The joys of fault finding.

Thought some may find this interesting. It's an intermittent signal on my turntable that has kept me near my wits end for over a year now. I think I've finally resolved it.

Problem: No signal in right channel.

Solutions after a long time of it oming and going.

1. Tight fit on VDH connect and amp RCA shield damaged the RCA conn on the audiolab pre (no surprise there). So I decided to get some new cables and a phono pre amp.

2. Problem still there. Checked cables. Found a dodgy cable so i resoldered.

3. Problem still there. Rechecked everything, swapped cables, still there.

4. Took pre amp back for check by dealer. All ok.

5. Took turntable to be serviced. Dealer put a new arm tube on my SME free of charge as he thought it was dodgy. Also fitted new cartridge as I originally thought that may be toast.

6. Problem still there. Stripped SME arm. Looked ok. Found that the centre hole to take the signal from the RCA cable was fractionally too wide so the RCA wasn't touching! Crimped connector slightly to make good contact. Reassemble.

7 Problem still there... Continuity checked the arm. Find that the guy who wired it wired the screens of the R & L around the wrong way so I corrected.

8. Problem still there. But now in other speaker!! Did a resistance check down each of the arm tube wires. One of the screens was 100 ohm higher that the other. Re-soldered the offending joint until it was within 4 ohms of the other channel (this actually took a few attempts!).

Problem solved!

Well that took me well over a year after various 'F*ck it I'll just play CD's' moments. But now I am finally listening to vinyl again.

Can I get a high 5?

 

Here you go

 

I discovered last night that the problem is back.

Anybody want to see a classic Mitchell TT destroyed by a mallet? It should be up on Youtube in the coming weeks.

 

Frankly if it were me I'd just send the arm for a rewire by someone who knows what they are doing (as it sounds very likely its had a rewire from someone who doesn't). Audio Origami would be the place I'd start.

I love the Focus One me. The one bit of kit I don't think I could ever sell.

 

Well I'm going to give it another look tonight with a scope and dvm. But it does seem to be down to the arm wiring. Dry joints and things I think. It's only a short section as the SME Series 3 has a hardwired arm tube (which has also been replaced).

I'd consider myself capable of wiring it myself. Can anybody reccomend a supplier for wire?

 

Again. This damn fault has reared it's head.

Can anyone advise on where to get some arm wire? Normal type, no need for silver litz.

Thankyou.

 

No mention in your list of trying a different cartridge - I'd certainly do that before assuming the arm wiring is shot.

Tony.

 

New cartridge was fitted with the new arm tube.

So far it's had a brand new cart, new arm tube, new cables, new phono stage and a new pre-amp and power amp. This fault has sailed through the lot!

I've got some of this if anyone thinks it's suitable for a rewire:
http://uk.farnell.com/jsp/Cable/Single+Wire/displayProduct.jsp?sku=3220588&_requestid=124632

Not sure of wiring specs for the job.

 

It's been a while but last night I fixed it!

Problem was withing the arm carrier. housing had perished internally and contacts weren't mating properly with the arm. It was a fiddly rebuild but it's finally sounding sweet again.

I'd just like to give a plug to 'Collect Radio' who sell SME spares on E-Bay. I picked up a replacement part for £4 inc P&P. If it wasn't for these guys my SIII was looking like a scrapper.