[georgetownjohn]

Good morning members, While I was repairing insulation on one of the two the black insulated thin wires that go into the bottom of the first IF can, I noticed that one of the tiny wires going to one of the terminals on the bottom of the IF can was broken. I retouched the two wire ends with my soldering iron with a bit of solder. My concern, is the IF transformer going to work or not. I see the 2 resistance reading listed in the schematic for part #33 which is the first IF. Can I check if its good by measuring the resistance? If so do I have to disconnect the IF can wire to make the readings. I certainly hope all is not lost. Thanks, John

[morzh]

In the first place I would confirm the abscense of continuity before reconnecting. Just to exclude stupid things.
If this was a real open, then I don't think a short made of solder (I leave the reliability discussion) would change the parameters: as long as you do not see burnt copper and the continuity is somewhat similar to that shown (if it is shown), it should be ok.

[georgetownjohn]

Thanks once again morzh for your expertise and help. I will do an ohm test and deterine where to check for continuity.  I will remove the IF can in the AM and get started.  If I find tests fail, I'll ask for your help again.   Regards, John

[georgetownjohn]

I am still trying to figure this out.  I took both cans off the IFs and did not see a broken wire so I attemping to use an ohm meter to make sure the coils are ok. The first IF coil, according to the schematic shows one side of the coil going to pin 3 of the plate of the 6a8 tube socket and the other end going to the shadow meter. (But there are 2 shadow meter wires I do not know which one to properly check)
The other coil in the first IF goes from the grid of the 6k7 tube, but there are 3 grids I do not know which one(pin) to test and then connects to ground.   
I hope someone can help.  I am still to new at this to figure this out. Once I get this one, I can verify the 2nd IF.  Thanks,  John 
By the way, I have finally got a schematic file that did not fail so it is attached.  I had to rescan a new version and it worked.  (FYI) the IF transformers in the schematic are parts# 33 and 34.

[morzh]

Usually an IF has 4 pins.
Take any pin, and go through the rest, see if one of them gets you continuity. A few Ohms. Mark the pair, and then test the other pair.

[RodB]

Hi John,
The grids of a tube are numbered starting from the bottom grid. Grid one is usually the input or signal grid. Your 6K7 has three grids and the first grid is attached to the grid cap. You'll notice the wire coming out of the first IF transformer going to the grid cap, that is the IF secondary feeding the 6K7 input grid. The 6A8 has 5000 grids (just kidding). Since this tube has a dual function, the first two grids are dedicated to the oscillator circuit and grid 3 is the input grid which is also attached to the grid cap. Most receiving tubes with grid caps have the signal grid attached to the cap. Later 8 pin octal tubes are identical except for the grid cap and have a S (for single ended) added to the tube number as in 6SK7 or 6SA8.

[georgetownjohn]

Ok, I checked the pair combinations for both IFs and I get ohm readings on them.  While the readings are different than specified in the schematic, it hopefully will be ok.  I did not diconnect any of the IF wires to do this, but instead took the readings at the points where the wires terminated on tube sockets and/or terminal strips. --John

[morzh]

Both readings should be in Ohms, not hundreds, not kOhms. Ohms, units to 15-20 Ohm is a typical coil reading.