exxos's Atari, Amiga & retro forum

Hello, I was wondering if anyone had any ideas as to how I could fix the header on my TF1260 from only providing 9v as opposed to the 12v that is supposed to output?

My power supply (Meanwell RT-50B) is only a few years old and testing the 12v elsewhere is absolutely fine. So I really have no idea why I only get 9v. Any thoughts or suggestions would be very much appreciated.

Thanks

Gerry

I have tried the TF1260 in another A1200 and unfortunately I am still getting low voltage of the fan header. 8.93v according to my multimeter. Does anyone have any idea as to why this would be low and what I could do to correct it?

If you're worried about the speed of the fan. You can simply get a different wattage of fan.

Well it's not so much the fan speed I was thinking about, it's getting any fan to work. Only know of 5V 12V 18V 24V fans and I've tried a 12v and 5v which seem the most common with fans of that size and connecting to the header yields no activity at all. Having a deeper look online I do see 9v fans from China but I'm still puzzled by the fact I'm only seeing 8.93v. Seems a bit weird to me.

rabidgerry wrote: 22 Jan 2026 16:27 Well it's not so much the fan speed I was thinking about, it's getting any fan to work. Only know of 5V 12V 18V 24V fans and I've tried a 12v and 5v which seem the most common with fans of that size and connecting to the header yields no activity at all. Having a deeper look online I do see 9v fans from China but I'm still puzzled by the fact I'm only seeing 8.93v. Seems a bit weird to me.

I have a fan in my A1200 with Pistorm, it's a 12v low profile fan which I run off 5v to keep the noise down. Unfortunately I can't see the wattage as the label is upside down and partially obscured, but it does run.

It could be possible that the voltage is fine but there simply isn't enough amperage. Have you tried the fan from another connector such as the floppy drive power header? That's where I take 5v power for my 12v fan and it runs fine.

I also run a 12v fan on a 5v line.

rabidgerry wrote: 22 Jan 2026 16:27 Well it's not so much the fan speed I was thinking about, it's getting any fan to work. Only know of 5V 12V 18V 24V fans and I've tried a 12v and 5v which seem the most common with fans of that size and connecting to the header yields no activity at all. Having a deeper look online I do see 9v fans from China but I'm still puzzled by the fact I'm only seeing 8.93v. Seems a bit weird to me.

It *could* be that it only reads as 12V when under load. Usually 12V is unregulated and fluctuates depending on load applied. You don't need to worry about matching voltage exactly, if it's at 9V on the header then a 12V fan should just run slightly slower. If it doesn't run at all, then perhaps the wattage of the fan is too high, try a lower watt 12v fan.

I tried 3 different fans for the sake of experimentation. None of them work at all. But they all run off the floppy header. I find this really bizarre indeed. Now I could run them from there permanently but it's a much neater solution obviously if I can run it from the TF1260 card.

Lower wattage fan? Any fans I ever see to purchase for this type of allocation never even mentions watts. I'll have a nosey and see what is out their.

@Steve, fancy measuring the header volts output on your TF1260 if you get a bit of time? Just curious as to what yours reads. That is if you have a multi-meter of course.

@rabidgerry I would try and verify that the solder joints and tracks for the fan connector are all good. It could be that you have a good +ve but a bad ground on the fan connector. Also measure the voltage where it feeds into the TF1260.

rabidgerry wrote: 23 Jan 2026 16:55 I tried 3 different fans for the sake of experimentation. None of them work at all. But they all run off the floppy header. I find this really bizarre indeed.

Is that at 5v or 12v?

As @PhilC suggested, you may have a bad connection at the fan header or where the 12v comes into the TF1260 , but it certainly seems that there isn't enough power especially if the fans work from another power point on the same machine.