TC8M cartridge conversion. - UK Vintage Radio Repair and Restoration Discussion Forum

lovejoy · 5th Jun 2007, 12:05 pm

I own a 1959 dansette recordplayer which has been converted from its original tc8m cartridge to a 4 pin sc 12h. On close inspection only two wires , are bridged between the four terminals. I have many machines that could do with this conversion but when changing cartridge and bridging the 4 terms with the wires it doesnt work. Does anybody know how to do this conversion sucessfully.

Many thanks

jamesperrett · 5th Jun 2007, 12:50 pm

It has been a little while since I last looked at an sc12 but I thought that it had + and - markings on the back by the pins. As far as I can remember you just connect the + pins together and the - pins together and take wires from them.

Cheers

James.

Tim · 5th Jun 2007, 2:11 pm

James is referring to the phasing. If the cartridge concerned is stereo, you must ensure it is connected correctly or you won't get any(or seriously reduced ) output.
This reminds me of a presenter at Bristol hospital radio, who was "on" the night I was engineering. He told us a strange tale of his home record player that would play some records but not others. We eventualy established Mono records would play and Stereo ones not. The problem was ...........one half of the stereo cartridge connected "backwards", or out of phase with the other.

PWH · 5th Jun 2007, 5:30 pm

I have also connected the + to a - which is a bit like adding two batteries together , you get a higher output and both channels (mono of course) which gives a bit more drive to some amps. The parallel way described above will be preferable if the impedance of the cartridge matches the impedance of the amp.

AndiiT · 5th Jun 2007, 7:22 pm

Hi,
If you are lucky enough to have a unit which has a record deck that is pre-wired for stereo, as many of them are (i.e. four wires running from the pick-up head to the tagstrip underneath the deck instead of two) you can put the "mono-ing" link at the tagstrip instead of at the cartridge end, some cartridges don't take too kindly to a lot of heat from a soldering iron.
Additionally if you ever have to replace the cartridge it makes things a little easier

Regards
Andrew

Tim · 5th Jun 2007, 9:39 pm

Quote:

I have also connected the + to a - which is a bit like adding two batteries together , you get a higher output and both channels (mono of course) which gives a bit more drive to some amps.

One sometimes sees this as a diagonal wire strap between the connecting pins on the rear of the cartridge.

PWH · 18th Jun 2007, 6:27 pm

This link may be of assistance

http://perso.orange.fr/jlf/erepro2.htm

5th Jun 2007, 12:05 pm	#1
lovejoy Retired Dormant Member Join Date: Jun 2007 Location: brighton Posts: 1	TC8M cartridge conversion. I own a 1959 dansette recordplayer which has been converted from its original tc8m cartridge to a 4 pin sc 12h. On close inspection only two wires , are bridged between the four terminals. I have many machines that could do with this conversion but when changing cartridge and bridging the 4 terms with the wires it doesnt work. Does anybody know how to do this conversion sucessfully. Many thanks

5th Jun 2007, 12:50 pm	#2
jamesperrett Octode Join Date: May 2007 Location: Liss, Hampshire, UK. Posts: 1,875	Re: dansette tc8m cartridge conversion It has been a little while since I last looked at an sc12 but I thought that it had + and - markings on the back by the pins. As far as I can remember you just connect the + pins together and the - pins together and take wires from them. Cheers James.

5th Jun 2007, 2:11 pm	#3
Tim Dekatron Join Date: Jan 2003 Location: Bradford on Avon, Wiltshire, UK. Posts: 3,310	Re: dansette tc8m cartridge conversion James is referring to the phasing. If the cartridge concerned is stereo, you must ensure it is connected correctly or you won't get any(or seriously reduced ) output. This reminds me of a presenter at Bristol hospital radio, who was "on" the night I was engineering. He told us a strange tale of his home record player that would play some records but not others. We eventualy established Mono records would play and Stereo ones not. The problem was ...........one half of the stereo cartridge connected "backwards", or out of phase with the other. __________________ "Nothing is as dangerous as being too modern;one is apt to grow old fashioned quite suddenly."

5th Jun 2007, 5:30 pm	#4
PWH Heptode Join Date: Mar 2003 Location: Waiheke Island, New Zealand Posts: 503	Re: dansette tc8m cartridge conversion I have also connected the + to a - which is a bit like adding two batteries together , you get a higher output and both channels (mono of course) which gives a bit more drive to some amps. The parallel way described above will be preferable if the impedance of the cartridge matches the impedance of the amp.

5th Jun 2007, 7:22 pm	#5
AndiiT Octode Join Date: Aug 2005 Location: Saltburn-East, Cleveland, UK. Posts: 1,786	Re: dansette tc8m cartridge conversion Hi, If you are lucky enough to have a unit which has a record deck that is pre-wired for stereo, as many of them are (i.e. four wires running from the pick-up head to the tagstrip underneath the deck instead of two) you can put the "mono-ing" link at the tagstrip instead of at the cartridge end, some cartridges don't take too kindly to a lot of heat from a soldering iron. Additionally if you ever have to replace the cartridge it makes things a little easier Regards Andrew

18th Jun 2007, 6:27 pm	#7
PWH Heptode Join Date: Mar 2003 Location: Waiheke Island, New Zealand Posts: 503	Re: dansette tc8m cartridge conversion This link may be of assistance http://perso.orange.fr/jlf/erepro2.htm