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Odd Voltage Requirements (was: TU55 an ebay)

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MAC stuff that needs to go

silent700＠gmail.com

6 Oct 2010 6 Oct '10

12:57 a.m.

Here's an oddball, too: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220676550260 42V, 50hz. Apparently, there were mains lines that delivered those values to special plugs in Russian schools. How would one go about powering such a device in the US? -- jht

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cclist＠sydex.com

6 Oct 6 Oct

1:16 a.m.

On 6 Oct 2010 at 0:57, Jason T wrote:

Here's an oddball, too: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220676550260 42V, 50hz. Apparently, there were mains lines that delivered those values to special plugs in Russian schools. How would one go about powering such a device in the US?

I suspect that this will work on 60Hz, so at the easiest, a Variac would do the trick. You could also find a power transformer or two that would do the job nicely, say a 24V and an 18V combination. --Chuck

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ragooman＠gmail.com

9:14 a.m.

On Wed, Oct 6, 2010 at 12:57 AM, Jason T <silent700 at gmail.com> wrote:

Here's an oddball, too: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220676550260 42V, 50hz. Apparently, there were mains lines that delivered those values to special plugs in Russian schools. How would one go about powering such a device in the US?

just use a Bally transformer out of a the MPU-35 system pinball game, the 43V tap is used for the coils - which has plenty of power - there's piles of them here - that calculator is not even half the power as a pinball game =Dan --http://www.vintagecomputer.net/ragooman/

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ard＠p850ug1.demon.co.uk

2:44 p.m.

Here's an oddball, too: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220676550260 42V, 50hz. Apparently, there were mains lines that delivered those values to special plugs in Russian schools. How would one go about powering such a device in the US?

just use a Bally transformer out of a the MPU-35 system pinball game, the 43V tap is used for the coils - which has plenty of power - there's piles of them here - that calculator is not even half the power as a pinball game

Another posibility is to modify the devicec to work on whatever supply you have. What does itdo with that AC input? If it feeds it into a tranformer, what voltages come out of that? You may be able to replace the transformer with one that takes your mains input. I've done this several times to get US equipment running over here. -tony

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cisin＠xenosoft.com

5:11 p.m.

> > 42V, 50hz. Apparently, there were mains lines that delivered those > > values to special plugs in Russian schools. How would one go about > > powering such a device in the US?

On Wed, 6 Oct 2010, Tony Duell wrote:

Another posibility is to modify the devicec to work on whatever supply you have. What does itdo with that AC input? If it feeds it into a tranformer, what voltages come out of that? You may be able to replace the transformer with one that takes your mains input. I've done this several times to get US equipment running over here.

I suppose that is better than a motor turning a generator, or a power supply to convert 110V 60Hz to 12VDC, connected to an inverter that takes 12VDC, and outputs 42V 50Hz, which goes into the device's power supply that outputs 12VDC? :-) (although a few car batteries would smooth out the 12V, and provide a crude UPS) -- Grumpy Ol' Fred cisin at xenosoft.com

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ard＠p850ug1.demon.co.uk

7 Oct 7 Oct

4:04 p.m.

Another posibility is to modify the devicec to work on whatever supply you have. What does itdo with that AC input? If it feeds it into a tranformer, what voltages come out of that? You may be able to replace the transformer with one that takes your mains input. I've done this several times to get US equipment running over here.

I suppose that is better than a motor turning a generator, or a power supply to convert 110V 60Hz to 12VDC, connected to an inverter that takes 12VDC, and outputs 42V 50Hz, which goes into the device's power supply that outputs 12VDC? :-) (although a few car batteries would smooth out the 12V, and provide a crude UPS)

Hmmm... It depends on how 'original' you want the device to me. What I typically do is run it from astep-down transformer (provided it's not going to mind the lower mains frequency over here) to check that it works and to measure the transofrmer output voltages. And then I'll seriously consider replacing the transfoemr with one that has a 230V primary. If I care about originality, I leave the original transformer in place, and run it from the step-down transformer always. Of course if there's a mains voltage selector device I flip that. Therehas been one exception to all this so far. A 3rd-party power supply for the HP9114 HPIL disk drive (connects in place of the battery pack) that I believe was sold by a well-knwon HP calculator place. I was going to simply replace the transformer, but it was so badly made that IMHO it wasn't even safe for 115V mains input, let alone 230V. I simply built a complete new PSU -- properly! -tony

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ard＠p850ug1.demon.co.uk

6 Oct 6 Oct

2:39 p.m.

Here's an oddball, too: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220676550260 42V, 50hz. Apparently, there were mains lines that delivered those values to special plugs in Russian schools. How would one go about powering such a device in the US?

What is the device? In particular, is it going to care about the mains frequency. If it caould run at 42V 60Hz, you could use a simple step-down transofrmer to run it, I would recomend a double-wound (isolating) transformer, since an autotransformer, could end up putting the device 110V above ground, and I;d not trust the insulation to stand that. If it really does require 50Hzm then you basically either have to use a motor-generator set or rectify the US mains to get DC and re-chop it at 50Hz. You mightm for example, be abke to use one of the better (sine-wave output) Europena-market inverters to get 'mains' from a car battery (that would give you 230V, 50Hz) and a step-down transoformer. -tony

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pat＠computer-refuge.org

8:32 p.m.

On Wednesday, October 06, 2010, Tony Duell wrote:

Here's an oddball, too: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=220676550260 42V, 50hz. Apparently, there were mains lines that delivered those values to special plugs in Russian schools. How would one go about powering such a device in the US?

What is the device?

It's a 1990 or so (Russian) desktop calculator. Not like an HP "Calculator" computer, but a slightly more than 4-function calculator. Pat -- Purdue University Research Computing --- http://www.rcac.purdue.edu/ The Computer Refuge --- http://computer-refuge.org

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ard＠p850ug1.demon.co.uk
cclist＠sydex.com
cisin＠xenosoft.com
pat＠computer-refuge.org
ragooman＠gmail.com
silent700＠gmail.com