[radio1]

All cleaned up, reassembled. It was nasty. Rewire, grommet, install, and see what happens. Emery 'd all the trimmer plates back to shiny. The micas should be okay. The case is not too bad.

[morzh]

Vinegar takes that green off well.

[radio1]

It's the 35 grid cap, was chasing ghosts, it all fell together after I discovered it and moved it around to get some better connection. The OT10SE was in the mailbox today, hooked up and sounds great, plenty of bass an loud, can finish the radio out now, power transformer barely gets warm. Anyone have a technique to fix a grid cap?

[morzh]

Take the cap off, either by gently pulling (if there is no soldering jojnt anymore, it will just come off) or by desoldering it (melting soder and pulling) . Assumed is that the cap is loose.

Clean the cap by melting solder of and violently shaking it once immediately. The solder will come off exposing the hole.

Scrape and tin the end of the wire. Try to not w9rk close to the glass.
Put the cap back. If the wire does not stick out enough, take the cap and using a blunt speric end (or sharp conical) increase the dent.
Put the cap back again, and flood the protruding end of the wire by solder.

I do not know if there are compounds to hold the cap but, if ot disturbed too much, it will ge ok.

[radio1]

The old unit has the NC disease after all, pulled the first detector coil, found it. Top of the primary bad shape, crumbling cellulose. Pulled several wraps of crumbling primary wire and reattached, guess the cotton is gone everywhere. The secondary has green in it also. Put t back in and could hear a big difference, more punchy bass and trimmers bounce more like they should. So a total rewind is in order. Have not pulled the oscillator coil yet, who knows what's in there, the other coils looked good when I pulled those, no green. I am surprised at how the 47 pumps out, hear the potential in this radio. Could try a bluetooth chip driving the negative kink in a 24 to two tuned circuits to each side to an extra 47, driving two baffled 8's out each side of the cab, stereo, just dreaming.

[radio1]

Pondering the situation, before I rewind the failing detector coil, I am curious if anyone has substituted a similar new/NOS coil with similar inductances. I measured mine I think it's one to four ratio 1.3mh to 4. something. So to reason a new old stock coil should give acceptable results, many on ebay and such. The oscillator would be more difficult, but any of the two section coils should be replaceable. The amp section on this unit is fine, what it's pushed with is failing.

Edit- Should receive 30 AWG Essex wire tomorrow. Will start with the oscillator coil as it was crumbling also. Don't know yet what to use for pri/sec dielectric, studying up on coil Q and different materials. Painters masking tape possibly, blister pack, don't know if it makes much difference at the broadcast band, will see what happens. Also an Eico 324 should be here soon to align it if all goes well, use to have TV/fm sweep and 20mhz scope, but sweep did not go to the lower KC if I remember.

[radio1]

Received the wire and rebuilt the oscillator coil using plastic blister pack, had it looking good, put back in - nothing, nada, nothing. Well thought it might be the plastic, so to it out and used scotch tape to rewind the RF coupling,  back in, still, nada, nothing. Took it out and did some research and ran across moisture. Baked it twice at 150 degrees 10 minutes each. Put it back in and heard the faint, tweaked, and it is back. Would not have believed it, but good advice as I had washed the former with water to get the grunge off thinking the wax would hold up, so coils don't like it. Doing the first RF coil next , DC leakage is no fun.

Oscillator tapped secondary and feedback done by hand with 30 AWG --

[radio1]

Got back around to this, surprised the unit can be dialed in at all. The 30 AWG wire I used to rewind the oscillator is app. .2 mm diameter vs app. .15 of the original wire. I wired it up to the coil's original center tap hole, then on up the the coil's original top hole to complete the taps. So the original wire is only app. 75% diameter of what I used, then I am app. 75% of the inductance it needs (don't know how linear inductance builds up though, and how diameter affects it yet). I measure .15 mH currently, but need .26 mH to bring the broadcast band's to app. the 260k IF that this unit uses. I thought someone might have put in a different coil at some point and that's why the radio was parked and when I rewired - same problem. The mounting bracket does look newer than the other coil's brackets and has a orange paint dot on it. Could try substituting the 410pf and 110pf as a simpler solution, but don't know if the spread would work out. My .15 inductance bounced against the 410pf = 641.77 khz vs. .26 against 410 pf = 487.46 when pushed against the middle 750rf would be 260khz if. Also, strange to me, since this is my first coil excursion, I measure .25 mH on the coil outside the aluminum case, but inside .15 - I added some turns to the top, but only a few more mH. Playing this radio with the original NC disease coils gave glimpses of AM like I have never heard, tweaking and dialing in in I heard bass and details that were unreal from an AM unit - also some high frequencies that I did not think possible, so I know it's in there somewhere, even though this non AVC unit will vary, esp. at night. I will find it. With this 30 AWG, the 1st RF and osc. coils don't pump out like the 36 or so wire will, but music now sounds like music ungarbled compared against the old corroded coils. Going to try 36 AWG as some have said. It's starting to pop in like it should even though it's on the side of 260 - fun to tweak the IF side best for the current coils, then rock the oscillator and trimmers to get totally different tones and sounds.