[Yaesu] FT-1000D and Alpha 87A

Steve Lawrence smlx at earthlink.net
Sun Jan 25 11:18:56 EST 2004

The D's circuit looks like this:

The Band Data connections come from the RF unit. S1002 switches the  
collector of Q1029 to pin 2 of the Band Data connector. This device is  
a FA1A4P (NPN). It is a 50v (Vceo) 100 ma device. This transistor also  
operates the TX relay, RL 1005, at 12 volts. NEC device specs can be  
found at:


If you don't turn the TX relay off, you will wire-or the FT1000D's 12  
volt line through the relay coil to whatever is connected to Band Data  
pin 2. NOT a good idea.

The circuit is designed to key only a positive voltage. Otherwise you  
must use an external switching interface or you will pop the transistor  
and then the TX relay won't work either.

I have been using a cable from pin 2 of the D directly to and the Alpha  
87A "Relay" RCA connector for several years. I've never had a problem.

73, Steve WB6RSE

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