[MICHAEL CHAMBERIS]

My resto is progressing, Im in need of a 1936 660 chassis, or 665, 680 for parts. My 2nd IF trans was replaced and its destroying my signal transfer. can any 460khz if trans work?

[Radioroslyn]

The 660 2nd IF transformer is unique in that it's triple tuned where most are double tuned. This is used to sharpen the selectivity. As for using a replacement you can probably retune a 455kc can up to 460kc or grab a 460kc can. The only caveat is that it needs to be either an input or interstage transformer not the output. It's designed to match a low impedance diode load not a high impedance grid. Will it work as good as the original probably not. 

https://philcoradio.com/library/download...%20223.pdf

ps Service note the local oscillator adjustment for the bc band and the pol band are reversed to the chassis pictorial. Drove me nutz for a long time as I couldn't get the top end of the bcb to align because I was adjusting the pol band trimmer.

[MICHAEL CHAMBERIS]

Thanks, Still chasing demons in the chassis. about to shelve it and move on but my OCD wants it to work. still looking for another chassis for parts but if a 455 will work it makes it easier.

[MICHAEL CHAMBERIS]

Apon further investigation, The replacement trans is 30 ohms per coil, cap #51 under chassis is missing.

[DaleHCook]

The resistance of a transformer, choke, or coil winding is useful for telling if a winding is open, shorted, or partly shorted. Other than that it is of limited usefulness.

[MICHAEL CHAMBERIS]

I mentioned coil res because on the print its listed as 3 ohms per coil. and the input trans has 30 ohm coils. Thought it might help determine it as a primary not secondary.

[DaleHCook]

Those resistances are only for troubleshooting. They need bear no direct relationship to parts values or configuration, and are likely useless for finding a replacement part. Back in the day radio repair shops could measure resistances, but not RF or IF coil or transformer winding inductances at operating frequencies.