[Elecraft] T1 insertion loss

Julian, G4ILO g4ilo at qsl.net
Tue Apr 12 06:49:57 EDT 2005


The T1 specification sheet makes no mention of insertion loss, so I 
thought I would try to measure it. I used the FT-817 as an exciter, and 
measured the output power using the Elecraft DL1 dummy load and my DMM. 
The FT-817 produced a consistent power output to within 0.01W each time 
it was keyed, and there were no anomalous results to suggest some other 
factor contributing to measurement error.

There was only 0.2% loss when the T1 was "IN", compared to "OUT", and 
this was pretty consistent across all bands. (With such a low level of 
loss it is almost within the limits of experimental error.)

There was a more significant loss introduced by the T1 itself, 
determined by comparing the measured power with it in circuit, and the 
power with the DL1 connected directly to the cable from the radio. This 
loss was 4% at 3.5MHz, 7% at 28MHz and 8% at 50MHz.

Do these figures seem reasonable? I would have expected a bigger loss 
with the matching networks switched in, but a smaller one caused by the 
T1 simply being in circuit.

73,
-- 
Julian, G4ILO
G4ILO's Shack: http://www.tech-pro.net/g4ilo



More information about the Elecraft mailing list