[morzh]

There you go.
Now when that thing happens, you could see if it changes.

[dconant]

Yep Mike. Now it will probably play the rest of the day without problems. So probably won't know until tomorrow.

[morzh]

Patience, Grasshopper.

Think of it this way: eventually you will find out the reason of why it keeps happening. It is not the question of "whether" but rather of "when."

[RodB]

I'm not sure how it should be connected, either. There's a gimmick to the gimmick. I guess we can leave it for now. Just make sure none of the strands are shorting to the 6A8 grid cap wire. From my recollection gimmick wires are usually single strand wire and I always found that curious.

[morzh]

Rod

if by single strand you mean "solid", there's not`hing curious to that; simply speaking, solid wire, when twisted around something, holds the shape without trying to untwist itself, whereas the multy-strand wire does exactly the opposite.

[MrFixr55]

Does the radio totally quit or just get lower in volume?

If it just gets lower, the oscillator is still working. If the oscillator quits, reception quits. Have you replaced the detector or the 1st AF tube?

Try injecting an audio signal to determine if the problem occurs with an external audio input. If you have done so and I did not see the outcome post, I'm sorry.

[dconant]

No, the radio does not totally quit. The reception drops way off. For a local strong station if I turn it way up I can still hear the station. Weak stations are pretty much gone. A Bluetooth plays fine when the reception drops off. All tubes have been replaced with 6A8, 6K7, 6H6 and 6F5 several times.

The stranded wire I use is tinned. The solid wire I have looks cheap in these old radios.

Nothing new to report today, yet.

[morzh]

If the strong station stays, and this means the tuning is working, this means the oscillator is also working.

[dconant]

Well it crapped out again while the antenna ground was disconnected. Going to see about getting another antenna coil before I try to rewind the existing coil. I hope I didn't put in a defective part. Look for my want ad.

[morzh]

OK. You did not do what I suggested? Measure the V-avc on at the cap of the 6A8?
That could tell you right away if you have a defective coil's secondary.


So, a suggestion. Before you buy anything, when the radio craps out, measure the AVC voltage both at C12 and at the Grid Cap of 6A8. If they are exactly the same, as a minimum, your secondary (and most important) coil is good.

And the primary is easily checked with ohmmeter (in fact the secondary is also, but the way I suggested it will check it right when it goes bad). Better yet, checking the primary with ohmmeter ca be done while the radio is on and crapped out, by testing Ohms between the chassis (or the "G" screw contact at the rear antenna connection strip) and "A" screw contact.

[dconant]

Yeah I forgot. Now I have to wait again. Won't be able to do much today.

[dconant]

Change of plans for today. Mike I'm confused about measuring at C12. C12 is in the tone circuit, is this the correct place? I wonder if you mean C2 at the bottom of the secondary coil going to the band switch?

[tbone]

This has been an interesting post to say the least. Intemittents are the worst.

If I read this correctly, the DC voltages seem to be stable when working or not. The AVC voltage will vary based on signal strength, so i think it will be fairly high negative with your transmitter.

Have you tried the radio on a shortwave band to see if the problem follows? I know SW stations are a not the most stable, but some of the time standard stations are. WWV on 5, 10, and 15 are reliable. CHU pumps out a strong signal on 3.330 nights, and 7.850 days. I say this because a different set or section of coils is used which may give a clue.

The other thing I have seen is trimmer caps intermittently shorting out. The mica can get cracked, or it can be dirty. May be worth cleaning them and checking for issues.

I really feel the problem is before the 6A8 because you have stated putting your finger on the grid cap brings in the stations, but immediately goes away when removed. You should get 20-30 ohms between A and G on AM, and less on shortwave.

That’s all I have.

[dconant]

I assumed C2. Turned on radio it was doing it's thing. Term G and A 24.3 ohms while crapped out. Working normal 24.3 ohms.

AVC while crapped out at 6A8 -2.4. C2 -2.4. Normal at 6A8 -4.5. C2 -4.8.

[morzh]

Yes, C2. A line runs cross between C and 2, so I thought it was 12.