Don't forget to check your power supply

[Brian B]

I recently acquired on Ebay a Renaissance Sparc and just received it yesterday. Everything was well packed and complete, as I expected it would be. As a matter of course, I always check the output of any unknown or new to me power supply. It is quick and could save a lot of headaches.

This particular power supply was marked "Saitek Sparc", so no worries in getting it mixed up, plus it was an original with the exact requirements marked on it. I have to use a voltage transformer to kick it up from 120V to 240V to use the European plug here in the USA. I plugged it in and checked it with my DMM, 14.94V, not the 10V as expected. I am sure it was the transformer that was pushing it too high. This test was unloaded, but even with a load it wouldn't have been anywhere near 10V. I decided to use a 9V adapter and it works fine. I checked the 9V adapter, too as it was new, 9.1V.

Just goes to show you that power supplies can perform differently depending on the input and transformer, so be sure to check these out. Even if the computer is from a knowledgeable and trusted collector, it is worth taking the time to be sure how the adapter will perform at your house.

Close one regards,
Brian B

[Larry]

There is a voltage regulator inside the computer to drop the voltage down to the CPU's correct
voltage. Regulators need a load if they are to work properly.
Check the output voltage on a Fidelity adaptor, it will also read about 14 volts when not under load.
L

[chesspcmac]

Hi Larry, you seem to Know a lot about the adapters. one question?
I bought a Montreux with an regulated adapter, it works well with a 6V 1amp adapter. I think the right adapter for the montreux is 5.6 v 1A. While checking my boxes I found and adapter that is regulated 5.6v but 2.68 A, which of these two is better:
1) Regulated adapter 6v 1A or
2) Regulated adapter 5.6 2.68?

I know amperage is less harmful than Voltage but ...which is better - less harmful- in this case??
any advice is welcomed

Electric regards

Mike

[Larry]

Hi Larry, you seem to Know a lot about the adapters. one question?
I bought a Montreux with an regulated adapter, it works well with a 6V 1amp adapter. I think the right adapter for the montreux is 5.6 v 1A. While checking my boxes I found and adapter that is regulated 5.6v but 2.68 A, which of these two is better:
1) Regulated adapter 6v 1A or
2) Regulated adapter 5.6 2.68?

I know amperage is less harmful than Voltage but ...which is better - less harmful- in this case??
any advice is welcomed

Electric regards

Mike

Hi Mike, you are fine with either adaptor. Just remember to treat
an unregulated adaptor as you would treat a black snake.
L

[Brian B]

There is a voltage regulator inside the computer to drop the voltage down to the CPU's correct
voltage. Regulators need a load if they are to work properly.
Check the output voltage on a Fidelity adaptor, it will also read about 14 volts when not under load.
L

That adapter might be fine, I am not taking a chance on it. I have tested all of the other adapters on my other computers in the past year and none of them were running 5V higher than spec unloaded so that is why I didn't hook it up. My other Renaissance adapter reads 11.94V unloaded and it supplies 9V when loaded. Part of the issue may be that my step-up transformer is 240V and the Saitek Sparc adapter is 220V, so I would expect it would measure slightly higher. Who knows? Not worth it to me to take the chance.

I will admit anything I know about electricity is self taught, and sometimes the hard way, ha! That said, I have rebuilt dozens of power supplies for pinball machines and seen my share of components damaged by over current, so too much juice can cause problems.

Just a note to be careful out there.

Safety regards,
Brian B