Recommend a 230v 50Hz power transform for use in US?

[lattiboy]

Hey all,

I recently purchased a Marantz PM7200 from our local goodwill. Well, turns out I should read listings as it's the 230v UK version.

I've been looking on Amazon and the options for power transformers are seemingly endless. What would be the cheapest one that will work with this receiver. Here's a picture of the PSU:

 

[g..v]

Get a schematic. It may be that it's possible to rewire the transformer input inside the chassis. Otherwise a stepdown transformer of suitable current capacity will do. Never mind about 50Hz. After all, the transformer feeds a power supply which provides dc to run everything.

 

[lattiboy]

Get a schematic. It may be that it's possible to rewire the transformer input inside the chassis. Otherwise a stepdown transformer of suitable current capacity will do. Never mind about 50Hz. After all, the transformer feeds a power supply which provides dc to run everything.

Thanks. I can't seem to find the maximum wattage the PM 7200 requires. I'm used to seeing that info by the power cord on American electronics, but even after reading the manual I can't find it. I've never dealt with EU electronics before, and am shamefully uninformed about electrical systems in general.

This transformer, seems like it could be a winner.

 

[FauxHall]

The nameplate above the cord looks like 100 watt. Double check

Get any 500 watt or higher rated step up transformer and you should be good.

The rule of thumb is rating 5x the demand. Make sure you get a "transformer" and not a "power converter." Transformers are heavy and solid. Power converters are solid state and hack the heck out of sine wave making lots of electronic hash.

 

[I LIKE MUSIC]

I found a sales sheet that lists the output power as 155 watts per channel at 4 Ohms, then goes on to say power consumption is 160 watts.

 

[FauxHall]

I see now. The 100w was for the switched outlets only. (I was looking via my cell phone earlier!)

Ignore the watts per channel as that is peak or something useless for power INPUT.

Use the 160w power consumption so 5 X 160w = 800 watt rating for the transformer. A 750w transformer would be close enough.

Here's my 500w transformer. I think I got it at a "hypermarket" for about the equivalent of $20.

 

[lattiboy]

Thanks all! Another place online told me it may be trivial to have it switched to 120V as there is mention of an internal switch in the service manual. I figure I'm going to deoxit anyway, so if it's obvious I'll give that a go when it's opened up.

If not, I'll grab a 1000W transformer off Amazon and report back.

 

[lini]

lb: Well, the switched outlets on your unit appear to be blocked, anyway, so these wouldn't have to be aditionally considered. Then I'd go by the main fuse (1209), which for 230 V use should be 3.15 A. Typically there are no 750 W units, but only 500 or 1000 W, so I'd get a 1000 W step-up unit - but before I'd of course check the possibility of internal rewiring. Problem is that the schematic of the PM7000/8000 is rather confusing in that regard, covering too many versions at once for me to properly get it...

Anyway, are you going to connect a turntable with regular MM or MI cartridge? Then you should mod the phono input and throw out the excessive input capacity in form of the two 470 pF caps (2253 & 2254) and the two 680 pF caps (2255 & 2256) and replace the latter two with a more sensible value like the 150 pF that are originally installed in the F and U variants. If you've got a cart that wants to "see" a very low load capacity, you could go even lower, but you'd better not go much below 100 pF, so the input doesn't receive Radio Moscow or whatever, if there's no turntable connected...

Oh, and there's a little bug in the block diagram, showing the "record selector" (the PM7000/8000/7200 aren't true record-selector designs) in position "off", but if you look at the position of the switches in the diagram, these are on position "source". And if you look at the implementation around the "record selector", it becomes clear that for whatever reason Marantz chose to ground the output to the delivering tape in both tape copy positions instead of leaving it connected to the selected source, so on these amps it's not possible to pipe a source signal through a processor on one tape loop and record the processed signal onto a recorder connected to the other tape loop via the tape copy functions of that pseudo "record selector". Just so you know, in case you'd ever want to try that.

Greetings from Munich!

Manfred / lini