[Done] Dumpster find high-end turntable Sony PS-4300 is it worth repairing? - Page 1
Forum section: electronics / repair

author: agent_power
author_rank: Regular Contributor
timestamp: October 27, 2024, 10:47:34 am
content: Hi allI found this turntable next to a dumpster on the road.It turns on and spins (and squeaks a little), but it's missing the counterweight and the automatic mechanism doesn't do anything.The cartridge and needle probably need replacing too and the audio cable is chewed up.Is this too far gone or worth repairing? I see that it's hard to find parts for it. Maybe it would be possible to machine or 3D-print a counterweight, if it doesn't have to be the exact one?

author: Gyro
author_rank: Super Contributor
timestamp: October 27, 2024, 12:57:17 pm
content: It looks as if it was expensive in it's day (~1976). It's direct drive, so the squeaking is a little worrying, maybe dry bearing. Whether the arm bearings are damaged is a bit of a lottery until you can get it to exactly balance and seesaw. You might get away with a new stylus at it probably has a moving magnet cartridge.As far as the counterweight, I don't think you will get anywhere with 3D printing (insufficient mass and attractiveness) unless you could incorporate a little lead slug. A better idea would be to get an aluminium cylinder turned. O rings are a good but basic way of fitting it onto the arm stub, as they would stop it sliding and provide some mechanical decoupling. Looking at images on the web, the original rotated on a coarse screw thread with the usual scale graduations. Best of all would be to go back to the dumpster and try to find the original as it probably fell off!I found an image of the underside, changing the arm cable would be a simple job. You have nothing to lose except time and the danger of disappointment at any stage...

author: BILLPOD
author_rank: Frequent Contributor
timestamp: October 27, 2024, 01:55:11 pm
content: Good Morning Agent_power, The fact you are asking opinions tells me you 'kinda want to'.Also ask yourself what would you do with it if you did rehabilitate it: would you use it or sell it? Myself, I would attack the motor issue and see if you can get rid of the squeaks and see if the speeds of the turntable are correct. Only after those items are taken care of would I attack other problems. If you can't get good spin on the turntable, the other problems are a moot point. That is my opinion.

author: agent_power
author_rank: Regular Contributor
timestamp: October 27, 2024, 07:48:55 pm
content: Quote from: Gyro on October 27, 2024, 12:57:17 pmHi all, thanks for your suggestions. I actually went back to look for it and didn't find anything. It could very well be that it was dumped due to its condition.Yeah I'm mostly afraid of getting a replacement weight and then finding out it was for nothingQuote from: BILLPOD on October 27, 2024, 01:55:11 pmAs I don't have any high-end turntable I would probably really use it myself. It's too ugly to be resold. If I get it spinning smoothly I will pursue further repairs, otherwise I'll probably part it out.Will get back to you with some results

author: agent_power
author_rank: Regular Contributor
timestamp: November 01, 2024, 05:16:59 pm
content: Someone enlighten me, I took the motor apart and it seems to be maintenance free except for this ball at the bottom.Now that I see it I probably didn't even need to take the motor apart.What do clean and lubricate this ball with? It has some sticky grease on it. Do I understand correctly that the shaft doesn't need lube or would some fine oil be ok?Thanks

author: Gyro
author_rank: Super Contributor
timestamp: November 01, 2024, 06:49:56 pm
content: Yes, you normally just lift the platter / sub-platter off the top of the motor. At least you've got a good look at the thrust face that the ball on the bottom of the spindle runs on (that one looks like nylon, some players use lapped and hardened steel, even ceramic).It looks as if there is a reasonable amount of wear, which will cause more the ball surface to thrust face contact, but it shouldn't squeak. Check that is still clearance between the flat end of the shaft and the thrust face (ie. just to ball in contact), just to make sure the platter isn't running too low in the deck.The more likely place for a squeak is the bearing bushes around the sides of the shaft if they are running dry. Look for any scores in the shaft that might indicate abrasive particles embedded in the bearing bushes. Also check for side play in the spindle (wobble at the edge of the patter). The only other potential sources of a squeak would be corrosion on the pole pieces or magnetic swarf on the inside surface of the magnet, rubbing against the pole pieces and possibly, any parts of the auto-return mechanism rubbing against the rotating parts (I'm not clear how this works as I can't see any gear or cam).The spindle bushes probably need some lubrication by now. I would normally suggest oil, but this is likely to run down the spindle and contaminate the plastic compatible grease on the thrust plate, possibly leaking out of the bottom of the motor, around the metal cap. In this case I would suggest a very light smear ofcleanLithium based grease on the surface of the spindle. Also re-distribute the grease on the thrust plate back to the center, where the ball runs.Keep everything scrupulously clean on re-assembly. Go around the inside of the magnet with adhesive tape to collect any magnetic particles, check the pole pieces, clean and lightly lubricate the spindle and re-assemble.

author: agent_power
author_rank: Regular Contributor
timestamp: November 01, 2024, 09:03:51 pm
content: Alright, thanks for the tipsThe old grease was somewhat crusty, I completely removed it and cleaned as per your instruction. Because I don't have Lithium grease I applied some Super Lube "Multi Purpose Synthetic Grease with Syncolon" where the ball rests and a small amount around the bushes.This helped, it doesn't squeak anymore. According to the RPM speed app +/- 0.55% WOWI also sprayed some contact lubricant (lazy I know) around the automatic arm movement which seems to have broken up the old grease enough to make the mechanism do its job again.Now I have the issue of the counterweight, as well as the broken headshell and needle. I will try to borrow a cartdrige from somewhere to check if the sound works, as well as fix the sound output cable.

author: Gyro
author_rank: Super Contributor
timestamp: November 01, 2024, 10:18:02 pm
content: That sounds promising. I didn't suggest changing the thrust pad grease because it is a heavily loaded part and I didn't want to encourage additional wear. If it was crusty anyway though, it was probably doing more harm than good. I think Super Lube (from some oil I have) has pretty good materials compatibility.Those headshells are a standard item. I remember, years ago, ADC used to do a rigid Magnesium aftermarket one (LMG-1) as an improvement to various manufacturers standard ones. ebay should yield many different replacements, far easier than trying to fix it.EDIT: This US listing has a PS-4300 counterweight, you might try asking the seller to weigh it for you!https://www.ebay.com/itm/305866531765. Turned steel shaft collars are plentiful on ebay, if you can find one the right internal diameter (with/without o-rings) and mass, it might be a cheap and reasonably attractive substitute without needing a lathe.

author: agent_power
author_rank: Regular Contributor
timestamp: December 13, 2024, 07:36:42 pm
content: Update to this:After reassembling the motor I lost a nut inside which didn't want to come out (stuck to a magnet). This prompted an almost complete teardown of all the insides at which point I decided to replace the old grease including adding new dampening grease to the tone arm lift. While there I also re-did the audio output cable.I found a cheap cartridge with a good enough needle and rigged some counterweight (roll of solder) to test the player. It worked pretty well therefore I decided to buy a replacement counterweight. They can be found rather cheap on Yahoo Auctions Japan through Buyee, it cost me around 25€ including shipping and even though it was sold as junk it was packed well and looks like new. (you could buy this model record player for 10 bucks in Japan but then would have to figure out shipping)

author: Gyro
author_rank: Super Contributor
timestamp: December 13, 2024, 08:23:28 pm
content: Very nice result. Thanks for reporting back, too few do.