[Elecraft] KPA-1500 No Power Out (TX LED Does Not Come On)

[Richard Thorne]

Came out to the shack this morning and the KPA-1500 is not going into 
transmit.

I verified that the PTT cable is shorting when the Flex 6600 goes into 
transmit.

The amp operates properly otherwise. The ATU works, it shows the power 
out from the 6600, it just won't go into transmit (no Red TX LED).

I did upgrade to firmware 2.48 yesterday and the amp worked fine.  I 
downgraded to 2.38 this morning, same result, the amp will not go into 
transmit.

What am I missing early this morning with only a half cup of coffee.

Thanks

Rich - N5ZC