A 100VA variac will do the job nicely, and yes 121 - 125V is the voltage range where I encounter difficulty.
Variacs are usually available on eBay for reasonable money, make sure to get a fully enclosed unit. A meter is a nice touch if reasonably priced.
I would recommend a setting of 115V at the time of highest line voltage.
I use a small toroid configured to buck the line voltage by 8V or so, works fine, small filament transformers in the range of 6.3V to 10V work well.
Variacs are usually available on eBay for reasonable money, make sure to get a fully enclosed unit. A meter is a nice touch if reasonably priced.
I would recommend a setting of 115V at the time of highest line voltage.
I use a small toroid configured to buck the line voltage by 8V or so, works fine, small filament transformers in the range of 6.3V to 10V work well.
You can use an auto-transformer to change your voltage.
take a small toroid (or EI, but not as easily modified) say 115+115:12+12Vac 100VA with dual primaries and dual secondaries.
The maximum continuous secondary current is 100VA/24Vac = 4.1Aac
This when used as an auto-transformer will power equipment upto 4.1Aac, i.e. 115*4.1 ~ 480VA
You could even use a 50VA and get a lower secondary voltage.
115+115:6+6Vac 50VA wired as an auto-transformer would also do upto 480VA.
The auto transformer can be wired to increase, or decrease, your supply voltage. In both arrangements you have the option to not change the voltage.
You can make the switching more complicated to get a fully adjustable auto-transformer that gives decrease and same and increase of voltage. But I don't recommend that at this stage.
I think Kevin is referring to something similar when he said
take a small toroid (or EI, but not as easily modified) say 115+115:12+12Vac 100VA with dual primaries and dual secondaries.
The maximum continuous secondary current is 100VA/24Vac = 4.1Aac
This when used as an auto-transformer will power equipment upto 4.1Aac, i.e. 115*4.1 ~ 480VA
You could even use a 50VA and get a lower secondary voltage.
115+115:6+6Vac 50VA wired as an auto-transformer would also do upto 480VA.
The auto transformer can be wired to increase, or decrease, your supply voltage. In both arrangements you have the option to not change the voltage.
You can make the switching more complicated to get a fully adjustable auto-transformer that gives decrease and same and increase of voltage. But I don't recommend that at this stage.
I think Kevin is referring to something similar when he said
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Any of these look good? http://www.amazon.com/s/ref=sr_gnr_...&keywords=Variac+100va&ie=UTF8&qid=1446405131
I think this is actually more of a problem on 50Hz, as I have at least one that is almost silent, and another which is not terrible. (60Hz here obviously)
http://www.amazon.com/Variac-Variab...8&qid=1446408602&sr=8-1&keywords=Variac+100va
This one would be ok if quiet enough, see previous posts.. Cheap enough to be worth a shot, and you can locate it somewhere remote like a closet as long as it is properly ventilated.
I checked it with 125 Volt mains on the 100-120 tap and speed can still be controlled on 33 and 45 rpm. without changing the magnet.
Difficult to assess at this distance could be spread in motor speed, think it is best to adjust the mains voltage as suggested in previous posts.
Keep playing about as it should work. The old world had voltage between 190 to 270( 95 to 135 V) . It should cope.
Honestly, I've done everything I could to the table at this point. I don't know of any other things I could adjust.
I don't really want to spend the money on the Variac (and on this table in general) if it's not going to work, as I've already spent quite a lot of money on this already.
Yes it will, you don't want to do that. A weak magnet may also result in difficulty with getting the speed right.. I've only seen one magnet that completely demagnetized, but there was no history to help in determining why this might be so. (It was stored off of the TT so I am wondering whether the fact that the magnetic circuit was not completed might not have something to do with it. These magnets are alnico.)
The table will ultimately prove to be worth the trouble if there aren't other issues with it.
Jaap, whose belt are you using on your test 124? As I have noted before the original Thorens belt fitted to the table seems to work better than any of the replacements I have tried thus far. (Schopper being about the next best)
Erocka, If you don't want to spend the money on a variac do you perhaps know someone who could wire up a buck transformer for you? Antek toroids are inexpensive.
Unfortunately, I'm a loner when it comes to audio equipment amongst my friends, let alone any electrical engineering.
I see the point, it was worth asking. I thought it was one fast and one slower. Put a coin on the platter and count the rotations as it passes a pointer. Remember the first pass is zero. The reaction time on a stop watch is usually about the same stop and start, so error is low. See what you get. It might be you have a new pulley of a generic type has been fitted at some time to convert from 50 Hz to 60 Hz. It might be a general spec type. If like Garrard the pulley was from a range of sizes. The TD124 strobew window must be set for 50 or 60 Hz on the stobe. Be aware that the 45 is not exactly correct when on strobe. This below strobe is correct ( markings are elongated/ gap on 45 and 78 ). A stobe can be made using 2 x 74 HC4060 and 3.2768 MHz crytal. A 100 R series resistor to the red LED 10 mm hi-bright. A 7805 regulator and 9 V PP3 battery to power it.
