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Cone sentric tuning questions
#1

Am in the final redoo of a 38-7, (still need a range 1 ant. coil).Have listed in wanteds. Question here is How do you change the cone presets?
I assume they loosten by unscrewing somehow and then tightning? I have tried using a screwdriver on the large slot in the tuning knob while pressing in on it while engaged on a cone but nothing catches to do anything. Is that how you supposed to do it?
Also the muting wire was removed so I re-connected it and got a lot of noisey static when tuning. Was that a weak spot and previous repairman removed it?
This set also had a tuning capacitor problem I've never encountered.
The osc. section on the lower 1/3d of the travel the rotor plates shorted out on the mounting of the stator. about half of the rotor plates touched and I ended up reducing the rotor slightly with a dremmel sander. I'ts ok now, just never had that problem before.

Anyway need advice on the cone adjustments. Also how to remove the fine tuning knob to replace whatever was there for friction.
Don
#2

Chuck has this info on his site. It was very helpful to me.

http://www.philcorepairbench.com/conecentric/index.htm
#3

I made mine from a long allen wrench. Ground down two sides,and then used a dremmel with a disc to cut the slot in the middle. Works great. You can use a thin long flat blade screwdriver and work the tip.
#4

OK. I'll give it a try. Now while I have the knobs removed, what do I replace on the back side of the vernier knob to make it functional again. It just slips on the knerled bezel.
#5

Just the spring that slips on first. That knerl on my 38-4 only seems to work turning clockwise while pushing inward. It barely grips the bezel. Try to adjust the bezel/dial toward the left a hair.
Tune in your stations and lock the cones. I never had to adjust them after that.
#6

Is there enough friction on yours to tune normally. I would like the vernier function for careful tuning on SW. as well. I know a friend that has a 38-4. I may go look at his.
#7

It works fine turning clockwise...counterclockwise it slips quite a bit.
#8

Hi,
I placed a rubber O ring on the back of the vernier knob. It stayed in place, but you could have put a dot of super glueat about 4 points to hold it in place.
Now, it grips the metal dial ring and provides great fine tuning.

For the Cone Centric parts. You might want to loosen the lube the nut on the back of the ring. That way, they will slide easy when setting, and keep you from damaging the small slot at the top of the cone. Th[/i]e one I worked on, the cones would not come off with a screwdriver. They were frozen on over time. Gripping the cone, I loosened them, then they were east to tighten and loosen with a tool you make.
#9

Just what I was going to try Gary. I haven't got back to it while waiting for the new Ant coil to arrive. I Will do exactly what you have done. Thanks. Also Thanks to Jimmy for the idea on the tool.
Don
#10

Gary,good idea with the o-ring! Tubadon,your welcome.




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