Wed, 8 Dec 1999

Hey Dave:

When I was ACE at WRR-FM in Dallas, we had an old Collins 737, 10 KW  FM Transmitter that used the 2H21 Phasitron exciter.  You could yell at the tube and due to the microphonics be heard on the air.  If you turned up the audio.  The output was 1/6 carrier and went into a 829B tripler and then an 829B doubler and then drove a pair of 4-125A's for 250 watts into a pair of 304TL's for 3 kW approx and the a pair of 3C2500's I believe.  In Dec. of 1961 we went stereo using a Gates Dual Cascade, M-6095 exciter (second generation stereo tubes) with a tube type matrix stereo generator that was inserted into the multiplier stages.  We never could make 29.7 db separation at 50 Hz and 15 kHz without tweeking.  Also when we put  it on the air we did it with a Fisher Tuner and an RCA Scope, there were no monitors, the best thing that came along was the Belar detector and the a modified McMartin SCA Monitor then the Collins 900C which we got one of the first being in Dallas....Your mentioning the phasitron sure brought back alot on memories from the deep dark past.....


David Hultsman

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