I have converted an SB220 and a TL922 for 6M. Both will produce 1300W PEP
6M.
( FYI I have converted an SB200 and that gave 600W PEP)
A stock L4-B will easily produce 1KW PEP on 10m and should do the same on
6M.
Note:
You need to ground the grids directly.
You should use a PI (not T) on the input with the PI output cap right
next to the cathode. I use compression trimmers.
You should reduce the turns on the plate choke and cathode choke to
about 1/3 of what they were originally.
You should use an L-PI on the output. The L is necessary to overcome
the output cap of the tubes. I used the original TUNE cap with most
of the plates removed, and a new LOAD cap.
The open frame antenna relay should work fine. You will need to add a
little cap, maybe around 10pF, on the normally closed path to
compensate for the relay inductance when the amp is bypassed.
- Paul KW7Y
Paul, Grids are directly grounded, I will try again the PI input (the
output cap is next to the cathode), Plate choke was rewound with 42 turns of
22 ga on 1" porcelain form, I used the stock cathode choke it is 20 turns
each leg on 5/8" ferrite core ( your saying to make this about 7 turns?) I
got rid of the open frame relay and replaced with vacuum relays.
Michelle
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|