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Having recently completing a rebuild of a 37-9 I have some questions concerning tuning. 
The electronics are actually a combo  of a 37-9 RF assembly and a 37-10 audio/power supply and a 37-10 if assembly. 
After replacing the caps, resistors, rubber mounts and a coil repair I was able to pick up a couple of very weak stations.
I have never aligned a receiver before but was able to do a if alignment that brought in brought in stations very well.
The first if coils peaked nicely as did the 2nd if primary adjustment. However the trimmer across the secondary of the second
if bottom out (tightened  down) before peaking and dropping back down. Any thoughts as to my next step to improve this adjustment.

When aligning the dial the procedure says to place the 520 K. C. mark midway between the index line and the glowing beam. 
I'm not sure what they mean by the "index line". The rest I understand. 

I will probably need some advice as to tuning the b ands but will wait till I get this correct first 
I am using a HP 3312A function generator and HP 465 scope to align as I do not have a VTVM at this time. 
Any help is greatly appreciated.
Tom


Messages In This Thread
37-9 - by tomg - 04-08-2022, 06:56 PM
RE: 37-9 - by Mondial - 04-08-2022, 11:29 PM
RE: 37-9 - by tomg - 04-09-2022, 02:05 PM
RE: 37-9 - by mikethedruid - 04-09-2022, 03:43 PM
RE: 37-9 - by Mondial - 04-09-2022, 05:59 PM
RE: 37-9 - by tomg - 04-09-2022, 10:38 PM



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