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is this just kookythinking or would it work ?if i remember right......... a pivoting arm is pulled to the center but a linear arm is pulled to the outside.
could the antiskate for the linear be as simple as tilting the entire tt/tonearm ?
im thinking then the stylus would behave as if it were going through a perfectly straight path with no lateral forces other than the information in the vinyl.
if it would work then how would you measure the amount of force:tilt ?
test record ?
i wonder if it would be enough to cause weird bearing wear on the spindle ?
Follow Ups:
There seems to be a little confusion here about which direction anti-skate works in.How about a little experiment.
Set the antiskate control on you arm to 0.
Then set the Tracking froce to zero (i.e., the arm is free floating)
Next, turn the antiskate control to a non- zero value. I believe you will find that the arm moves toward the arm-rest, not to the center of the table. This suggests to me that, when playing a record, the force due to the rotation of the turntable, is pulling the arm/cart toward the centre, and the anti-skate is adjusted to provide an equal and opposite force by pulling in the opposite direction.
Or am I missing something here???
Cheerswelly
I went to a restaurant that serves "breakfast at any time". So I ordered French Toast during the Renaissance.
centrifugal force on the stylus ?
Or maybe you meant something else?
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anything resting on the platter/record would be slung to the outside once the platter/record starts moving.like playing on a playground turntable where you have to run along side the platter to get it going then you jump on it.
if you dont hang on you will be flung off.
seems that the reasonthe stylus doesnt get slung off is from its pressure and the side force of the outer sidewall of the groove.
im thinking that if there wasnt enought stylus downward force the stylus would get slung off.
maybe im just not thinking it correctly.
centrifugal force : the apparent force that is felt by an object moving in a curved path that acts outwardly away from the center of rotation.
i know the stylus isnt moving but it is following a curved path that --is-- moving.
or maybe the stylus --sees-- just a straight path because the curvature at the contact points is so small ?
Skating is where the stylus is pulled towards the center of the record. This is caused by a difference in friction between the inner and outer groove walls. Thus an inward momentum is imparted by the LP's center-spiraling groove on the pivoting tonearm. An anti-skate mechanism counterbalances this force. The force will vary depending on the stylus' distance from center (radius) and the tracking force.For linear tracking tonearms, a non-pivoting arm rides a perpendicular path to the grooves in the record. Because the arm isn't pivoting on an interesecting radius, there's no difference in friction between inner and outer groove walls. Therefore, linear tracking tonearms are not subject to skating.
See the link below for a brief explanation of the physics at work.
grailer ""
This is caused by a difference in friction between the inner and outer groove walls. ""If you read your rather excellent link, the pull towards the center is caused by the vector of the groove wall friction pulling the stylus. Pulling the tone arm inward causes a difference in wall force between inner and outer, hence a difference in friction on the outer and inner wall.
And while that vector (centripetal force) isn't exactly perpendicular to the groove on pivoted arms, it is on linear tracking arms, hence no need for anti-skate.
I do not believe the term centripital (sp?) is applicable here. That term applies to the forces due to a change in direction of velocity.. The stylus isn't doing that to a great degree.I believe the only force needed on a tangential tonearm would be the force required to move the pivot point back and forth. Well, that and tracking force..
Your link was nice. The use of a double modulated groove to set the skate is great, but I never used it. Back in '78, I spun tables in a disco, so had several discs with a blank B side to use to set the antiskate..I knew at the time, that the actual coefficient of friction of the stylus tip on a flat surface was not the same as a hugely modulated groove, but hey, it was close enough for a club full of drunks..
The only problem with antiskating I ran into was due to scratching....when you pull the record backwards, the stylus force adds to the antiskate. Some stylii/tonearm combo's actually resonated horizontally at close to scratching speeds, making the needle pop the groove. So, might as well drop the antiskate to zero, and pop the tracking up to 5 or 6 grams..
Oh, what I used to do to the vinyl...sigh..(but the babes were great).
Cheers, John
Anti-skate is intended to stop the tone arm from "skating" if the turntable is bumped. Skating is when the tone arm bounces across the record, properly set the tone arm should land back in the same grove. Linear tracking designs did not really need anti-skate because the tone arm was not free moving, so it would not "skate" across the record if it was bumped.As I recall there were very few true linear tracking turntables, at least in the consumer market. The majority of turntables called linear tracking really just incremental tracking. As the stylus end of the tone arm would move towards the center it would activate an optical sensor and the base would catch up to it.
tweeneng: ""
Anti-skate is intended to stop the tone arm from "skating" if the turntable is bumped""Not actually. If you read the link posted by grailer, anti-skating is the counterbalance force applied to the tonearm to the offset the side force on the tonearm caused by the stylus to groove contact friction.
When a stylus has lost contact with the groove, there is no skating force at all. At that time when the stylus is not in contact, the antiskate will attempt to pull the tonearm outward.
In practice, any bump capable of pulling the stylus out of the groove will cause the tonearm to go wherever the impulse sends it without regard to the setting of the antiskate. Never in my life have I seen a bumped stylus go back into the location of the groove it was origionally in...If only... I've only seen the tonearm end up on the label, or off the platter and on the base. (and never, ever, did the tonearm land on it's rest..saving the needle..)
Cheers, John
"Skating is when the tone arm bounces across the record, properly set the tone arm should land back in the same grove."That is caused by the lateral balance weight being set wrong.
Some of he lower priced linear tracking tables are/were incremental. But arms like the Souther, the ET, the Air Tangent, the Mapleknoll work with essentially a zero friction bearing and don't need any additional compensation.
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