[Phil Alexander]

On 12 May 2005 at 8:07, DHultsman5 at aol.com wrote:

> Hello Phil ALexander
>  
>  
> I think you mentioned that you were with Gates when they came out with the  
> Super Modulation  BC-5H-1A 5 kW. transmitter.  Do you recall the  
> specifications on positive peaks?  Do you recall the reasons the FCC  
> imposed the positive limit?

AFAIK there was no formal spec. It was (in my time) a "special" mod that everyone
knew about and they got away with it because the modulator section of the 5P2 and
10P were essentially the same except for PS current available, reactor and mod
xfmr itself. Once you use the same PS as a "mfg. economy" and get type acceptance
for building the 5P2 box with 10P iron, the rest is up to the station, their audio 
equip. etc. <g>

The reason I always heard for the FCC limit (but never officially) was it wasn't
right for a 5 kW station to get the same coverage as a 10. <g> And, I guess some
thought it unfair that everyone couldn't do it with older equipment. From a
practical standpoint, the next step was DSB with partially suppressed carrier
if they did nothing, because the technology was available and things like the
Amplifuzz were already on the market. They had to do something because some
stations were hitting +175 -99.5 (though we never admitted that could be done)
and better audio processing was beginning to develop. I don't know, maybe Harold 
Kassens (who was Chief of the FCC/BB in those days) was worried about what would 
happen with adjacent interference if they didn't do something. <g>  Consider what 
you might do with 250 W and +1000% a/k/a DSB, mostly suppressed carrier. <g>  
Ah, how times have changed. <ggg>

Phil Alexander, CSRE 
Broadcast Engineering Services and Technology 
(a Div. of Advanced Parts Corporation) 
Ph. (317) 335-2065   FAX (317) 335-9037




-- 
No virus found in this outgoing message.
Checked by AVG Anti-Virus.
Version: 7.0.308 / Virus Database: 266.11.8 - Release Date: 5/10/05