Question for Joe or builders with appropriate test equipment.

George S.

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#61
You have a rare PL2000 Series II factory export wired for 220V. I don't think the folks at PL offered (or contemplated) the PL2000 Series I would ever be exported, so I don't think that they made the Series I for 220V.
That small transformer (T1) has a dual 120V/220V primary. Clearly, the cable is a three-wire and to be in compliance with most 240V countries, the earth (green) wire is securely connected to the chassis. You can buy a 120V to 240V step up transformer and keep your preamp original, or you could convert it back to USA specs. Just don't plug it in to 120V, it will not be happy. Based on the zip-tied cloth covered wiring, I would say it is still factory wired for 220V operation.
Pretty sure about this, but I would measure to be safe: One primary winding is Brown and Brown w/ Yellow stripe, the other primary winding is Blue and Blue w/ Yellow stripe. You have the Brown w/ Yellow stripe and Blue connected together and the one wire of the AC voltage going to Brown and the other wire of AC voltage going to Blue w/ Yellow stripe which places the windings in series for 220V operation. To convert it to 120V operation the primary windings need to be in parallel. When transformer primary windings are connected in parallel, the phase must be correctly observed or the transformer will become damaged. To do this properly, you would connect one wire of the AC to both Brown and Blue twisted together and the other AC wire to both Brown w/ Yellow stripe and Blue w/ Yellow stripe twisted together. This is a standard PL convention, I have wired PL700 Series II amplifiers for dual voltage operation and that is how it's done.
Personally, I would install a 'dual voltage' switch after the fuse and make the primary voltage selectable. You would need to drill two small 1/8" holes and a small 'window' to mount the switch inside the unit. I can send you the switch and the instructions how to wire it in, if you desire.
Thanks for the offer on the switch but doubt this will ever leave the US. Here are some photos, 14 vac from the two output legs (red wires), 7 vac from each leg to ground. Pretty sure my 400 series 2 trans was wired similiar like the solid blue and yellow black joined with the insulating fabric tube and zip ties. I'll look for a photo. It is also a export model, but then weren't all the series 2s? PXL_20201130_150746352.jpg PXL_20201130_150642195.jpg PXL_20201130_150502464.jpg PXL_20201130_150306603.jpg
 

George S.

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#62
You are correct about the wiring after looking at the photo of the 400 series 2. Going to sit down and get this figured out, then fix it. Been wanting to replace that old wire anyhow. You made a great catch seeing this!!! thumbnail (1).jpg
 

Gepetto

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#63
All S2 amps had dual primary construction. Not sure on the preamps, have to look at the service manual.
 

mlucitt

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#64
I'm not advocating for dual voltage so that you can take it out of the country. Having dual voltage retains the original transformer, and gives the ability to maintain the original design of the export model". In other words, the best of both worlds without rewiring in case you want to restore it to original specs.
 

George S.

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#65
So this is where I'm at. 34 vac across the two output legs, and 17 vac between each leg(red wire) and ground(black wire). Not going to hook this up to the board until I can verify those voltages are correct. I saw a post where it was stated the 2000 has + and - 17 volts per the schematic, but I just don't see voltages shown anywhere. Going to look again. thumbnail (3).jpg thumbnail (5).jpg
 

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George S.

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#66
Success. Found a post that I could deduce from that those voltages were correct. Put it back together and into system, LED is brighter and power switch now makes a slight thump. So it was wired for 220 volts with a 110 cord for the 30 odd years I've had it. Crazy!!! Always thought it worked quite well until recently. Thanks for your help (I think "Mark", please correct me if I'm wrong). Best forum ever!!! thumbnail (6).jpg thumbnail (7).jpg
 

George S.

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#67
So is the black wire coming out of the transformer called the "center tap"? What is the correct name for the two red wires?
 

Gepetto

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#68
Yes it is the center tap, the ends are called the ends of the secondary. In this case, you have only one secondary.

So they are Secondary 1 end 1, Secondary 1 center tap, Secondary 1 end 2
 

mlucitt

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#69
Your voltages are now correct and it is amazing that it worked at all at half voltage. The OPAMPs do have a wide voltage range, but you were probably not getting full volume levels coming from the outputs. Your rewiring work looks very good. I would lift the wiring in the area of the repair as far from the circuit board as possible, maybe you could tie-wrap it up to the fuse holder next time you are in there.
 

George S.

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#70
Your voltages are now correct and it is amazing that it worked at all at half voltage. The OPAMPs do have a wide voltage range, but you were probably not getting full volume levels coming from the outputs. Your rewiring work looks very good. I would lift the wiring in the area of the repair as far from the circuit board as possible, maybe you could tie-wrap it up to the fuse holder next time you are in there.
Will do, need to go back in and replace the balance control wiring and some other wiring, then deflux the board. Thank you all, and Joe, the meter kits arrived today. Thanks.
 
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