GTX mobile transmit power
Posted: Mon Apr 11, 2005 11:46 am
I had nothing to do last week, so I spent some time with my GTX 900 MHz mobile radio, programming it and measuring the transmitter output power at various frequencies across the amateur band. My unit has a code plug that fixed the low power problem (where output power is under 1 watt at 927.5 MHz but 11 watts elsewhere). Here are the results.
MHz, Watts
902.5, 12.0
903.5, 11.9
904.5, 11.9
905.5, 11.8
906.5, 11.8
907.5, 11.8
908.5, 11.8
909.5, 11.7
910.5, 11.6
911.5, 19.0
912.5, 11.5
913.5, 11.5
914.5, 19.0
915.5, 11.5
916.5, 7.0
917.5, 18.5
918.5, 3.9
919.5, 11.2
920.5, 11.2
921.5, 19.0
922.5, 12.4
923.5, 6.8
924.5, 18.0
925.5, 3.8
926.5, 11.0
927.5, 11.0
928.5, 11.0
929.5, 11.0
930.5, 11.0
931.5, 11.0
932.5, 11.0
933.5, 11.0
934.5, 11.0
Note that the radio is spec'd to transmit from 896-902, and from 935-941. With 25 MHz splits, the unit only needs to perform well in the repeater input range of 902.0-902.9 MHz and in the repeater output range (for simplex) of 927.0-927.9 MHz. It's possible that choosing frequencies other than XXX.5 would have different results. It was hard enough doing six at a time between programming cycles, so this will have to suffice.
Bob M.
MHz, Watts
902.5, 12.0
903.5, 11.9
904.5, 11.9
905.5, 11.8
906.5, 11.8
907.5, 11.8
908.5, 11.8
909.5, 11.7
910.5, 11.6
911.5, 19.0
912.5, 11.5
913.5, 11.5
914.5, 19.0
915.5, 11.5
916.5, 7.0
917.5, 18.5
918.5, 3.9
919.5, 11.2
920.5, 11.2
921.5, 19.0
922.5, 12.4
923.5, 6.8
924.5, 18.0
925.5, 3.8
926.5, 11.0
927.5, 11.0
928.5, 11.0
929.5, 11.0
930.5, 11.0
931.5, 11.0
932.5, 11.0
933.5, 11.0
934.5, 11.0
Note that the radio is spec'd to transmit from 896-902, and from 935-941. With 25 MHz splits, the unit only needs to perform well in the repeater input range of 902.0-902.9 MHz and in the repeater output range (for simplex) of 927.0-927.9 MHz. It's possible that choosing frequencies other than XXX.5 would have different results. It was hard enough doing six at a time between programming cycles, so this will have to suffice.
Bob M.