My 7G605 would not pick up any stations; only humming. After determining that the electrolytics were not the problem I was adjusting the "D" trimmer screw on the IF transformer can and suddenly I picked up a station very clearly. I noticed it was not the actual turning of the screw that pulled in the station but was in fact downward pressure on the screw!!! I was able to pull in many shortwave staions also. After about ten minutes I heard a faint click and the station cut out. A slight downward pressure on the "D" screw started the set playing again for a few minutes and it cut out again.
Does anyone recognize what is happening here and maybe have a solution? My thinking is that something is shorting out inside the can. I'm reluctant to remove the can until I know what I'm supposed to be looking for and maybe I should have a replacement can ready to pop in here. I've never removed one of these cans and I would appreciate any help you could give me.
Thanks; Andy
[IMG]http://i31.photobucket.com/albums/c395/twocats43/HPIM2141.jpg[/IMG]

In order to diagnose this, the can will have to come off. With power off and respect for delicate components, you should be OK. Power it back up and gently push down on the screw with a plastic probe while listening for a reaction to locate the trouble. Remember that B+ voltages are here. It may be a broken solder joint or similar poor contact. Avoid using sprays or cleaners on the components as this could cause hopeless, irreversible de-tuning of the cap/coil set-up.

: In order to diagnose this, the can will have to come off. With power off and respect for delicate components, you should be OK. Power it back up and gently push down on the screw with a plastic probe while listening for a reaction to locate the trouble. Remember that B+ voltages are here. It may be a broken solder joint or similar poor contact. Avoid using sprays or cleaners on the components as this could cause hopeless, irreversible de-tuning of the cap/coil set-up.

Yes, you are going to have to remove the can. Have a good look at the everything with a magnifying glass. I have found dead bugs, and years of dust and dirt inside have caused problems. You can use that air in a can to blow out the adjustable caps with care. Look too for old solder joints that look crusty ect. I'm sure you will be able to fix it.

: In order to diagnose this, the can will have to come off. With power off and respect for delicate components, you should be OK. Power it back up and gently push down on the screw with a plastic probe while listening for a reaction to locate the trouble. Remember that B+ voltages are here. It may be a broken solder joint or similar poor contact. Avoid using sprays or cleaners on the components as this could cause hopeless, irreversible de-tuning of the cap/coil set-up.

Hi Walt; Thanks for your quick reply. I removed the can and checked all the solder joints. They appear to be OK. The fine copper wires from the coil appear to be intact. I did notice that at the bottom of the coil, which is impregnated with wax, that the whole bottom appears to have split around the coils circumference. I tried to get the station back by pressing down on the "D" screw but no success.
This can is marked 95 863; 455 K.C. I have a couple of cans from a 6G601 set and they are marked 95 904; 455 K.C. and 95 905; 455 K.C. Could either one of these cans be used as a substitute?
Thanks again;
Andy

:: In order to diagnose this, the can will have to come off. With power off and respect for delicate components, you should be OK. Power it back up and gently push down on the screw with a plastic probe while listening for a reaction to locate the trouble. Remember that B+ voltages are here. It may be a broken solder joint or similar poor contact. Avoid using sprays or cleaners on the components as this could cause hopeless, irreversible de-tuning of the cap/coil set-up.
:
:
:
:Hi Walt; Thanks for your quick reply. I removed the can and checked all the solder joints. They appear to be OK. The fine copper wires from the coil appear to be intact. I did notice that at the bottom of the coil, which is impregnated with wax, that the whole bottom appears to have split around the coils circumference. I tried to get the station back by pressing down on the "D" screw but no success.
: This can is marked 95 863; 455 K.C. I have a couple of cans from a 6G601 set and they are marked 95 904; 455 K.C. and 95 905; 455 K.C. Could either one of these cans be used as a substitute?
:Thanks again;
:Andy
:
:
:Thanks Warren for your help; I suppose I should just go ahead and resolder all of the connections to be safe. There was a cardboard insulation sleeve all around the inside of the can so nothing looked as f it could short out. Also I checked the 47k ohm resistor in the can and it read 52K ohm so it was within tolerance. I'll let you know how I make out after soldering.
Thanks;
Andy
:
:
:
:
:
:
:
:

::: In order to diagnose this, the can will have to come off. With power off and respect for delicate components, you should be OK. Power it back up and gently push down on the screw with a plastic probe while listening for a reaction to locate the trouble. Remember that B+ voltages are here. It may be a broken solder joint or similar poor contact. Avoid using sprays or cleaners on the components as this could cause hopeless, irreversible de-tuning of the cap/coil set-up.
::
::
::
::Hi Walt; Thanks for your quick reply. I removed the can and checked all the solder joints. They appear to be OK. The fine copper wires from the coil appear to be intact. I did notice that at the bottom of the coil, which is impregnated with wax, that the whole bottom appears to have split around the coils circumference. I tried to get the station back by pressing down on the "D" screw but no success.
:: This can is marked 95 863; 455 K.C. I have a couple of cans from a 6G601 set and they are marked 95 904; 455 K.C. and 95 905; 455 K.C. Could either one of these cans be used as a substitute?
::Thanks again;
::Andy
::
::
::Thanks Warren for your help; I suppose I should just go ahead and resolder all of the connections to be safe. There was a cardboard insulation sleeve all around the inside of the can so nothing looked as f it could short out. Also I checked the 47k ohm resistor in the can and it read 52K ohm so it was within tolerance. I'll let you know how I make out after soldering.
:Thanks;
:Andy
::
::Hi Warren and Walt;
Well good news; I resoldered all 6 terminals inside of the can, turned on radio and picked up a station fairly loud. I reassembled the can and turned it on again. The station was there but not as loud. I adjusted trimmers A,B,C,and D by ear but could not get a loud volume; (not as loud as when the can was removed). It appears as if there was a bad solder connection. I'll have to live with the reduced volume until I can do a proper alignment. Thanks for your help in getting the problem solved!!!!
Andy
::
::
::
::
::
::