BSR TC8L cartridge - UK Vintage Radio Repair and Restoration Discussion Forum

Restoration73 · 27th Jan 2023, 8:37 pm

No such thing you say.
I used to throw dud TC8s in the bin, but I acquired u/s TC8M and TC8H from a forum member, along with a Sonotone 3509 with a defective case. I thought I would have a go replacing the TC8 elements.
I opened up and carefully removed the two ceramic elements from the 3509.
on the TC8s, remove the styli and fixing screws first.
Care must be taken to remove the aluminium rivets from the TC8s, use a
2.5mm drill to remove the lip on the pressed end, mount the body in a vice and use pin or scriber and tap out rivet using a pin hammer. Save at least one rivet to re attach the front V spring later.
With the body in 2 halves, remove the two plates/terminals and polish the metal surfaces - these make contact with the thin foils attached to the new ceramic elements. Carefully remove the stylus support and the sleeve (retain) from the decomposed crystal/foils(dispose). Clean these and the new foils with meths and reassemble. Note the metal plates in the TC8M are smaller than in TC8H.
I replaced the rear rivet with a M1.5 screw and nut.
The front rivet is enough to hold the V spring which is fitted under tension.
Outcome is a mono ceramic cartridge for playing mono 45s and LPs.
I measured 150mV on scope. Easy to add a single triode or transistor to
make up the loss of output.

John10b · 28th Jan 2023, 3:10 pm

I opened one up a TC8M some time ago just to see the construction, I didn’t make any attempt at repairing iit.
John

Restoration73 · 28th Jan 2023, 3:38 pm

Sadly that's too far gone now ! The ceramic needs a thin layer or sleeve to hold in place.

About 40 years back we could get excellent Condor (Japan) TC8 copies from Bandridge.

The repaired version will also play 78s with a higher output. I got the bolt and nut from a
scrap plastic tuning cap - actually looks like a tiny coachbolt.

John10b · 28th Jan 2023, 4:27 pm

Some pictures of your restoration would be interesting.
John

Restoration73 · 28th Jan 2023, 5:22 pm

The main thing is to cleanly remove the rivets without damaging the body.

I used label remover to remove the remnants of the crystal element, The new element has each foil carefully bent over the sleeving to make contact with the inside of the respective plate.
The stylus pad is quite robust and is held in place with a moulded peg.
I usually inspect styli for damage using a microscope and condemn any without
a conical tip.

As shown, they look the same after the treatment, perhaps they should be
labelled. I'm not sure I could repair GC2 or GC8 carts in the same way. I doubt
it would be worth fixing the stereo TC8S as the compliance is not great.

John10b · 28th Jan 2023, 6:41 pm

Thank you, it would have been interesting to have pictures of the process from start to finish. I opened up a Red Chinese Cartridge, purely out of interest, I wonder if you could use the ceramic elements to rebuild other Cartridges?
John

Restoration73 · 28th Jan 2023, 6:54 pm

They do look a bit long but I don't think the dimensions are too critical as long as the
element at the stylus pad end is free to move. The other end with the foils is anchored
with sleeving, but probably silicon rubber sealant would work - use the non-acetic acid
type. Repairing stereo carts is more difficult, especially if the stylus support is damaged.
I had to scrap a working 8T4A as the stylus mount became brittle and disintegrated.
This is a common problem with 9TAs as well. But certainly give it a try.

John10b · 28th Jan 2023, 7:29 pm

I thought you may want to try. Over the years I’ve not had worthwhile results, so I only investigate purely out of interest. The Red Chinese Cartridges give acceptable results particularly considering their price.
John

Edward Huggins · 29th Jan 2023, 1:53 pm

I'm really impressed with these Red Chinese carts. I might have just been very lucky and bought a good batch, but they sound better (with a very "open" sound-stage) in my Garrard SP25 (Mk 2) than the Sonotone 9TA/HC.

Restoration73 · 30th Jan 2023, 11:19 am

Well I only repaired these because of the turnover esthetic that matched a couple of old
players. Any turnunder cart is superior, indeed I have always regarded TC8 etc as being
rather like a chishel. The Ronette copy is similar.
Even 40 years ago I was converting budget music centres to magnetic. In some case
this actually involved moving the mains transformer. It was a living.

27th Jan 2023, 8:37 pm	#1
Restoration73 Nonode Join Date: Jun 2013 Location: Surbiton, SW London, UK. Posts: 2,801	BSR TC8L cartridge No such thing you say. I used to throw dud TC8s in the bin, but I acquired u/s TC8M and TC8H from a forum member, along with a Sonotone 3509 with a defective case. I thought I would have a go replacing the TC8 elements. I opened up and carefully removed the two ceramic elements from the 3509. on the TC8s, remove the styli and fixing screws first. Care must be taken to remove the aluminium rivets from the TC8s, use a 2.5mm drill to remove the lip on the pressed end, mount the body in a vice and use pin or scriber and tap out rivet using a pin hammer. Save at least one rivet to re attach the front V spring later. With the body in 2 halves, remove the two plates/terminals and polish the metal surfaces - these make contact with the thin foils attached to the new ceramic elements. Carefully remove the stylus support and the sleeve (retain) from the decomposed crystal/foils(dispose). Clean these and the new foils with meths and reassemble. Note the metal plates in the TC8M are smaller than in TC8H. I replaced the rear rivet with a M1.5 screw and nut. The front rivet is enough to hold the V spring which is fitted under tension. Outcome is a mono ceramic cartridge for playing mono 45s and LPs. I measured 150mV on scope. Easy to add a single triode or transistor to make up the loss of output.

28th Jan 2023, 3:10 pm	#2
John10b Nonode Join Date: Nov 2016 Location: Aberaeron, Ceredigion, Wales, UK. Posts: 2,884	Re: BSR TC8L cartridge I opened one up a TC8M some time ago just to see the construction, I didn’t make any attempt at repairing iit. John Attached Thumbnails

28th Jan 2023, 3:38 pm	#3
Restoration73 Nonode Join Date: Jun 2013 Location: Surbiton, SW London, UK. Posts: 2,801	Re: BSR TC8L cartridge Sadly that's too far gone now ! The ceramic needs a thin layer or sleeve to hold in place. About 40 years back we could get excellent Condor (Japan) TC8 copies from Bandridge. The repaired version will also play 78s with a higher output. I got the bolt and nut from a scrap plastic tuning cap - actually looks like a tiny coachbolt.

28th Jan 2023, 4:27 pm	#4
John10b Nonode Join Date: Nov 2016 Location: Aberaeron, Ceredigion, Wales, UK. Posts: 2,884	Re: BSR TC8L cartridge Some pictures of your restoration would be interesting. John

28th Jan 2023, 5:22 pm	#5
Restoration73 Nonode Join Date: Jun 2013 Location: Surbiton, SW London, UK. Posts: 2,801	Re: BSR TC8L cartridge The main thing is to cleanly remove the rivets without damaging the body. I used label remover to remove the remnants of the crystal element, The new element has each foil carefully bent over the sleeving to make contact with the inside of the respective plate. The stylus pad is quite robust and is held in place with a moulded peg. I usually inspect styli for damage using a microscope and condemn any without a conical tip. As shown, they look the same after the treatment, perhaps they should be labelled. I'm not sure I could repair GC2 or GC8 carts in the same way. I doubt it would be worth fixing the stereo TC8S as the compliance is not great. Attached Thumbnails

28th Jan 2023, 6:41 pm	#6
John10b Nonode Join Date: Nov 2016 Location: Aberaeron, Ceredigion, Wales, UK. Posts: 2,884	Re: BSR TC8L cartridge Thank you, it would have been interesting to have pictures of the process from start to finish. I opened up a Red Chinese Cartridge, purely out of interest, I wonder if you could use the ceramic elements to rebuild other Cartridges? John Attached Thumbnails

28th Jan 2023, 6:54 pm	#7
Restoration73 Nonode Join Date: Jun 2013 Location: Surbiton, SW London, UK. Posts: 2,801	Re: BSR TC8L cartridge They do look a bit long but I don't think the dimensions are too critical as long as the element at the stylus pad end is free to move. The other end with the foils is anchored with sleeving, but probably silicon rubber sealant would work - use the non-acetic acid type. Repairing stereo carts is more difficult, especially if the stylus support is damaged. I had to scrap a working 8T4A as the stylus mount became brittle and disintegrated. This is a common problem with 9TAs as well. But certainly give it a try.

28th Jan 2023, 7:29 pm	#8
John10b Nonode Join Date: Nov 2016 Location: Aberaeron, Ceredigion, Wales, UK. Posts: 2,884	Re: BSR TC8L cartridge I thought you may want to try. Over the years I’ve not had worthwhile results, so I only investigate purely out of interest. The Red Chinese Cartridges give acceptable results particularly considering their price. John

29th Jan 2023, 1:53 pm	#9
Edward Huggins Dekatron Join Date: Sep 2015 Location: Southwold, Suffolk, UK. Posts: 8,327	Re: BSR TC8L cartridge I'm really impressed with these Red Chinese carts. I might have just been very lucky and bought a good batch, but they sound better (with a very "open" sound-stage) in my Garrard SP25 (Mk 2) than the Sonotone 9TA/HC. __________________ Edward.

30th Jan 2023, 11:19 am	#10
Restoration73 Nonode Join Date: Jun 2013 Location: Surbiton, SW London, UK. Posts: 2,801	Re: BSR TC8L cartridge Well I only repaired these because of the turnover esthetic that matched a couple of old players. Any turnunder cart is superior, indeed I have always regarded TC8 etc as being rather like a chishel. The Ronette copy is similar. Even 40 years ago I was converting budget music centres to magnetic. In some case this actually involved moving the mains transformer. It was a living.