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
--
FAQ on WWW: http://www.contesting.com/ampsfaq.html
Submissions: amps@contesting.com
Administrative requests: amps-REQUEST@contesting.com
Problems: owner-amps@contesting.com
Search: http://www.contesting.com/km9p/search.htm
|