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38-10 Won't Align Properly
#1

I did a complete overhaul on my 38-10 and it works great except the stations don't align with the dial face. Local station 1260 comes in at 1700 on the dial. All stations that I receive are offset by this amount. I performed a good alignment and everything reacted as it should and the set works great. I set the tuning condenser fully meshed and align the "Glowing Beam Indicator" with the index marks as shown on my paperwork, perform my alignment, but everything is still offset.

Haven't had this happen before and I don't really know what to do. Any help would be really appreciated.

Thanks,
Johnny
#2

Hi Johhny,

Symptom suggest the oscillator is running too slow. You may have inadvertently aligned on the 2nd harmonic of the oscillator. See if loosening the trimmer adjustment 7 is possible to get the oscillator frequency running faster. With a station at 1200, the oscillator should run at 1670 kHz in the case of your radio having an IF frequency of 470 kHz. Your padder adjustment 9 may need loosening up too if it was tightened down as well.

Richard
#3

Those padder capacitors often get gummed up and cn't do their jobs. I try to dis-assemble them, clean the mica very gently with water, the rest with deoxit, let the whole assembly dry down, re assemble then do the alignment. Hope this helps some.
#4

Well I just love learning new stuff. Did a little more cleaning and slowly adjusted #7 and #9 and was able to bring the set in perfect. I guess I've been lucky on all my Philcos because I've never had to adjust anything but the IF's when aligning. In this case I kept moving the dial closer to the 1260 station and then adjusting 7 & 9 until the station came in clear. Finally I was at 1260 and it tuned in great. All other stations are where they're supposed to be also.

Thanks for the help. Always appreciated.

Johnny




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