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I found a Philips radio/record player from I believe 1968 at a garage sale. I picked it up for $5. Sweet deal for me! I researched the cabinet to find it's general manufactured time frame. I've already repaired the record player but the radio is somewhat dysfunctional. Dysfunctional in that only the left side of the unit has sound while the right does not. I checked the speakers, and the balance selection knob works. I then started looking over the PCB board for burnt out components to which I found two ceramic cylinder type components that look like resistors. I thought maybe they were capacitors, but I'm really not sure. They have "M1" stamped on them (i'll attach a photo) and a diagram that looks like an AC voltage source diagram. Circle with a squiggly line throw the middle. enter image description here

I'm not too familiar with components, just getting started with this radio cabinet. I'd like to replace these but I don't know what they are exactly?

Any help would be greatly appreciated. If any further pictures are required I'd be more then happy to upload. Thanks

Edit: Thanks Sparky256, no I haven't tried an ohmmeter as of yet. user2943160: I'll attach some photos for location.

[enter image description here

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  • \$\begingroup\$ Welcome to EE.SE. Have you tried using an ohmmeter, or a capacitance meter? Looks like the part information burned or wore off. "M" is a designator for MOV, but given the age of this part "M" probably has nothing to do with its function. Unless someone knows it by heart, only a diagram or LCR meter could solve this issue. \$\endgroup\$ – Sparky256 Jul 31 '16 at 2:31
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    \$\begingroup\$ Where in the circuit was this component removed from? The context will likely help identify the part. \$\endgroup\$ – user2943160 Jul 31 '16 at 3:15
  • \$\begingroup\$ Your photo shows a silkscreened printed wiring board; what was the designation on that board next to the mystery component? R is for resistors, C for capacitors, D for diodes, Q for transistors, etc. \$\endgroup\$ – Whit3rd Jul 31 '16 at 5:42
  • \$\begingroup\$ Whit3rd, the prints are R344, R346. So, these are resistors. I've looked on the other two components that are identical to the burnt ones, which are to the left in the photo and the only markings are the "M1" and the circle with the wavy line through them. There are no other markings to indicate what type of resistor these are. \$\endgroup\$ – Mike Killingbeck Jul 31 '16 at 6:26
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    \$\begingroup\$ Given their proximity to the power transistors, I would bet that they are emitter ballast resistors for the audio output stage. As such, they would be low-value, high current resistors -- something on the order of 1 ohm and several watts. \$\endgroup\$ – Dave Tweed Jul 31 '16 at 11:35

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