46-1203 / Low Phono Volume Question
Posts: 4
Threads: 1
Joined: Mar 2014
City: Colorado
Greetings and salutations!
I recently had some friends up in January who happened across an old Philco 46-1203 Turntable / Radio at a Consignment store. To my surprise, they purchased it as a gift for my Fiancee and I, and I can't be more ecstatic about it.
But I have a couple of questions about its operation, and where to start looking. The unit plugs in, turns on, and seems to work great both in Radio and Phonograph mode, with one exception:
When the power/select dial is turned to Radio, the volume levels are normal, and the tuning sounds great. But when the unit is switched to Phono, there is little volume from the playing record, if I turn it half, to all the way up, I can definitely hear the music from the speaker, but it is almost inaubible, and at its highest volume, masked by a HUM that is slightly louder than the actual music.
Does anyone have any advice on where to start with troubleshooting one-sided / phono-only volume issues?
I will have the electronics out soon so that I can refinish the old player's case, and feel that will be a good opportunity to check things out.
Thanks in advance for your input!
Posts: 599
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Joined: Jan 2014
City: Edmonton AB CA
sbish, Welcome to the group! Your record player most likely needs a new or rebuilt cartridge. They used a crystal that goes bad with age. There is an writeup on this site that shows how to do it yourself or do a Google search for a placed called WestTech, they will rebuild them for you.
Gregb
Posts: 599
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Joined: Jan 2014
City: Edmonton AB CA
One more thing, the electronics will need the usual upgrade as well, new caps, resistors as needed and anything else that needs refreshing.
Gregb
Posts: 736
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Joined: Jun 2013
City: Hayward, California
Even though your radio plays, if it hasn't had the paper and wax capacitors changed it is not safe to use. They can start a fire and even if no fire , if one goes out it can make alot moe damage to other parts in the radio. it really shouldnt be played until it has had a recap and gone over electronically.
Posts: 4
Threads: 1
Joined: Mar 2014
City: Colorado
Thanks for the input, folks!
The cartridge in the radio is a Shure W60B, it's been pretty difficult finding a 752-S3 needle for proper playback of the Crosby/Kern 78's I have, so for the moment it has a speed compromise needle (752-S2) - that wouldn't also be part of the problem would it? I've seen the cartridge-rebuild info floating around this forum, and might give it a shot soon. Worst case scenario I just order a new/old cartridge
As for the electronics - when I received the radio, it had a small bag of clipped paper-and-wax components, so I'm assuming someone had already done a little work on it before i received it, but I will double check this when I pull the electronics out to clean up and re-stain the case.
Is there a good write up somewhere on removing the electronics from this model without damaging anything? I'm most worried about the tuning apparatus getting messed up.
Posts: 1,562
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Joined: Nov 2008
City: Sedona, AZ/Placentia/CA
sbish, the fact that you received parts taken out is positive that some did replace caps. Your problem on the phono certainly sounds like a bad cartridge not a bad stylus. There are many new replacement cartridges that may work just fine. I know I worked with a site VM something to ask their expertise on a cartridge that couldn't be rebuilt and bought a new one for very little money. Not the same ancient model. Crystal cartridges age due to moisture.
A fairly simple test if the aspect of the phono input to the amp is working is to set the radio to phono, set the volume at about mid control and raise the phono arm up. With a small bare wire, hold it and touch the cartridge output wires, one at a time. One should give you a very loud hum. If it does, more that likely it is really the cartridge that is weak. If your radio has a plug on the back for the phone, you could also try the test with the plug removed and trying on the socket for the phono on the radio. If an RCA, just touch the wire to the center of the socket. Should get some great hum. Great hum on either indicates the radio is ready for some good output from the cartridge. The cartridge is most likely on its way out if playing low.
Jerry
A friend in need is a pest! Bill Slee ca 1970.
(This post was last modified: 03-08-2014, 09:50 PM by jerryhawthorne.)
Posts: 4
Threads: 1
Joined: Mar 2014
City: Colorado
Hmm, can't say I'm totally clear on that jerryhawthorne. At least with the cartridge (Shure W60B) that's installed now, there's a rubber shroud over the output wires on the underside of the tone arm/cartridge (red / black, the grounding goes to the mesh of the cable) so I can't get at either with any sort of wire without pulling the whole tone-arm off, unscrewing the cartridge, and trying that way (which, let me tell you, I'm bound to try here in about 10 minutes).
Noticed with the volume for the phono, audio does come out of the speaker, but the only thing that gets louder with turning the volume knob is the ac hum/drone, the music itself seems to stay about the same from halfway to full volume!
Posts: 4
Threads: 1
Joined: Mar 2014
City: Colorado
Aha, I took the tone-arm off, so I could get behind it, and ran your test, and sure enough, plenty of hum! So that definitely points at the Catridge then, guess I'm looking at finding someone to rebuild it, or trying to do it myself, though -- being so far up in the mountains, I have no idea where to suss out a donor crystal, aside snooping about online.
Will have to poke around that DIY thread by Syl some more.
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