Cartridge set up in headshell

[Canetoad]

I have a Jelco SA-750 tonearm on my SL1210 and was wondering if I can still use the Technics tool to set the cartridge in the headshell? After all, it is quite a simple and elegant solution. :)

[Tarzan]

I have a Jelco SA-750 tonearm on my SL1210 and was wondering if I can still use the Technics tool to set the cartridge in the headshell? After all, it is quite a simple and elegant solution. :)

l believe( though l maybe wrong) that unless you are using the Technics headshell, then you have to modify the Technics set- up tool:scratch:

[Canetoad]

Yes, I have already cut a 2nd groove for the 2nd pin of the Sumiko headshell I was already using on the standard arm.

[Tarzan]

Yes, I have already cut a 2nd groove for the 2nd pin of the Sumiko headshell I was already using on the standard arm.


That was the mod l believe, now l think you are good to go.

[Qwin]

The Jelco has a shorter EL and PtS distance by 1mm. but overhang the same as technics at 15mm. So if the Jelco cartridge connector is not in exactly the same position as the Technics, the cartridge will have a different position in the headshell and the technics gauge will not work.
In other words, for the gauge to work the Jelco arm would have to be exactly 1mm longer than the technics measured from the arm pivot to the connector face which accepts the headshell. (Straight line measurement). ;)

Oops I mean shorter not longer.

[Canetoad]

Cool! Thanks for that. :) I'll try using a protractor and see how far out I am. It still might be a good starting point.

[Qwin]

Ok I have been considering this because measuring the arm is VERY difficult.

:doh:
Here is an easy way of determining if the Technics Gauge will work on your Jelco Arm.

Print out an alignment gauge for your arm that has the arc on it for the 15mm overhang (effective length).

Mount the cartridge and align the stylus to this arc and adjust the angle to match the null points. Remember to make sure it aligns over the whole of the arc, not just one point when the platter/gauge are in one fixed position.

Take off the headshell and mount it in the Technics gauge. The length should align with the gauge. If it does not, the gauge is not suitable for that arm.
Note that both arms have an offset angle of 22 deg, so if the length is right you can use the gauge. :D

[worrasf]

Print out an alignment gauge for your arm that has the arc on it for the 15mm overhang (effective length).

Mount the cartridge and align the stylus to this arc and adjust the angle to match the null points. Remember to make sure it aligns over the whole of the arc, not just one point when the platter/gauge are in one fixed position.

Take off the headshell and mount it in the Technics gauge. The length should align with the gauge. If it does not, the gauge is not suitable for that arm.
Note that both arms have an offset angle of 22 deg, so if the length is right you can use the gauge. :D

Surely if the OP does this he wont need the Technics guage anyway :eyebrows:

Steve

[walpurgis]

You can't assume that the Technics overhang tool would work with other arms, as each arm has its own geometry and any arm other than a Technics will possibly be different, so a separate alignment protractor is the best option.

The online alignment protractor printouts are notorious for printing at slightly wrong dimensions. Some are supplied with a guide telling you how it should measure. I'd suggest using one of these, then you can correct the printout size if need be. There are loads of free ones to choose from.

[Qwin]

Steve, you are absoloutly right. :doh:
But the exercise is to establish whether the gauge can be used for future set ups.
I personaly don't like it, but pleanty of people swear by it, so each to his own. ;)

[worrasf]

the exercise is to establish whether the gauge can be used for future set ups.


Fair enough. As a starting point to get the overhang in the right ball park its not a bad idea.
FWIW (slightly off topic) I have found a custom MINT tractor gives me the most accurate alignement. I've got several carts all mounted in Jelco or Sumiko headshells. Once the first one was correct I then used a pair of dividers set to the distance between stylus tip and back of headshell then used the same distance to "rough in" the next one (no shaky hands allowed at this stage) before using the MINT to get is spot on. Knowing the correct overhang certainly saves a bit of time.

Steve