QuestionQUESTION: I bought a Pioneer pl780 turntable from a thrift store It had the cartridge and needle intact and the platter and everything else worked but I was unable to test it with an album,When I got home and hooked it up to my stereo I got no sound from the left channel.I saw the rca plug was loose so I cut it off and temporarily spliced a jack from another audio cable.I noticed there is a pair of stranded wires on the interconnects one bare the other with foam insulation around it,what is the proper way to splice the rca plug? No matter what combination I try the left channel still doesn't work,I also checked all connections under the table where the wires for the RCA jacks connect and the connections to the tonearm and everything is fine My stereo is fine because other sources work properly,so what can be the problem? Hopefully you can help.I only paid $6 for the turntable.Is this a unit worth paying a shop to repair if I can't figure it out?
ANSWER: The inner conductor of the shielded cable goes to the center pin of the RCA cable. The shield goes to the casing which is the ring of the RCA connector.
There are several connections in the signal chain from the stylus to the RCA cables. There is the cartridge pins, the head shell lugs, and the tonearm pins. One test you can perform is to carefully (using a paper clip) touch the four pins of the tonearm with the head shell removed. Slowly turn the volume up until you can hear an hum. Check each speaker (left & right). If you can hear a hum from each speaker after you touch the pin associated with that channel, it means that the problem is probably in the head shell, connection to the cartridge, the cartridge itself or the stylus may be defective or not seated properly in the cartridge.
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QUESTION: Thanks for your fast response.What I did.let me explain more carefully since the Rca plug was already broken,I cut the cable and cut a 8 inch or so length from another audio cable with the Rca plug still Attached and simply spliced the outer shields together from the 2 cables and the inner shields together,so is that a legitimate fix for now? Now as far as the cartridge it is a P mount type all of the pins are easily making contact,Do I have to disassemble the tonearm to check the head shell connections and how do I do that? Can any internal components like a loose capacitor or resistor cause this or is it definitely the things you mentioned.Do you think this is a decent turntable worth fixing if I can't figure it out?
ANSWER: New, the turntable is only $100. Frankly speaking what is considered good for a turntable costs about 4 to 5 times that, not including stylus or cartridge. If it a simple task to troubleshoot the turntable then it's worth the time, providing you are not expecting exemplary sound reproduction. If the P mount cartridge is connected to the tonearm with a knurled thumb screw, then remove it and look inside the opening of the tonearm and you will see 4 round spring connections that press against the pins of the P mount when you screw it back in. To do further troubleshooting you would need a VOM (volt ohm meter) and you would need some technical skills. There should be no user serviceable electronic components in the turntable. As long as your pre-amplifier (with phono input) works on other sources then you will have confirmed the pre-amp operation
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QUESTION: Thanks,again,I spotted the problem,Obviously I need to go to Radio Shack and buy a soldered phono plug connector because I figured let me splice the RCA jack back onto the cable that I cut it off of and try the cable with my FM tuner,now that only works on the right side so I guess I am connecting the shields incorrectly,hopefully the connector that I buy will have instructions,I have a pen type soldering gun so I will put a new connector on and that ought to solve the problem.I wish these units had just the phono jacks like a CD player so you can choose your own cable.I realize good tables cost over $400 by quality makers like Rega and Music Hall I have seen cartridges costing $400 !and I am slowly treading back into vinyl so right now I am not sure if I have a collection worth investing in a good turntable.I am seeing albums dirt cheap at yard sales and thrift stores usually $1 but the problem is if they haven't been cared for no matter how good the turntable is they will have noise so I inspect anything I buy for as few scratches as possible,Also I realize if the turntable is of poor quality it will wear the record faster.One more question .Does a belt drive vs direct drive turntable,like the one I have has any advantage over one another.What is the sonic difference,if any?
AnswerWhen you get it running here is some advise. Vinyl has a long recovery time. Meaning that if you play it once it should not be played again for, sometimes days or else you permanently lose high end with each playing. It is always a good idea to transfer vinyl to another media (IE: tape, CD, Computer,etc). Before playing a record you should use mild dish soap and wash it with lukewarm water and the either air dry it or use a lint free soft cloth.
