[Heathkit] SB 220 loading problems

[David Thompson]

I have a SB 220 that I picked up several months ago.  It has 10 meters
converted to 6 meters and puts out about 800 to 900 watts there after I
replaced the strap to the tank coil and used silver solder.
It puts out 1200 watts on 20 but on 80, 40, and 15 only outputs 300 to 400
watts.  Plenty of plate and grid ..so it appears that there is not enough
loading.

I also noted the plate voltage is reading 800 volts on CW and 1100 to 1300
volts on SSB but using an outside voltmeter its about 2900 volts on SSB
actually.  I had this problem on a SB 220 I borrowed
back in the early 80's.  I remember the tech at the Atlanta Heatkit store
telling me this was very common in SB 220's but fixed in the later models
(Sb 221, HL 2200).

I have a nice copy of the manual with all pictorals and schematics.  Before
I dive in does anyone have any ideas where to start on the loading problem.
The 6 meter conversions appears to follow an article in a 1964 CQ magazine.
It does not appear that any of the circuit would affect the HF bands.

Reply to k4jrb at juno.com or the reflector as my earthlink spam blocker makes
some mad (I do get the messages without you doing anything!).

Thanks 73 Dave K4JRB   Too many projects as always..