07-23-2007, 03:44 PM
Ron-
Room for three (actually 4) tubes wasn't that difficult on the 37-620 chassis.
Since the original xfmr had smoked I used a Greenlee to punch a new hole for a 5Y3 rectifier next to the 6F6; with the two filter caps now underneath, that left room for two octal gas regulator tubes, 0D3; on the RF deck I removed the large electrolytic and installed another octal socket in it's place- that became a second IF amp (another 6K7). All this makes for a VERY sensitive and stable radio especially with a balanced antenna input (coax-to-toroid).
The escutcheon was replaced with a larger console type with the shadow meter window; behind that is a large bright LED. I will pull the chassis in the next couple of days to see how I connected the LED but it was somewhere in the AGC circuit (not the AGC line).
Room for three (actually 4) tubes wasn't that difficult on the 37-620 chassis.
Since the original xfmr had smoked I used a Greenlee to punch a new hole for a 5Y3 rectifier next to the 6F6; with the two filter caps now underneath, that left room for two octal gas regulator tubes, 0D3; on the RF deck I removed the large electrolytic and installed another octal socket in it's place- that became a second IF amp (another 6K7). All this makes for a VERY sensitive and stable radio especially with a balanced antenna input (coax-to-toroid).
The escutcheon was replaced with a larger console type with the shadow meter window; behind that is a large bright LED. I will pull the chassis in the next couple of days to see how I connected the LED but it was somewhere in the AGC circuit (not the AGC line).
Pete AI2V