 
			
				July 14th 04, 01:24 PM
			
			
			
	
		  
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			On Fri, 09 Jul 2004 15:15:39 GMT,   (K5DH) wrote: 
 
I recently bought a Drake TR-4C / RV-4C / AC-4 station 
which came from an estate.  The gear is nice and clean 
and appears to be 100% stock. 
 
After I rebuilt the power supply and replaced a couple 
of tubes, the station is operational with the exception 
that I have no push-to-talk (PTT).  VOX works fine on CW 
and SSB.  I replaced the 6EV7 tube, and that didn't help. 
I tried two different microphones and got the same result 
with both of them.  Both mics work fine with my B-Line, 
so it's not a mic wiring or switching problem.  Before I 
dive in with a voltmeter, does anyone have any suggestions 
on what may be wrong, perhaps based on personal experience? 
And yes, I'm aware that the CW key must either be closed 
or unplugged for PTT to function. 
 
Thanks and 73, 
Dean K5DH 
 
 
Dean, 
 
Have you replaced the 6FQ7? This tube controls the TX/RX. 
 
Walt, KA2NJF 
 
		 
		
		
		
		
		
		
		
		
	
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