Unjamming an immaculate Technics SL-5 (with photos)

[Neil Vine]

Hi all, first post! I find myself surprisingly expeled from Vinyl Engine [1] and instead of faking my way back in I've decided to turn a new leaf and start somewhere else.

I bought a Technics SL-5 a few months ago which was advertised as being in perfect working order. This was close to true but I found that on some albums the auto-return would kick in a minute early. I decided to take the motor and tonearm covers off and clean things up a bit with 99% isopropyl alcohol and relube with a silicone-based lubricant. When I returned the covers, I could see that the tonearm would struggle and start skipping halfway across the record.

When I remove the tonearm cover it plays perfectly and no longer auto-returns a minute early.

Two questions:
1. Is it safe to play records with the tonearm cover off? I played on a record I don't care about and it seems fine.
2. Is there some special way to fit this in I'm not understanding? The manual is hard to read and I can't find any videos online.

I've attached some photos. Would love any advice and happy to be a new member!



[1] Really weird situation. I was new to vinyl and enjoying the vinyl engine a lot. I kept a list of small improvements that could be make to the site (like including the date beside reviews) and posted them. The site owner replied but didn't seem himself prioritizing my feedback very highly (which I am totally fine with). I then asked if he was considering allowing archive.org to index the site and the PDFs in the event something were to happen to the site, and I was instantly erased from the site as were all my posts. First time this has ever happened to me and looking at reviews of the site on trustpilot.com I'm certainly not the first.

 

[HPMguy]

Hmm, my SL5 has a new home so I can't check easily, but I think the end of record is a mechanical switch. Make sure the cover isn't getting stuck as the tone-arm carriage moves. Start position is an adjustment of a micro switch through the rear of the cover. You may need to remove the motor cover to get the tone-arm cover back on properly, I don't remember removing it myself. There is a push-pin on the hinge side of the motor cover that has to come out to get the cover off, don't remember if that is in the SM or not.

Mine had a bad belt and needed lubrication, looks like you have already done that. If you have not replaced the drive belt for the the tone-arm carriage, do that, it cures all sorts of ills on these turntables. Some new grease on the worm gear for the carriage works wonders as well (I use synthetic wheel bearing grease).

Replacing all the electrolytic capacitors on the board inside will help quite a bit, note that you need an axial 1000uF 35V capacitor and they getting to be hard to find. Might have to find a way to put a radial in there.

Set the tone arm action correctly as well if you can, requires a DMM. If the gain is incorrect, the computer might "think" it's at the end of the record when it is not, although that's better than dragging the stylus across the disk!

 

[Cactus Bob]

Sorry about the problems with it but immaculate??

 

[Neil Vine]

Sorry about the problems with it but immaculate??

I’ll post more photos but it’s in remarkable shape. Not new old stock but was well cared for. Perhaps even better than never used because it 99% worked.

 

[Neil Vine]

Read the middle part of my post. You missed the plot twist!

 

[gadget73]

Might want to change the drive belt while you're in there. It lives under the cover on the opposite end. Usually it gets stretched and causes strange behavior. If the arm doesn't move with the motor properly, it will just pick the arm up and shut things down. Possibly there is slight extra drag from the cover for some reason, just enough to make the belt slip and cause it to act up.

Can run with the cover off, it won't bother anything besides looking funny.

End of record I *think* is an electronic variation of the velocity trip record changers use. The arm has an angle sensor that is used to bump the arm drive mechanism over to keep it within whatever the range of angle is. The further over the arm goes, the higher the voltage, and the faster the motor goes. Beyond a certain point I expect it triggers the "end of record" sequence because of the much steeper pitch of the lead-out groove, or maybe it relies on the captive groove to show zero movement.

 

[Neil Vine]

Might want to change the drive belt while you're in there. It lives under the cover on the opposite end. Usually it gets stretched and causes strange behavior. If the arm doesn't move with the motor properly, it will just pick the arm up and shut things down. Possibly there is slight extra drag from the cover for some reason, just enough to make the belt slip and cause it to act up

I think the previous owner did that as it was used continuously since the 80s apparently, but I'll keep my eye out for weird behavior.

Can run with the cover off, it won't bother anything besides looking funny.

I guess if I overgreased things it might drip on the platter or an LP? I did not though, so I don't mind. Maybe it will get dustier?

End of record I *think* is an electronic variation of the velocity trip record changers use. The arm has an angle sensor that is used to bump the arm drive mechanism over to keep it within whatever the range of angle is. The further over the arm goes, the higher the voltage, and the faster the motor goes. Beyond a certain point I expect it triggers the "end of record" sequence because of the much steeper pitch of the lead-out groove, or maybe it relies on the captive groove to show zero movement.

Seeing as the issue disappears when the tonearm cover is off, does that change this assessment? I have zero elecromechanical knowledge unfortunately.

 

[Rt8]

I'd be cleaning this bar first if you haven't done already.

To get to all of it,

If you open the lid with power on, press the switch that is triggered by closing the lid and use the long press on the play button to move the tonearm as much towards the spindle as possible, then power off. This gives access to the bit of shaft that is usually covered up by tonearm.
Clean it and re-grease. Check it again.
After this I'd check the belt as mentioned above, if the previous owner said they changed it maybe it's oily and slipping.
I have SL6 which had v similar symptoms and this worked for me.

 

[HPMguy]

If the tone-arm cover isn't fitting correctly it could be jamming toward the center of the record. As I said, I don't have one here anymore to check, but I never took that cover off, just the one over the motor.

I would take the motor cover off, replace the belt, re-lubricate (and you should NOT use a lot of grease, if you think it might drip off you put on way too much) and fit the tone-arm cover first, then the motor cover.

You can also remove the outer cover and get access to all the insides if I remember correctly.