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volks
21-11-2009, 16:28
Dear All,

I would like to DIY a tonearm interconnect for a Jelco 750D.

It is a 5-DIN (female) plug to 2 RCA plugs ...

I would like to know what is the configuration/sequence of the 5 pins of the DIN plug.

Many thanks.

volks
22-11-2009, 14:15
Anyone ... pls help ;)

Thanks.

DSJR
22-11-2009, 14:52
Not sure if my suggestion would be good enough for an arm like this, but here goes...

Get some Van Damme "Pro-Patch" mic cable. It's flexible, and portrays air and atmosphere well in this application IMO. Add a pair of Neutric phono plugs (either type will do) and an equivalent length of flexible stranded thin gauge black wire for structure earth. A Canare mini-din socket from eBay should finish the parts list, along with some low melting point silver-loaded solder (2 or 3% silver).

Looking at the mini-din socket from the solder side, pin 1 is on the right I believe. if I use the conventional DIN pin layout, then pin 1 is L+, pin 2 (centre) is chassis earth, pin 3 (directly opposite pin 1) is R+, pin 4 (next to pin 1) is L- and pin 5 (next to pin3) is R-.

I hope I have the connections correct - a multi-meter/continuity tester should confirm if I have it right.

The way the mic cable is configured IMO (and the way I have done it) is to use the two inner cores as hot and return for the cartridge. Use of small diameter heat-shrink is great for neatness too. The cable's outer screen is connected to the signal returns at one end only - I used the phono plug end for convenience (and copying the Mission 774 connection ideals). The extra wire going to pin 2 can be used to earth the chassis of the arm and an extra link could be grafted onto this to earth the turntable chassis to this wire (Linn suggested for best safety that the deck should be earthed to the mains of possible, the arm to the deck and the flying earth wire used unless there's an earthing hum loop). many decks have a two core mains cable, and I suggest the deck should be earthed via this wire.

I do hope that someone else can confirm, deny or expand on the above before you start to make this cable. There is a Canare based cable ready made on eBay for under £40 and this isn't a huge amount IMO, bearing in mind that ancient cast-off decades old Linn arm cables fetch more than this.......

Dave Cawley
22-11-2009, 14:52
It's a standard SME connection. The centre pin is ground, can't remember the others. But if you are making a DIY cable, simply do a continuity test through to the headshell?

EDIT: a multi-meter/continuity tester should confirm if I have it right. Exactly!

Dave

Alex_UK
22-11-2009, 16:50
volks - if you could kindly post a brief introduction in the Welcome section and let us know a bit about you, your system, music tastes and where you are from, and importantly your real first name if it isn't really volks (is your surname wagen?) that would be great, thanks!

DSJR
22-11-2009, 17:17
The SME plug is grand, but not at £44 IMO ;) I'm assuming that the OP wants to save some readies :)

In another time and place, I'd have said that Jelco's own cable was a very good price, even at £100, but all this DIY and online supply at "trade" prices, coupled with my own situation, has modified my ideas somewhat, sadly.......

volks
23-11-2009, 08:43
Dear All,

Thanks for the reply ....

Hi Alex_UK ...
Introduction done in the welcome section :)

Hi DSJR ,
Ya, know about the jelco phono cable .... it is actually Mogamim Neglex 2534 cable which is about few dollars/meter.
Hence , I a not too sure about the performance ....

Back to the DIN configuratiuon ...
If I go for the Cardas 5 pin female DIN, what do you think is the config?

Is the following correct?
Looking at the female DIN from the front , the center pin is the ground(this should be on top as you look at it).To your left as you see it is the R- and far left is the R+
To your right as you see it is the L- and far right is the L+


http://www.audusa.co.uk/images/ic-cardas-tonearm.jpg

thanks..

Rare Bird
23-11-2009, 09:07
Dear All,

I would like to DIY a tonearm interconnect for a Jelco 750D.

It is a 5-DIN (female) plug to 2 RCA plugs ...

I would like to know what is the configuration/sequence of the 5 pins of the DIN plug.

Many thanks.

Multimeter with continuity bleep.One meter lead on cartridge lead one meter lead on din socket, you'll soon find what goes where.

Just to help you the general Cartridge colour id are

White...Left channel *L*
Blue...Left channel ground *LG*
Red...Right channel *R*
Green...Right channel ground *RG*

DSJR
23-11-2009, 09:21
Looking at the SOCKET from the front - Pin 1 should be on the far left if conventional DIN wisdom is followed. As said, get a cheapo volt-meter and check the arm for continuity on the male pins under the arm to the cartridge tags on the shell.