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Old August 27th 08, 01:57 AM posted to rec.antiques.radio+phono,rec.radio.amateur.homebrew
John Byrns[_2_] John Byrns[_2_] is offline
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First recorded activity by RadioBanter: Apr 2007
Posts: 61
Default WTB : LPAM Part 15 Transmitter BCB

In article ,
Peter Wieck wrote:

On Aug 26, 6:10*pm, Syl wrote:
Peter Wieck a écrit :

For the money, and if you can get to Kutztown, I will have a
consignment of SSTRAN AMT3000 units. $80, including all taxes and with
the SMT chip already installed.


Peter,

That transmitter is NOT FCC part 15 compliant for what I know.

This would be misleading as the OP requests a part 15 transmitter
BCB.


From the website:

· Legal to use in the US, no FCC license required

· Fully compliant with FCC Part 15 regulations

· 100 mW input power

· 100% Modulation

· 20Hz to 20kHz ±1 dB Audio Response

· Very Low Distortion

· Adjustable Audio Compressor/Limiter


This is a misleading statement, the SSTRAN AMT3000 does not include a limiter,
manufacturers claims not withstanding. A traditional limiter as used with AM
transmitters controls the modulation peaks, either by a clipping operation, or
with a high speed peak activated AGC amplifier, the SSTRAN AMT3000 includes
neither of these circuits. The so called "Compressor/Limiter" used in the
SSTRAN AMT3000 is an RMS controlled AGC amplifier with a knee in its compression
curve. The RMS control means that it doesn't pay any attention to the peak
levels that cause over modulation. SSTRAN calls it a "Limiter" because of the
knee in the compression curve, but it fails to operate as expected of a limiter
to prevent over modulation.

--
Regards,

John Byrns

Surf my web pages at, http://fmamradios.com/