120V-220V converter - Macintosh 128/512/Plus

[BadGoldEagle]

Hey guys/gals

Just bought a non working 512K Hyperdrive. It comes from the US and therefore it needs 110V, not more, not less, in order to work properly.

I live in France, and we use 220-230V around here. Buying a step-down transformer isn't a big deal. But I worry about frequencies.

In the US you guys use 60Hz and in Europe, we use 50Hz.

According to the label, it doesn't matter if it's 50 or 60Hz, as long as the voltage is 110V. Should I trust this or try to get a fancier model/setup to convert the Hz as well as the voltage? I know that the frequency is kinda important with really old turntables/radio/reel-to-reels. But what about Macs?



Thanks!

PS: Of course I know that since it's a non working machine it won't work straight out of the box. But I need to power it on to diagnose what's wrong !

 

[apm]

I'm in the UK, and I've used a simple 220V-110V step-down transformer with an American Plus with no problems. When I bought a 128k a couple weeks ago (also a US model), the person I bought it from was using an identical transformer. So it appears that 50/60Hz doesn't matter.

 

[rsolberg]

APM, would you mind posting a photo of one of your transformers? Just curiosity from across the pond here. I'm only familiar with the travel style stepdown units which tend to be limited to 50 watts output, or the "hairdryer" 1600 watt "converters" that only work with resistive loads like heating elements.

 

[bibilit]

Hi Lambert,

Finding an "International" Analog Board will probably be the best solution in the long run, or part exchanging it with the 110 V one.

To test it, you can use your Plus, Logic board can be swapped easily.

The hyperdrive is present ?

 

[BadGoldEagle]

Yeah the Hyperdrive is in there.  But I think this is a 1985 model (will know when it'll arrive), and the Hyperdrive PSU is 110Volts only. In 1986 they changed a few things, adding a switching power supply.

So apparently it doesn't matter if my step-down transformer outputs 110V @50Hz.

Techmoan had to use a very complicated setup to use his wire recorder, because a lower frequency meant the recording was playing slower as it should.

 

[BadGoldEagle]

I had a look at my options. There are a couple of step-down transformers on amazon. Most of the ratings say this is a good product but some people had their machine/appliance destroyed... I don't know what to think.

Would a surge protector help if the transformer fails ?

 

[techknight]

Or, move to the US so you can just plug it right in. lol. 

We have 220/240V here as well, but its split phase. for some reason everything is 110 to 125 off of one of the phases. 

 

[apm]

Both my transformers look like this, though with different brand names printed on the front:

http://www.maplin.co.uk/p/240v-to-110v-300w-voltage-converter-vr05f

50Hz vs. 60Hz is not a big deal for the switching power supplies in the Mac. The first thing the power supply does is rectify the line voltage to DC, then the rest of the power supply operates via high-frequency switching. So unlike AC motors where the rotation speed is coupled to the line frequency, here it typically doesn't matter.

 

[BadGoldEagle]

Thanks APM for all that info. Even though I plan on moving to the UK later (if you guys let me in of course...), I live in France for now. 

I think I'll settle for this transformer. Yeah I know it's all in French as I couldn't find any information elsewhere. 

What I'm really worried about is the transformer ruining my Mac. So do you think a surge protector would help? 

 

[BadGoldEagle]

Small update: I found another transformer on ebay. It's exactly the same as yours but with the Euro plug, 300 Watts. 60€ shipped. Bought.

 

[rsolberg]

Nice find BadGoldEagle. Thanks for posting the link APM. It's fairly trivial to use 220-240v European devices here in North America as long as they'll tolerate 60Hz. Our split bus residential wiring system has two hots with 230v between them, plus a centre tapped neutral with 115v from either hot. Our general purpose receptacles and lighting use the 115v, but large appliances such as electric stoves, ovens, clothes dryers, built in heaters, and welders use 230v.

 

[apm]

Sorry for the slow turnaround BadGoldEagle. Probably the other one would have been fine too, though I was a little unclear about how it achieved the conversion in both directions (apparently automatically?). Anyway, the type i've used and that you've now found is really simple, just a bit iron and copper transformer that does the job.

 

[BadGoldEagle]

No problem mate. Thank you for suggesting this product in the first place. I think some of these things are actually scams in disguise, made in China of all places. 

Since you didn't run into major problems with yours, I guess I won't with this one. The brand's different, but I bet you can't tell the difference between the two from the inside.

Maybe I won't need it much though. Some later models of the Mac Hyperdrive had a switching power supply while the early models didn't. The switch happened sometime in late 85 or early 86, I don't know for sure. I hope the one I bought has the later type of PSU. I could swap the Mac's AB and set a few jumpers differently. That would be really easy. Only time will tell...