[Amps] Henry 1KD5 Reanimation

Mike & Becca Krzystyniak k9mk at flash.net
Sun Aug 20 14:44:08 EDT 2017

Greetings All,

   This past week I recovered a Henry 1KD5 from an gargage sale/estate. 
   It appeared to be an 80M-15M model, that someone added 10M too.

   The amp looked clean so I brought it up slow with a variac.  Some initial
arcing from the HV wires which I quicky replaced.  
   However, up around the 3KV point I start hearing a steady hissing, with
some popping seen on the metering (Ip is flicking +/_ around zero).

   I can't be sure but it sounds like it is somewhere on the HV filter
board, the one that is mechanically holding the caps and bleaders.
   But nothing visible.  Are those boards a phenolic or bakelite or ???  
   Any hints on how to safely trace this down?

   The second issue is centered around the tube and tank.
   The is a Pi-L output and albeit an alleged design improvement, tuning to
get power out has been totally elleusive to the point I thought the 3-500Z
was bad.
   Looking at the cam shafted switched for the padder caps, I noticed that
the cam maybe off by one bandswitch step.

   Can someone tell me if all three of the plate tune padder caps are
"Switched in" on 80M, then 2 on 40M, and one on 20M?
   That is what the schematic suggests to me.  
   But this one has all three caps in on 80+40M, then 2 on 20M, and one on
15M.  It's like someone rotated the cams by one rotation indent.

   Back to the Pi-L tuning, does anyone have a better process for
setting/tuning a Pi-L tank (aside from the presets in the manual and web)?

Thanks in advance.

73  Mike K9MK/5    

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