Brake magnet TD135

[klinge]

Hi again Niels!

Good to have somebody alert like you for help! I sent the guy a mail yesterday to check if he knows for sure that the magnet for the TD124 is the same as for mine TD135. He thinks so like everybody else so I am going to bid on this one. By the way, he lives only 180 km from here.

Have a nice day.
Regards
Klinge

[zwarte-romantiek]

Where you lucky and you finally got your brake?

Niels

[flavio81]

(post erased, i see you need the big magnet not the small one)

[klinge]

Niels: Thanks for asking. Yes I got a magnet from Germany and really cheap too, I was the only bidder. But please read my question to flavio81 below.

Flavio81: Please explain what you mean with the big magnet! I got a magnet for TD124 but the influence on the speed is very little almost neglectible. And I cann´t see any reason for it. Do you mean that there are two different sizes of this magnet? If so, do you know what they measure or where I can get further information? I am really looking forward to an answer from you because this was something new.
Regards
Klinge

[LousyTourist]

I couldn't see the magnet you bought from the ebay ad, but I can tell you the magnet looks like a fairly circular horseshoe magnet.

It really isn't very strong. You are supposed to put a business card between it and the pulley, tighten the screw enough to allow minor adjustments, and go from there. So maybe a millimeter or two gap between the magnet and the pulley.

[klinge]

Hi Lousy Tourist

Thanks, I am glad for any sugestions to help me solving the problem. The shape of my magnet is the right one according to pictures I have seen. And it is not very strong but it still feels ok to me. But I adjust it as close to the pulley as possible with just a thin pease of paper in between when adjusting. But it does not work. I know that the mains frequency determins the motor speed. But since we are talking about a brake not any electronic regulation the power applied to the motor must be of some importance. The motor is designed for 220V maximum and we have 230V. That means that the motor is stronger and more braking power is needed. Am I right and can this be the problem? Since the magnet was missing when I bought the player I guess that the former owner also had some speed problem. Maybe originating from the date when the switching from 220V to 230V took place? Anybody knows?
Regards
Klinge

[zwarte-romantiek]

Hi,

To my knowledge there is only an one-sized magnet - the TD-124 and TD-135 alike.
Never read anything about two different sizes. The TD-135 has only a smaller bearing than a TD-124. For the rest, the motor etc are alike.

See also http://www.theanalogdept.com/eddybrake.htm

Why do you need a more powerful brake. You don't have to make an emergency brack. It just needs to easily slower down the platter. No full stop in 1 sec.
Furthermore, my TD-135 is working fine on 230 volts so I don't see or heard of any problems when switched from 220 to 230.
Just try and enjoy!

Niels

[klinge]

Niels, no I am not looking for any kind of panic brake. The thing is that I cann´t slow it down to the correct speed. It runs just a little too fast no matter what I do. The magnet is now adjusted to 0.15 mm at the inner ends of the magnet which gives 0.25 mm at the outer ends since the magnet doesn´t have a perfect fit to the diameter of the pulley. That is the same gap as described at the page you are refering to. It still runs just about 1 rpm too fast. Very irritating and I don´t have a clue. How much of restoring have you done yourself to your player or you were lucky to get one allready in good shape?
Regards
Klinge

[zwarte-romantiek]

Hi Klinge,

Mine Td-135 was complete and in a nice shape. It was my very first Thorens and like you I did not know what to do. Luckily, I read about HANZE HIFI, a hifi store, which also revise (vintage) THORENS Td-124's. There is a guy Jaap (Tele88 ?????) who does their restoring of TD-124. Jaap did my TD-135 (and TD-184, my second THORENS). The NEAT P48 and the THORENS CADENCE I did my self. Although the CADENCE is a direct drive and I am not able to get her completely silence yet! Still working on that. I am gonna use the CADENCE to play 78 RPM.
I will have to think about your problem. I have no answer right a way. Sorry.
I like the TD-135. Since a couple of months I have hooked it up to a PHILIPS AG9004 tube amp from 1957. The cartridge is a DECCA GOLD and is sounds amazing.
Really!

Niels

[klinge]

Hi Niels

Nice to know that I am not the first one to get lost in the Thorens wilderness. But I will fix it in some way (I put my trust in you experienced Thorens owners).
I have seen quite a few posts by Jaap somewhere.
I am surprised by the number of Thorens older players some of you have. I have seen very few TD 124 for sale in Sweden and they have been quite expensive so it is hard to emagine that the same person by several of them. And for what I know I have never seen any TD 135 but of course I have not been looking for it either.
And you have got hold of a tube amp! I used to work with such things in the 60th and had some myself. But that was when the transistors came very strongly which ment that it was tubes out and semiconductors in as fast as possible. Seems like you have a really good outfit.
If you suddenly at some instance don´t know what to do please give my problem some thoughts. If I find out something myself I´ll let you know.
Klinge

[tele88]

Hello Klinge

Just back from a month holliday I see in your post that you still have a problem with the speed.
As Niels said I do a lot revision work on idler turntables .
In my collection there are about 30 Thorens TD124 ,135 ,134 ,184 ,524 turntables .
Can you tell me if there is a big change in speed with and without the magnet !
The 230 Volt gives sometimes problems and as you correctly mentioned the motor runs faster and gets hotter. we designed a powersupply with 200Volt output because the motor runs on its best !
Do you use a original Thorens belt the one Schopper sells or a replacement ?

Regards

Jaap

[klinge]

Hi Jaap

Nice of you to take an interest just as Niels have done. I was to contact you but summer arrived just from one day to the next. I had to dig up some energy for a new fence which I am working on right now.
It is some impressive collection of turntables you got. And then of course you know everything that can cause a problem I emagine.
Yes I can tell you about the speed. When I bought the tt the magnet was missing and it was running 7% fast. There was 107 revs in three minutes. With the magnet installed and the vane adjusted for minimum brake effect it was almost 105 revs in three minutes. When adjusted for maximum brake effect it was 103 2/3 revs.
The distance magnet-pulley was then 0.15 mm.
It feels like more braking power is needed to slow it down or a lower voltage maybe as you mention. It seems like the motor is too powerful.
I dont know what brand the belt is. It does not say anything on it. It was in the player when bought. Seems pretty old and a little sloppy. I believe it should be tighter but it does not slip. If I just put it down on a ruler it measures 17,8 mm which means a length of 35,6 mm. I don´t know if that says anything it might not be exact enough.
The power supply you have designed, does it give a stable 200V ac or is it something you can adjust as part of the speed control? I cann´t see that I have anything simple to use to lower the voltage to the motor just to test. Maybe I can find a transformer. There is no electrical data what so ever. The sign under the platter as shown in the documentation for the TD 124 doesn´t exist. On the down side of the tt there is a connector that seems to have been put in over here. Or maybe not but it says nät with swedish spelling for net. Red winding are connected to the net. Green wires are connected together being for 220V as it says, yellow wires are for 127V and not connected together and finally black wires are not connected together and it does not say for what purpose they are there.

This is as much I can tell you right now. I am very interested to hear what you have to say about it now when you more.

Regards
Klinge

[tele88]

Hello Klinge
It seems the magnet does his work ,the belt is too long .
The new belt is 15.7cm yours is 17,8 cm probably the motor runs too fast because the slip from the worn belt is not enough .
The speed from the motor depents from the voltage,freq.and the load !
First try a new belt from Schopper ,please not a replacement !!
If you can"t get it send me a pm.
The Thorens motorsupply is a 200 Volt with his own analog50 hz oscillator with very low distorsion and powerstage .
The outputvoltage and freq.can be adjusted and there is a analogvoltmeter on the front.it can be used for 124,135,134 Garrard 301,401,Lenco L75
Best is that when you use this supply you will be surprised that the sound is so much better then without it .
Everthing has to do with the pollution from the mains, I have done measurements where you can see all those noise etc.
But thats another topic.

Regards

Jaap

[tele88]

Hello Klinge
A picture tells more then words !!

Regards

Jaap