I recently discovered a new problem with a Gulbransen Rialto K I rebuilt. From what I can gather one of the light dependent resistors may be failing. These are referred to as "ORP-60" on the schematics. I cannot locate this part anywhere - probably long out of production. Does anyone here know if these are still being made, or if not what the equivalent LDR (they now seem to be called "photoresistors") would be? The ORP-60s look similar to modern-day phototransistors (a glass "bulb") but they are not prototransistors. I found an LDR called an ORP-12 but that looks very different than the ORP-60. I cannot locate a spec sheet for the ORP-60. Any information about replacing this part would be greatly appreciated. Thanks.</P>
-jim</P>
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