[MRCA] April 23 PRC-47 no transmit update

[J Mcvey]

That is probably normal in a "no load" condition, it's not causing your problem.
You have to be more specific about what conditions you measured that  was it key down or in receive. It makes a big difference.  If that was measured in tx mode, it sounds more  like there is no tube bias or a dead PA.
Tubes rarely short, but I suppose anything is possible. If you have good HV, why would you think that?

You might be biting off more than you can chew...


 

    On Monday, April 23, 2018, 3:10:58 PM EDT, James Green <jagreen3 at sbcglobal.net> wrote:  
 
 I measured the PL-177 plate tube B+ at J101 with the tube installed & a 5 amp slow blow fuse in the 20 amp fuse holder.  The fuse blew. I next put in a 10 amp slow blow fuse. This did not blow. I measured B+ Low at 810 VDC and Hi at 1,810 VDC Both are higher than expected. Lo should measure 650 VDC and Hi should measure 1,500 VDC.

I was just wondering if I had a shorted PL-177 tube. How does one determine this?
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