TF1260 Fan header voltage problem

Help & news on accelerators from TF, Amiga, Atari, CD32 etc

Moderators: terriblefire, Terriblefire Moderator

User avatar
rabidgerry
Posts: 20
Joined: 02 Feb 2022 12:48

TF1260 Fan header voltage problem

Post by rabidgerry »

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
User avatar
rabidgerry
Posts: 20
Joined: 02 Feb 2022 12:48

Re: TF1260 Fan header voltage problem

Post by rabidgerry »

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?
Steve
Posts: 3305
Joined: 15 Sep 2017 11:49

Re: TF1260 Fan header voltage problem

Post by Steve »

If you're worried about the speed of the fan. You can simply get a different wattage of fan.
User avatar
rabidgerry
Posts: 20
Joined: 02 Feb 2022 12:48

Re: TF1260 Fan header voltage problem

Post by rabidgerry »

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.
User avatar
rubber_jonnie
Site Admin
Site Admin
Posts: 14888
Joined: 17 Aug 2017 19:40
Location: Essex

Re: TF1260 Fan header voltage problem

Post by rubber_jonnie »

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.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...
matt020
Posts: 326
Joined: 29 Sep 2019 09:17
Location: West Australia

Re: TF1260 Fan header voltage problem

Post by matt020 »

I also run a 12v fan on a 5v line.
Steve
Posts: 3305
Joined: 15 Sep 2017 11:49

Re: TF1260 Fan header voltage problem

Post by Steve »

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.
User avatar
rabidgerry
Posts: 20
Joined: 02 Feb 2022 12:48

Re: TF1260 Fan header voltage problem

Post by rabidgerry »

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.
User avatar
PhilC
Moderator
Moderator
Posts: 7441
Joined: 23 Mar 2018 20:22

Re: TF1260 Fan header voltage problem

Post by PhilC »

@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.
If it ain't broke, test it to Destruction.
User avatar
rubber_jonnie
Site Admin
Site Admin
Posts: 14888
Joined: 17 Aug 2017 19:40
Location: Essex

Re: TF1260 Fan header voltage problem

Post by rubber_jonnie »

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.
Collector of many retro things!
800XL and 65XE both with Ultimate1MB,VBXL/XE & PokeyMax, SIDE3, SDrive Max, 2x 1010 cassette, 2x 1050 one with Happy mod, 3x 2600 Jr, 7800 and Lynx II
Approx 20 STs, including a 520 STM, 520 STFMs, 3x Mega ST, MSTE & 2x 32 Mhz boosted STEs
Plus the rest, totalling around 50 machines including a QL, 3x BBC Model B, Electron, Spectrums, ZX81 etc...

Return to “Terriblefire's channel”

Who is online

Users browsing this forum: ClaudeBot, semrush [bot] and 4 guests