The idea to use N connectors in that application is infact basically
wrong. The peak, and repetitive peak ratings of a connector can't be
empirically and automatically evaluated good for the specific
application if the average calculated power is within limits.
73,
Mauri I4JMY
>
> Last century I came upon a system where type N connectors were
> constantly failing. They were used on the output connectors on RCA
> Y-1086 and Y-1070 cavities, which use 7651 tetrodes at 200 MHz. The
> highest power was about 5 kW peak, and 12% duty factor. This is about
> 600 watts average power. Being the drivers for another stage, they
> were subjected to VSWR during tuning of the grid input tuner for that
> state - and no isolator was present. The original cavities were rated
> for the peak but not the average (only 6% DF), and someone TURNED
> THEM UP. The input to the next stage also had N. We removed the N
> and replaced with Shuner 7/16 DIN connectors and mating cables. We
> replaced the Jones micromatch Directional couplers (having N
> connectors) with Weralatone couplers having the 7/16 DIN connnector.
> We got rid of the 7651 and went MOSFET for the 5500 watt stage
> (MRF151Gs). End of problem. Never had another connector failure since
> 1995 changeover.
>
> john
> K5PRO
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