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Ok now we are getting somewhere! Remove the coil. Trace from the connections to the coil winding that is open. It will need to be rewound. I'm thinking that it will be the smaller of the two. If you are lucky that winding will be on the outside where it can be serviced. If this is the case carefully unwind it while counting the turns. Also noting the direction. I don't think that part of the coil that is open is frequency determining it's part of the feedback circuit. Post a pic of the coil before you remove the bad part.
Not much longer and we'll have it working!!
Terry
If you like PM me and I'll pass along my PH# if you need some moral support.
(This post was last modified: 06-02-2012, 07:15 PM by
Radioroslyn.)
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Will give this next fix a go. Will post photo of coil. What size wire? I have 34 in stock.
What about the part 14? Will 700 mmfd be acceptable?
Thanks,
Joe
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We can hold off on 14 for now. 34 maybe a bit large probably 38g is original
Terry.
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Will have to track down some 38 magnet wire.
Thanks,
Joe
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Removed coil after carefully drawing connections.
I rechecked readings at both windings and am getting about 4.7 ohms on each. Is this about normal? Can't seem to get the photos on this message. Keeps telling me file is to large. No green spots on coil. Windings are securely soldered to terminals.
Could the problems I am having go back to the broken stud in part 13? I did manage to get the old stud out and replace it.
Thanks,
Joe
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Measure the resistance across #13, Should have no resistance (open). A little unlikely but possible that the primary and secondary would have the same resistance.
Terry
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No resistance across #13.
.003 mica cond.-#12 needs replacing -probably have to order this. Does # 12 have to be replaced with a mica cond.(dumb question?) I will check coil resistances again tom.
Thanks again,
Joe
(This post was last modified: 06-06-2012, 07:57 PM by
jph14.)
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Yup better go with mica. If you don't have the proper value you can always parallel a few together. Have seen a few that didn't show any green spots but fell apart when unwound.
Terry
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Should I still rewind the coil? If so, should I start with the lower coil? Any secrets to unwinding?
Still waiting on 38 wire. Had to order mica caps- I hardly have any of these in stock.
Thanks,
Joe
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Post a pic of it so I can see what we're getting in to.
Terry
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Tell you what let me pull the coil out of my 66 and see how it measures up with yours. Mine is untested don't know if it is good or not.
Terry
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Replaced #14 and #12. Re-installed oscillator coil, brought voltage up slowly and we had music- channels pretty much across the dial. Sounds great. Went to sit the radio from its side to bottom and radio stopped. Checked back underneath and saw a slight arc at waveband switch # 2. Wire is off. It comes from ant. trans. #4 to ? Will have to get the waveband switch down and look. Not sure about switch. Remember it was broke when I got this. I did repair broken parts but maybe more here than I fixed. Will check on this next time I can. Are these available or can they be bypassed? Not overly concerned with shortwave band.
Thanks to all,
Joe
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That great news!! If it will help I can snap a pic of my band switch so you can figure out where the wire goes. I don't know if the mdl 60 uses the same switch but it was a very popular set. You could probably find a junker much easier than the 66. The SW coverage on the 66 is pretty good with a couple of ham bands and SW broadcast bands. The 60 stinks not much at all on it's SW band. That's one of the reason I picked up a 66.
Terry
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Terry,
I have another model 66 that I got for parts. Fortunately this one works
so I will be comparing the two switches when I get another chance to work on them. Will post pictures when complete.
Thanks,
Joe
Are these switches available anywhere or rebuildable?
