T1 insertion loss

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T1 insertion loss

g4ilo-2
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

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