Counter Weight & Anti Skating! Help Required

[vktarun]

Dear Friends !

I have little knowledge regarding maual Turntable so need your help in Tone Arm setting,[was using earlier Fisher Automatic linear Tracking Turbtable]

Following are the details of the Turntable in question.

Model No: Cosmic Cogram MK II DD
Tone Arm: Jelco
Cartritge : Classic 700

Its a Direct Drive TT with original company fitted Tone Arm and most probably original Company Fitted Cartritge also. I have following query in this regard.

1. What is the recommended Counterweight ? the TT manual says 0 to 3 gms, which is very wide without any practical use ?

2. How to adjust Anti-Skating Force without a Test LP on this TT ?

3. The Counter weight is calibrated only from 0 to 3 gms, If I use a different cartritge which requires say 6 gms then how to do it? Whether I need to turn it 2 times i.e. 3gms+3gms

4. Glad to have Any other suggestion in this regard.

I am posting a few pictures to clarify the Anti-Skating mechanism.

Regards,

Vipin.

 

[sachu888]

Hi you will find most of the Tts with 3 grams of counterweight.Most of the modern carts need tracking force of .75 to 1.5 grams.General rules of setting Anti sket force of the same value of tracking force.
BTW: Nice looking TT with Classic 700 MM cart.Please upgrade current cart like Shure 97xe
Regards,
Sachin

 

[Saket]

With the current cart. I would advise you to track with a weight of about 1.5-2.0 gms.
Also, as Sachu said, the anti-skating should normally be equal to your tacking weight. But if it poses R-L channel imbalance, you can set it audibly on running TT.
About your 3rd question, I am sure that no modern Hi-Fi cartridge would track at 6 Gms. else it would be a perfect recipe to kill the records. So, practically you don't need counterweight more than 3gms and that you have now. Theoretically, to achieve more than 3 gms, you get additional weights like 2 gms/3gms which can be mounted on the headshell to increase the tracking weight. Some manufacturers even provide some weights with their cartridges...but I would repeat that most modern cartridges would track around 1.75 gms perfectly. Extra weights can break the cantilever or damage the suspension and pose permanent damage to your precious vinyls.
I will not be a bad idea to swap this cart with a modern cart like Shure M97XE. Personally I have not used it but most audiophiles swear by it.
Should you have any query, we would be glad to help.
BTW, you have a fantastic table.

Thanks & regards,
Saket

 

[vktarun]

Thanks for your support.

The Anti Sket is not calibarated. As you can see in the picture it is simply a combination of weight, pully, string and grooves where the string can be tied.

Whether 1st groove corresponds to 1gm and 2nd as 2gms and so on?
Regards,

Vipin.

 

[jls001]

1) Set counterweight calibration to zero.

2) Remove anti-skate weight temporarily.

3) Put on stylus protector if you have one. If you don't have a protector, then BE VERY CAREFUL. STYLUS SHOULD NOT HIT OR COLLIDE WITH ANYTHING.

4) Carefully allow the arm to float free. Don't use arm lift.

Now, is the arm tube level and able to float freely and parallel to record surface?

If no, then move the counterweight back and forth (you may have loosen the screw, if any) till you achieve a free and balanced float. Make sure that you move the counterweight without disturbing the zero setting (done in step 1). When moving counterweight, arm must be on arm rest and secured. If at first you don't succeed, as the poem says, "try, try again." Really

Put arm back on arm rest and secure it. Be very careful with the stylus. I can't warn you enough.

5) Carefully turn the counterweight calibration to x grams as needed by the Classic 700. Sorry, I don't know the recommended tracking weight for this cartridge. You will need to find out.

6) Now set the antiskate weight. This must be exactly same as tracking weight. If you put the string at the first notch nearest to the bend, this will be least antiskate weight (principle of leverage) and it would be typically 0.25 or 0.5 gms. From your picture, I can see only four notches. The amount of counterweight force (0 to 3 grams) is usually matched by the antiskate force, so 3 gms must be distributed over 4 notches. This doesn't feel right to me as the jump is too high. Consult the manual for your tonearm. In the meantime, just use the central most notch and you should be good to go.

Play record. It should play without getting stuck or skipping. If it gets stuck, increase antiskate. If it skips, slightly increase tracking force.

Additional adjustment 1: download and print (to scale) Stupid Protractor from vinylengine (using a computer that is directly connected to the internet, and not via a proxy). Use it to adjust your cartridge mounting on the headshell for the two null points. This will reduce your inner groove distortion.

Additional adjustment 2: if your tonearm supports vertical height adjustment, then please adjust it so that when playing a record, the arm is parallel to the record surface.

 

[sachu888]

Hi Tarun,
This is for you http://www.hifivision.com/phono-turntables/27836-how-setup-turntable.html

Regards,
Sachin

 

[murali_n]

Hi,

The correct tracking weight for this cartridge is 1-1.5 gms, I have its Spec sheet will upload it shortly.

N.Murali

 

[vktarun]

Thanks Everybody for the guidance. I really appereciate you willingness to help a novice.:clapping:

Dear Murali ; please upload, that will be of great help.

Regards,

Vipin Kumar Tarun

 

[murali_n]

Hi,

Here is the spec sheet:


N.Murali

 

[Saket]

Great job Murali. Will benefit the users a lot.

 

[vikashal1]

hi 1> balance your tone arm with counter weight in between ur platter and tonearm holder it should float in air , check with a eye view is its in straight line , ( pls don`t forget to remove your cartriage cover ) , 2> once its in line pls keep the tone arm in toneram holder or place were it usually rest , then slow hold the counter weight in one hand and with other hand move the weight marking usually its moveable , to 0 (zero) , 3> pls check if your cartriage is factory fitted , if yes then hold the counter weight and move it along with marking from zero to the recomended weight , it allow the down force 4> for anti skatting , for most factory fitted cartriage it 2 grove or 3rd grove place the thread in grove place a finger on the grove with the thread and let the balance weight in extension rod attached to it it should work

 

[richarde]

I am new here, and wanted to learn more about A/S design and setup.