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perpetuum: Anti Skate adjustments?

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Forum » Radios and other type of sets (Physics) etc. » MODELS DISPLAYED » perpetuum: Anti Skate adjustments?
           
Paul E. Pinyot † 2013
Paul E. Pinyot  † 2013
 
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11.Jun.10 22:10

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The tone arm "skates" across the record when the needle touches the record.  I am familiar with anti-skate adjustments on other turn tables.  But after typing some of the instructions into Google Translate I could not find a procedure for this turn table. 

1)  Is there an Anti Skate adjustment? 

2) Does the cam arm the makes the motor turn off hold a spring that compensated Skate?

3) Did I miss some thing on my German to English translation that explains how to adjust for Anti-Skate?

Thank you my German reading/translating friends.

Paul.

Bernhard Nagel
Bernhard Nagel
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12.Jun.10 16:38

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Paul,

due to the (quite simple) construction of this PE record player, there is no provision for a skating force compensating given. Almost all players which work
1. with a crystal pick-up mounted in a
2. non-counterweight balanced tonearm lacks of this feature. So you won't localize such an adjustment here.

If the tonearm skates across the groove(s), several things should be considered for a reason. First, the sapphire needle could be worn out. The tip should be ball-shaped (spherical) if watched through a microscope with at least 50 (better 100x) magnification factor. Second, the rubber support/bearing in the pickup (where the needle tubule is rested) could became hardened so the compliance is lowered too much. Third, any force applied to the tonearm could make them tend to swing towards the center hole of the disc. And last but not least, the tracking force should be in a range from 5...8 grams (depends at the specifications of the pickup).

Hope, this will help you.

Regards,
Bernhard

Paul E. Pinyot † 2013
Paul E. Pinyot  † 2013
 
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12.Jun.10 18:11

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Bernhard,

Thank you for the explanation.  I believe the Sapphire is worn out.  I will look for a supplier for a new needle or a whole cartridge.  I believe there is a procedure for rebuilding cartridges from Syl ( on RM.org). 

I only remaining action is to verify the spring location on the power off cam located on the tone arm shaft. 

Thanks again,

Paul.

Paul E. Pinyot † 2013
Paul E. Pinyot  † 2013
 
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18.Jun.10 03:46

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Bernhard, 

I put a new needle on the cartridge today. It works and does not skate. BUT the output is low. I must turn the volume just about all the way full.
 
Are there replacement cartridges available?
 
Thanks,
Paul

Update:  I ordered this cartridge from ebay #350366946025. $22 dollars shipped domestic.  I will try and change the mounting bracket and install the new and tested cartridge in the unit.  I will report back once I install and test the phono. I also purchased the needle mentioned above for about 5 bucks shipped.

I also adjusted the "turn off" cam.  If it is not bumped or vibrated it will turn off the motor at the proper end of the record.

But I am still not confident it works properly.  There is a weight that applies friction to the cam holding it from advancing relative to the tone arm and engaging the turn off function too soon.

PP.

This article was edited 19.Jun.10 05:20 by Paul E. Pinyot † 2013 .

Bob Timms
Bob Timms
 
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12.Feb.11 18:57

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Hi Paul

Where is the "TURN OFF CAM" ?

Mine is late to shut off. I have to move the arm right to the spindle to get it to turn off.

A photo might help me locate said CAM.

Thank you

Bob Timms

Paul E. Pinyot † 2013
Paul E. Pinyot  † 2013
 
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12.Feb.11 22:58

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The long arm is the start of the turn off mechinism.  it will be pushed by a small spring wrapped around the platter. 

 

I hope this helps. I have more pictures at this link.

Paul.

Bob Timms
Bob Timms
 
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13.Feb.11 00:29

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My PC board the capacitor is mounted on is different than your 4230. There must be different versions.

I adjusted the shut off , by loosening the 2 sloted screws on the coller below the pickup arm.

You then move the arm itself very slightly in the needed direction to increase or decrease the trip point. You do not have to move it very much to gain a big adjustment. Tighten one screw and try. Repeat as necessary. Took about 6 tries for me and now it shuts off excellent.

 

Having a problem getting the motor to run cooler. Need a .12 @ 450 VAC Cap.

Mouser does not list it.

Bob Timms

This article was edited 13.Feb.11 00:31 by Bob Timms .

Paul E. Pinyot † 2013
Paul E. Pinyot  † 2013
 
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13.Feb.11 05:24

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Bob,

Moving the Tone arm on the shaft is how I set the eject point.  It only took you six tries you say? ;~)

I just ordered a variety of caps capable of handling the AC voltage.  See this page here.  They have an AC voltage rating that will handle your ac supply. You may have to parallel a few to get the exact cap value you are looking for.  You should be able to "test drive" your cap selection with the yellow 630v polyester/polypropylene caps for a short time.  Do not leave them in permanently.  Some of those caps can handle a significant AC voltage. But you have to check the specs.

If I recall correctly you need about a 1.1uf cap for that motor. (This motor runs at 160 volts).  I do not have my old collage notes on calculating the cap needed to generate the phase shift for these motors (I wish I kept those old lab notes). 

I do recall reading about the motor cap in other RM.org postings.  Try a search.

Paul

This article was edited 13.Feb.11 05:41 by Paul E. Pinyot † 2013 .

Bob Timms
Bob Timms
 
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13.Feb.11 16:40

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Paul

My Motor runs @ 220 VAC. It is a German Radio not a US import.

I am using the 125 VAC tap to run it The original cap in mine is .15 MF @ 450 VAC

The measured voltage motor running is 213 VAC.

I have tried differnt cap values using 1600 VDC caps

.125 MF works good. Motor runs cooler but not by much.

.133 MF works better as far as starting from a discharged point.

The Temperature  is what I was trying to get to run cooler. Possible Phase shift created in the 2 windings for 50 Hz operation.

END result. I will install a NEW .15 @500 VAC and let it go at that. Think I am being anal on this.

Used the link to Mouser. I have account with them . Like them alot NO min order.

Hopefull I can call it DONE oncew the cap arrives. Great site you have photo's help alot.

Might want to have a photo showing the coller with the 2 slotted screws, used to adjust shutoff limit. I will snap one when I get mine out to install new cap.

Cheers,

Bob T.

  
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