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Linear Mode
37-11 Alignment and Sensitivity issues
N6MKC
Junior Member
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Posts: 11
Threads: 6
Joined: Feb 2013
City: Camino, CA
#6

09-22-2015, 09:25 AM
Okay, many thanks to Chuck for setting me up with the correct documentation for the radio. Sure enough, Service Bulletin 268a contained all the needed secrets. What a difference the correct documentation makes! 

On my sensitivity issue, turns out, my problem is an open RF coil between the RF amplifier section and the Detector/Oscillator section. It's killing the sensitivity on bands 1 and 2. Of course the open is in the super-fine 6.5Ω section of the coil, and not the thick, .5Ω section that would be super-easy to fix. I unwound some of the wire from both ends of the 6.5Ω section, and the break is sadly not near the ends as I had hoped. Looks like I'm in the market for a replacement…
http://philcoradio.com/phorum/showthread.php?tid=13163

Interestingly, the Code 125 RF alignment instructions have you start at 1600kc, versus 18mc on the Code 121 chassis.
(This post was last modified: 09-22-2015, 09:27 AM by N6MKC.)
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37-11 Alignment and Sensitivity issues - by N6MKC - 09-07-2015, 01:55 AM
RE: 37-11 Alignment and Sensitivity issues - by N6MKC - 09-22-2015, 09:25 AM



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