[R-390] Cosmos Drift

[Jon]

Thanks for all the comments. Let me explain a little more on the setup. The
radio does not have the ovens on. In fact the oven cover internal to the PTO
is not installed, just the inner one - the one with the value for nitrogen
and of course the outer one along with the insulation. The output of the PTO
goes directly in a counter. I did not fool with the BFO or the CAL for zero
beating yet. Just sitting on freq and watching it drift. The first day it
drifted 95Hz, second day was 380Hz, the third day,330Hz and the fourth day
(today), 250 Hz. A total of over 1000Hz, always increasing in frequency.

The radio room is down stairs in the cellar that was converted into two
room,play room,radio room. I have a dehumidifier always running in the play
room. The door to the shack is always open however not fully. I have not
monitored the temp or humidity but I'm positive the temp variance is within
5 degrees F. The power supply has the conversion to solid state. As for line
variance, not sure but would this cause a steady increase in frequency? It
would seem to me that at some point the temp internal to the radio would
reach some type of quiescent level along with the capacitance and inductance
with respect to the temperature coefficients of the components which would
result in 'hovering' around a certain a freq. Maybe I'm not there yet.
The onset of restoration I 'retubed' I'm sure that I put in a better
tube,that is higher transconductance. I will certainly tried other tubes.
Hope this helps.

Thanks,
Jon