[Heathkit] SB-303 no recieve HELP!!!

[Dan Pividal]

Have an SB-303 Heathkit.
Turned it on and no recieve on 80 meters.
All other bands ok.
After 10 minutes 80 came on strong all by itself.
Turned off unit and when I turned it back on a few hours later 80 meters dead again.
After 10 minutes of rig being on 80 meters came up.
turned rig off and went to bed.
Next morning rig dead on all bands and has never come back.
S-Meter only shows a less than 2 on all bands.
None of the bands peak with the pre selector.
I have no extender boards for the unit to trouble shoot.
I have cleaned all contacts and checked for continuety.
I have looked in the manual and no trouble shooting hints for this problem.
If anybody can at least point me in a good direction or help me brain storm I would be mos greatful.
Thanks 
Dan/N4VET