[Boatanchors] Electronic T/R Switch vs Coaxial Type

[Garey Barrell]

The best electronic T-R switch I used was from a June 1957 article in 
QST.  I believe the author was W3DM.  It used a single 6AH6, and mounted 
INSIDE the transmitter cabinet.   Drew it's filament and plate current 
from the transmitter supply, and coupled to the PLATE side of the output 
Pi-Net via a very small capacitor, meaning that any harmonic energy 
generated by the switch was attenuated by the Pi-Net before reaching the 
antenna.   There was a coax lead from the unit that went to the receiver 
antenna. 

I used one a LOT for several years in a Globe Chief 90 with an HQ-129X 
with no damage to either unit and no TVI problems in a near fringe TV 
area in the pre-cable days.

73, Garey - K4OAH
Atlanta

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