The Fine Things are Always Hand Made
I've recapped my dial pointer Philly and it plays good on all bands, but I have a few nagging issues that I would like to take care of before I start the alignment. I want to make sure these are real problems and not "operator error".
1. When I rotate the sensitivity control I get increasing gain as expected, but there is a very narrow spot just off the CCW position that increases gain to the max. I've shot the pot with cleaner but no change. I assume this is not normal, correct?
2. When I turn the expander control on, the expander eye tube opens up indicating maximum expansion but I can't hear any difference. Once I turn the expander on, the eye tube remains open no matter what other actions I take (tune off station, rotate the expander pot, rotate the selectivity control, etc.) I've rechecked the expander wiring and all looks fine. How is this feature supposed to work and is there a good way to test it?
3. Every once in a while, the set seems to almost want to go into an oscillation, but it doesn't. Not sure what this means.
Tomorrow I am going to recheck all supply and tube voltages. Any other ideas on problems 1-3 above?
My pointer stationized dial close-ups - hard to discern, but note the small vernier pointer reaches just into the inner vernier scale tic marks. Also note the size of my pointer, which would not reach the dial broadcast band of the standard pointer dial.
Note also that my upper scale has 4 divisions. and they do not line up with the lower 3 scales divisions. On the standard dial, the 3 upper and 3 lower scale divisions do line up. Now, consider the dial lamp complications.
My 4 th upper stationized scale has its own dial lamp traveling above the Broadcast band lamp. The dial mask has holes aligned with the Chicago station frequencies as of 1937 (and also WLW Cincinnati). So the top dial lamp peaks through only when on a Chicago station frequency. The station call letters are printed on the glass above or below the little circle printed on the glass dial on the 4th band above the broadcast band.
So, evidently Scott had at least 4 dial masks for the pointer model for the respective glass dials: the 6 band standard, and for the 3 stationized versions I am aware of: West coast, East coast and Chicago. Maybe the the stationized masks are actually applied to the back side of the green plastic backer which means 4 version of the green backer. And 2 versions of rotating disk that carries the 3 (or 4) dial lamps for the top half of the dial. That is some restoration complication!
No wonder Scott changed to the Beam of Light Stradivarius dial in 1938.