I have a Philco 37-89 and the RF coil was shorted out so I did the best I could to deconstruct and keep track of windings. As you know....difficult.
I then rewound the coil and installed. The set has been completely recapped and 90% of resistors have been replaced. Reception is strong attached to long wire.
The issue is that the low end of the dial below 640 is missing but I do get repeats of a couple high frequency stations below 640. The tracking on the high end of the dial is good with slight difference to low end Ie; 640 comes in at 690. The set has been realigned.
The question is: Would it be probable that the coil count on the rewound RF be too few turns. (This coil also has a center tap.)
Thanks for any info.
Scott

Sounds like the coil is light in the number of total turns. Presumably you used exactly the same gauge of wire as the original when you re-wound it. If not, all bets are off. However, the coil's overall physical attributes have something to do with it, too- you were probably unable to exactly duplicate the machine-wound original coil with respect to finished overall dimensions. So, there will be interaction between the coil shape and turns count.

Does the SW band function OK?

Thanks CV. The shortwave reception works but I have not taken time to evaluate whether it tracks OK.
In regards to the rewound coil, yes the wire size was as close to original as I could make it. I am wondering now if I should add turns before or after the center tap. Does the bottom of the coil drive the accuracy of the low frequencies or will increasing the turns on the top and bottom of the coil improve lower frequencies? As to coil size...good point. I was very particular about placement and relationship to how and where it was wound but very hard to duplicate.

:Thanks CV. The shortwave reception works but I have not taken time to evaluate whether it tracks OK.
:In regards to the rewound coil, yes the wire size was as close to original as I could make it. I am wondering now if I should add turns before or after the center tap. Does the bottom of the coil drive the accuracy of the low frequencies or will increasing the turns on the top and bottom of the coil improve lower frequencies? As to coil size...good point. I was very particular about placement and relationship to how and where it was wound but very hard to duplicate.

The way this coil does "double duty" is to use only part of the coil for the shortwave band, with the rest of the coil being switched in for the standard broadcast band, which is a lower frequency than shortwave. So, you will need to add turns to the part of the coil that is switched in for BC, not the part that is used for SW.

At this (relatively low) frequency, the coil can be viewed as a monolithic circuit element- different physical zones of it don't correlate to a given frequency span. You should be able to stretch the lower frequency range by just adding windings without regard to exact placement. However, this will be mostly a trial-and-error proposition.

OK, I will see what I can do. Thanks again for knowledge.