flex5000a Keyline issue help

Rich Ferguson

Flex5000A radio and clean install with power sdr 2.8.0.130. Problem is the amp relay jack tx1,tx2 or tx3 when activated does not shunt to ground. I also measured when the ppt closed a.6 Volt on the active tx1,2,3, rca port. Zero volts when ptt is not keyed.  I have tried 2 different flex5000a radios with same result. Trying to figure out if it is software,firmware, or bad darling-ton pair transistor in both radios. Also is their some kind of work around to activate the RF amplifier key line.

David Umbaugh

Call me to discuss. I think I had the same problem a couple years ago. 330-283-1914

Tom Martin

I use a Ameritron ABR-704 with DDUtil ver 3.2.6.00
Hopefully this is what might help you. It keys my ALS1306 just fine
Tom Martin W7TJM

Fred Friedl

Under "ANT" on the top bar of the PowerSDR software, do you have one of the switch relays checked off?

Fred - WX4US

Rich Ferguson

I have all 3 checked the only change when ptt closes is .6 volt on connector when ptt is closed. 

Dudley WA5QPZ

Rich, The TX1-3 outputs are open collector, and need a positive voltage applied before seeing a change on a meter. In other words, there is no pull up voltage on the outputs. You can apply a less than 50 volt , current limited DC voltage and should drop to roughly .6 volt dc but less than 100 ma. DO NOT connect a cathode keying circuit to the TX outputs as it will wipe out the keying chip. 73, Dudley WA5QPZ