Rock-Ola 1493 - 220 Volt, 50 Cycle In USA

Hi,
I have a Rock-Ola Princess that was built for export. The power supply has a selector switch 220V/240V. The seller said a returning American soldier bought it and had it shipped home to USA. It is a planned gift for our nephew but I will need to restore it first and get the electrical system back to 120Volts..

What is the best way to get this back to 120 Volt operation? I can easily shange the fluorescent lighting back to 120 Volts. I have a 120 Volt/50 cycle Tunntable motor to replace the 220V. I have a power supply from a Rock-Ola 404 that I might be able to use the transformer for a replacement for the existing 220v transformer on the 1493 power supply.

Would it be easier to use a "step-up" transformer to provide 220 volts without any electrical modificarions? I would still plan to change the lighting to 120 Volts and probably just add a spring to the turntable shaft to correct the 50 cycle speed problem.

Thank You for reading this!

David (in sunny Arizona)

Hello David!
The best Way is, you take a Step up Transformer. The Light is for 110 Volts also by the Export Machines.
You have only to change the right speed for the Turntable Motor.
Many Greetings from the cold Austria!
Willi!

Turntable motor, amplifier and lighting are normally working on 120V/50Hz, not 220V. So you can simply change the motor and the ballasts to 60Hz versions. However, some operators have modified the lighting to 220V, using 220V/50Hz ballasts and European size fluorescent lamps because they were much cheaper and easier to get here.

Willi and Marc,

Thank You for your information and help. The existing lighting ballasts are 220 volt so I can easily change those and the fluorescent lamps. I already have a replacement turntable motor that is 120V, 60 cycle. I was concerned the original turntable motor might be a 220 volt motor. I am sure the original motor is 50 cycle because it has a spring to enlarge shaft diameter.

I believe all I will need, in addition, is the Step Up transformer. I think a 500 watt step up transformer will do since the machine operating is rated at 250 watts on 220 volts. Perhaps I need a higher wattage step up transformer?

It is really nice to have help from all over the world. Thank You! We all like jukeboxes.

David

Hello David,

if shipping wouldn't be so expensive - I'd be happy to send you a 110 Volt power supply from a US-version 1493 I have here in exchange for your 220 supply

Kind regards - Oliver Stamann

Hi Oliver Stamann,

I would really like to have the US-version instead of a step up transformer. I wonder what it would cost for shipping and customs etc. Those transformers are really heavy; I weighed the 220v power supply and it is right at 15 pounds. I suppose with double box and packing the weight for shipping would be about 17 pounds. If it is not too costly I'll get some pictures. I'll take a look for shipping to Germany. Thank You!!

David

If you've got 220V ballasts, there will be european size lamps inside the jukebox. These are shorter, so you have to undo the complete conversion if you want to use US-size lamps.

Hello David

I think the only difference between the US version and the export version will be the transformer. The transformer in the export version has a primary winding with four connections (0 volts, 117 volts, 220 volts and 240 volts). One wire of the power cord is connected to 0 volts, the other (via the changeover switch) to 220 or 240 Volts. All parts which are normally operated with 117 volts (turntable motor, amplifier and fluorescent lamps) are connected to O volts and 117 volts.

The conversion to 120 volts is easily possible. You remove the wire of the power cord which is connected to the changeover switch and solder it to the 117 volt connection of the transformer. The 117 volt connection should be accessible at the socket for the lighting or the amplifier (not for the turntable, this socket is not always powered). So everything should work, even parts which work at 220 volts (because they were eventually changed).

The only thing to do now, is the rebuilding of the turntable motor to 60 cycles. This is done by removing of the spring from the motor shaft. The spring at Rock-Ola motors for 50 cycles is made of relatively thick wire. The difference of the shaft diameter with and without the spring is therefore quite large. It is possible that you will need a spring made of thin wire for 60 cycles.

Good luck and greetings from Austria - charly49

Hello Charly,
I also thought about that idea but are not expert enough to say if it will work.
I attach a scan of the transformer which feeds the 1493 with the needed voltages. Wouldn't be the secundary voltages be only half if the primary is connected to the 117 Volt tabs? For example 75 Volt ionstead of 150 and 3 Volt instead of 6,3 etc?

Kind regards - Oliver

No, if you connect 120V to the 117V tap of the transformer (don't care about the 3V difference), the secondary voltages will stay the same. If you would connect 120V to the 220V or 240V tap, the secondary voltages would be only half.
You will also have to change the primary fuse as the current will be higher on 120V.

Great - I learned some basics and David can easily make the adaption!

Best regards - Oliver

Hello David

I made a little drawing to show what must be done. As you can see in the schematic, the turntable motor is normally 117 volts. If you actually have a motor for 220 volts, the relay contact is connected in other ways. If necessary, I can still do another drawing for it.

Marc is right, the current will be at 120 V approximately twice as high as at 220 V. Therefore the fuse should be changed to 6A.

@Oliver: This works, because the primary winding works as auto transformer, like a step up / step down transformer.

Many greetings - charly49

The only thing i'm not sure about is the current through the primary winding. I don't know, if it can stand the higher current.

Hi Everyone,

I can only say "Thank You All"! I will need to study the great schematic made by Charly49 to be sure I fully understand. When I first thought about it it seemed to me also that the secondary voltages would be 1/2 the required value. I do worry a bit about the windings and 6 Amp fuse necessary for the increased current. I could keep a real close watch on the power transformer for over heating. I have printed everyone's comments and the schematic. I'll plan to keep a copy with the jukebox at all times so someone in the future will know what has been changed.

The machine will need to be completely taken apart for cleaning. It has been on a open patio for several years and we get terrible zero visibility dust storms during the summer here. I can make these modifications first.

I sincerly do appreciate everyone's assistance. It is very good of you.

David

Hello David

Don't worry about the 6 A fuse. The current is not really that high. The current for 250 watts rated power at 220 volts is 250 / 220 = 1,14 A, at 120 volts it is 250 / 120 = 2,08 A. The fuse must be rated so high because the starting current is much higher than the current in operation.

You can further reduce the current in the transformer. If you replace the ballasts (2 x 20W) and the turntable motor (about 50 W) with a 120 volts version, the power for it needs not to run across the transformer. Of course, the parts must be connected according to the schematic. The power across the transformer decreases to about 160 W. Therefore decreases as well the current in the primary winding to about 1.33 A. This is only slightly higher than in the original circuit and should not lead to any problems.

charly49

Hello,

I have added a link for two pictures I have in Photobucket. I hope they work.

I think I am beginning to understand how using the 117V tap on the transformer works in this modification. I can also move the lighting to a separate 117V receptacle as the the 1950's Seeburgs have it. I will get the lighting ballasts and lamps for 117V operation.

When I received this machine there was a standard USA type line cord going to the power supply. It is soldered to the cabunet light receptacle and a 3 amp fuse. The USA green ground wire was just taped and not soldered to anything. When I saw the cord I never gave any thought to it. I just cut it off and left the ends shown in the picture attached. The person I bought it from said this machine had worked and played when returned to the USA from Germany. I did not believe his statement. The 220 volt line cord was still in place but the plug had been completely taped up as if to make it disabled. He was probably correct that it did work?

The white wire from the 220V cord stops at the first receptacle shown in the other picture. It should continue on according to the schematic. Perhaps I am missing something?

Thank You All Again!

David

[i1133.photobucket.com]

[i1133.photobucket.com]

Hello David

It is possible that it worked with the extra line cord. You should still remove it completely and use the original power cable. Of course you have to install a U.S. power plug and connect it according to my schematic.

Obviously, the wire colors are reversed in comparison to the schematic. The white wire goes to the socket to which the line switch should be plugged. The switch is normally mounted on the back of the jukebox. I don't know whether he exists or if he is missing. If he is missing, the socket contacts must be shorted.

It seems as if some things have changed. The circuit should therefore carefully compared with the schematic and, if necessary corrected. If you do not have the necessary knowledge, you should look for someone who has it. The work on the power supply can be dangerous.

There are receptacles on the power supply for the fluorescent lights and the turntable motor. You should use them to connect the parts mentioned. The lamps need not to be replaced, they are the same for 120 volt or 220 volt. Different are only the ballasts and starters.

I hope this will help you.

charly49

Hello David,

look here.....


[www.ebay.com]


Best Reguards Ralf

Hi Ralf,

Thank You very much for thr Ebay tip. I saw those and I know Butterfield. I probably should go that way. One unit has been submerged in a flood. The other looks very good. The jukebox is intended as a gift to a nephew who has been asking for one many years. I want it to be safe. As Charly49 pointed out the line cord is not installed in the 220V power supply as the schematic shows. That really bothers me that other things may not match the schematic. The soldering on the power cord appears to me to be from the factory but I am not so smart on all this stuff. I am more of a capacitor/resistor/rectifier/etc. changer and if it does not work I have to get help.

I used a fused Variac to safely test the 220/240V transformer in the power supply I have. All sections of that transformer are working properly. Now I am stuck between just getting a step-up transformer and buying Bill's power supplies. I also have a 404 Capri power supply, with transformer, that probably could be made to work but I am unsure I have the smarts to do that.

Years ago I bought a Rock-Ola 1432 amplifier that came from an old jukebox someone fished out of the Missouri River during a flood. I was really surprised to find it worked very well after changing the capacitors. That amp had been drying out for years so that did it, I suppose.

Thank You! I appreciate it!

David