03-03-2014, 02:46 PM
Ron,
If it's like a lot of other MPX sections in receivers of this age, if the bulb dies (and that IS a major probability), the MPX circuit stops working, as the bulb is in circuit with an active part of the decoder. Also, IIRC, those were very picky as to the lamp properties, you pretty much need to have the exact voltage and current ratings. You may be able to sub in a 6 or 12V lamp for testing purposes, but it's not likely to work totally right.
If it's like a lot of other MPX sections in receivers of this age, if the bulb dies (and that IS a major probability), the MPX circuit stops working, as the bulb is in circuit with an active part of the decoder. Also, IIRC, those were very picky as to the lamp properties, you pretty much need to have the exact voltage and current ratings. You may be able to sub in a 6 or 12V lamp for testing purposes, but it's not likely to work totally right.
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