The Sinclair QL Forum

martyn_hill wrote:Hi Sparrowhawk

As regards power-supply - I am using a regular USB-type 'wall-wart' supply that can supply up to 1A, but I hacked the mini-USB end off and soldered-on the 2.1mm plug (+5V to the inner conductor) - which are pretty standard and easy to get a-hold of.

Hi Martyn, I'm afraid I never learnt to solder, so that option is not for me. However, Amazon had the following when I searched, would this or similar be suitable do you know?

https://www.amazon.co.uk/gp/aw/d/B071G22MST/

Thanks
Jean-Yves

Hi Jean-Yves

Yes, that looks right - positive polarity in the centre/inside (curiously referred to as the 'tip') of the 2.1mm (inner diameter) x 5.5mm (outer) barrel at 5V/1A.

Good luck.

tofro wrote:
This device is similar to the "dev" device and has the capability to disguise an arbitrary subdirectory as another device. Different from the dev device, it hides the subdirectory even a bit more...

Tobias

Thanks,

D.

martyn_hill wrote:Hi Jean-Yves

Yes, that looks right - positive polarity in the centre/inside (curiously referred to as the 'tip') of the 2.1mm (inner diameter) x 5.5mm (outer) barrel at 5V/1A.

Good luck.

Thank you!

Hi,

I could of supplied a Q68 power supply, but only a UK plug style.

So I took the decision not supply a power supply maybe this was a mistake, but I would have cater for EU, US, non-EU.

Derek_Stewart wrote:Hi,

I could of supplied a Q68 power supply, but only a UK plug style.

So I took the decision not supply a power supply maybe this was a mistake, but I would have cater for EU, US, non-EU.

A number of USB PSU/Chargers (the smart ones!) come with a detachable cable. Could you just supply such a cable with the Q68 plug at one end? (Apologies if this adds to your burden!)

Hi Per,

I made a USB A to 2.1mm barrel plug that connects to a 5v 1A iphone charger. This poweref the Q68 essily.

A similiar cable on eBay is £0.99, but a 5v 1A power supply is required. Which could cost £2

When a dedicated 5v 1a power supply uk mains plug costs £1.75

Also if a USB to power cable is used, there is a chance that someone will power the Q68 from PC USB port. Which work, but might over power the USB hub in the PC, if other USB devices are in use.

Sorry but I do not want take the chance of a Q68 powered from PC USB port, damsging the PC.

Derek_Stewart wrote:
Sorry but I do not want take the chance of a Q68 powered from PC USB port, damsging the PC.

It cant in any modern PC with Microsoft certification. The USB port is limited by hardware to 500mA.

(although old PCs there were about 20A or so available from USB port so equally cannot damage).

Derek_Stewart wrote: A similiar cable on eBay is £0.99, but a 5v 1A power supply is required. Which could cost £2

Surely, most people already have a couple of those PSUs by now

Also if a USB to power cable is used, there is a chance that someone will power the Q68 from PC USB port. Which work, but might over power the USB hub in the PC, if other USB devices are in use.

I guess the real risk is that "someone" wont read the effing manual, which would state in big red letters DONT DO IT! However I have an old laptop (2009, I think) and an external USB 2.5" harddrive with a dual USB plug for doubling the amps. The instructions (which I once read) said something like: If it doesnt work with one plug, use both. Ive never had to use both wherever Ive used it, though.

Sorry but I do not want take the chance of a Q68 powered from PC USB port, damsging the PC.

Im sure you have the experience - and the scars to prove it - to know what youre talking about! So Ill drop it there. Just my 0.002 bitcoin's worth. Ooops, 0.004 bitcoins by now!

I've made some photos of my Q68 - both cased and uncased - which can be viewed here.
(Don't worry - it's back in its case now and still working )

regards, Jan.