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Old 10-15-2019, 04:22 PM
Phil Phil is offline
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Join Date: Aug 2016
Posts: 147
Sparton 4940

I have one of those. The tuner is an unusual arrangement. It is built like a large series of slide switches, for lack of a better way to describe it. The tune circuits are on a "sled" which slides back and forth when the channel selector is moved. This set has several odd design elements for its time. For one thing it uses a osc./amp to produce the HV. It is independent of the sweep. My experience with those is that they seem to be problematic. I have never had any trouble with the Sparton. It produces a very good picture and is one of my favorite and most watched sets. I'm fairly sure mine does not have channel one and it definitely covers 2-13. I wonder if is possible the one is from 11?
The prop rod holding the lid up would be of some concern to me. It shouldn't be there. One of the nice things about this set is that the lid can be opened to any angle, so it can be adjusted to be viewed at a wide variety of seating heights. The power switch is operated by opening the lid.
This site offers some insight into the circuit: http://members.iinet.net.au/~cool386...n/sparton.html

The biggest issue I had in restoring mine (all electrolytic and paper caps replaced before ever applying power the first time) were bad mica caps and resistors drifting with temperature in the vertical and horizontal oscillators. I think I wound up replacing ever cap and resistor in the oscs before they ever became stable.

I hope you grab it. They are really a very nice set.
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