Mac Plus Novy and Gemini Ultra Extra Power

[Kevinlenane]

Hi I have a couple of 030 Mac Plus accelerators and both hAve a way to grab extra power via red and black clips that I recall clip on to a resistor on the power sweep board. Does anyone know which resistor you can do this with? I just can't find a manual around this task.

 

[Phipli]

Nice cards you might want to consider a fan too.

This guy on YouTube might be able to help if you comment under his video. I know it is a 512k, and not the same card, but there is a lot of commonality, or he might have the manual.

 

[Kevinlenane]

I have one w a fan too. Im missing the powercord for it - but it also has to clip
In...

 

[Phipli]

I have the Gemini Ultra, but mine is set up for an SE, so doesn't have the leads or processor clip. Plus I don't have the manual sadly.

 

[Phipli]

Hi I have a couple of 030 Mac Plus accelerators and both hAve a way to grab extra power via red and black clips that I recall clip on to a resistor on the power sweep board. Does anyone know which resistor you can do this with? I just can't find a manual around this task.

I've realised the comments under the video already include a discussion on where the clips go, seems they've likely answered your question?

 

[Kevinlenane]

Ah it appears cr24 and cr25 are options.

 

[Kevinlenane]

Full disclosure - i tinkered w running power from CRx and started a moderate electrical fire inside my Plus. I have a different problem now I'm in timeout until I can find a manual.

 

[Phipli]

Full disclosure - i tinkered w running power from CRx and started a moderate electrical fire inside my Plus. I have a different problem now I'm in timeout until I can find a manual.

:/

Ah, that's not good. Are the cards OK? A Plus is at least fairly easy to repair, but the cards are... Tricky.

Perhaps test the voltages with the multimeter first before the next try.

 

[Kevinlenane]

:/

Ah, that's not good. Are the cards OK? A Plus is at least fairly easy to repair, but the cards are... Tricky.

Perhaps test the voltages with the multimeter first before the next try.

Yes fortunately the card is okay - the Plus really gave me a light show though.

 

[desertrout]

Full disclosure - i tinkered w running power from CRx and started a moderate electrical fire inside my Plus. I have a different problem now I'm in timeout until I can find a manual.

Whoa - sounds like you were connecting straight to mains voltages. The board is only supposed to receive +5V and GND, so hopefully everything is ok... sounds like it is. In this case, I believe you should be tapping +5V and GND from the logic board, which should be easy.

I have one w a fan too. Im missing the powercord for it - but it also has to clip
In...

I have a couple of these Novy boards, and it's nice yours already comes with the additional PSU - which should connect directly to mains. It's an option to do something similar with the Gemini (the guy in the video mentions his has one)... get a Meanwell PD-25A and use that to power it instead of trying to pull from the analog or logic boards. And you'll have +12V for the fan you may want to add. Takes stress off the AB

 

[Kevinlenane]

Whoa - sounds like you were connecting straight to mains voltages. The board is only supposed to receive +5V and GND, so hopefully everything is ok... sounds like it is. In this case, I believe you should be tapping +5V and GND from the logic board, which should be easy.


I have a couple of these Novy boards, and it's nice yours already comes with the additional PSU - which should connect directly to mains. It's an option to do something similar with the Gemini (the guy in the video mentions his has one)... get a Meanwell PD-25A and use that to power it instead of trying to pull from the analog or logic boards. And you'll have +12V for the fan you may want to add. Takes stress off the AB

Thanks for the tip! Btw - what's the cable called that runs off the Meanwell? It's the same 4-pin connector on my fan pictured above w one of the pins set off to one side...

 

[cheesestraws]

Full disclosure - i tinkered w running power from CRx and started a moderate electrical fire inside my Plus. I have a different problem now I'm in timeout until I can find a manual.

Ah it appears cr24 and cr25 are options.

CR24 and CR25 on the AB are part of the bridge rectifier in the power supply, assuming you've got a 120V AB. This means that, yes:

Whoa - sounds like you were connecting straight to mains voltages

yes, you were basically getting full mains voltage off it. No wonder it made a bang. That must have been scary.

@Kevinlenane, do you have the AB schematic/explanation document? If not, would you like it?

 

[Phipli]

CR24 and CR25 on the AB are part of the bridge rectifier in the power supply, assuming you've got a 120V AB. This means that, yes:



yes, you were basically getting full mains voltage off it. No wonder it made a bang. That must have been scary.

@Kevinlenane, do you have the AB schematic/explanation document? If not, would you like it?

Yikes. Sounds like the other users are connecting a PSU in, not the board. Do you have the auxiliary PSU?

 

[desertrout]

Thanks for the tip! Btw - what's the cable called that runs off the Meanwell? It's the same 4-pin connector on my fan pictured above w one of the pins set off to one side...

For the +5V/+12V output? I don't know if it has a name, but any 4-position assembly with this connector should work: https://www.digikey.com/en/products/detail/molex/0022013047/26435

Edit: here's the datasheet for the Meanwell: https://www.meanwellusa.com/upload/pdf/PD-25/PD-25-spec.pdf

 

[Kevinlenane]

For the +5V/+12V output? I don't know if it has a name, but any 4-position assembly with this connector should work: https://www.digikey.com/en/products/detail/molex/0022013047/26435

Edit: here's the datasheet for the Meanwell: https://www.meanwellusa.com/upload/pdf/PD-25/PD-25-spec.pdf

Well one pin is farther off the side - it's ab the width of molex with on offset pin

 

[desertrout]

Well one pin is farther off the side - it's ab the width of molex with on offset pin

Oooooh - I see, I think that's the mains input connector for your PSU... it looks to me like that connector only uses pins one and three but I can't see the whole thing. I can't imagine what that offset pin is for - is it connected to anything?

 

[Kevinlenane]

Oooooh - I see, I think that's the mains input connector for your PSU... it looks to me like that connector only uses pins one and three but I can't see the whole thing. I can't imagine what that offset pin is for - is it connected to anything?

Well this one is where the 030 board gets plugged in - the board into this fan unit - then this gets plugged in presumably from the vacant connector w the one pin a bit wider than the rest. Do you see the connector now here (not the one w a cord plugged in)? It's the same kind as the psu we've been referencing and I'll need a couple of these cords to power the boards apparently.

 

[Kevinlenane]

This one goes w the Novy btw not the Gemini which will require the PSU w the same connector.

 

[desertrout]

Yeah I saw the offset pin, but what I can't see is what it's connected to. From one of the other images, all I see is pins 1 and 3 having traces, which make sense given this is mains input (there's only going to be GND and 120V)... but I could be wrong about the other two.

The Meanwell has a different header for mains input - a three-position molex, but only positions 1 and 3 are populated. There's no offset. The 4-pin header on the Meanwell is the +5V and +12V output with grounds on pins 2 and 3. Your Novy PSU and the Meanwell are very different.

It might help if you have a model number of the Novy's PSU, or some images of the top and bottom.