UK Sinclair QL Microdrives not working in the USA

[AustinDan]

hi,
I recently purchased 2 fully working QL's in the UK and now have them proudly showcased in my humble computer museum in Texas, US. That's the good news. The bad news is this:

One of the QL's does the normal Drive 1 test at startup looking for a tape etc. However, it (and drive 2) both fail to load known working tape media. The drives simply spin continuously without loading data.

The mystery then gets even weirder: the 2nd QL boots just fine but refuses to even recognize or acknowledge that drives 1 and 2 even exist. Same thing if i connect an external micro drive as drive 3 (i know the drive is fine as i use it with my Spectrum with no issues). AM wondering if there is some type of issue with the drive controller (if there is such a thing?).

Anyone got any suggestions as to what is going on and how to fix it? I have tried both machines using a Native QL 110V US power supply as well as a UK 240V QL power supply running through a 110V to 240V converter.

This may sound odd but could it be connected with the fact that the US runs at 60HZ instead of the UK 50HZ power?

Big case of beer for anyone that can help me with these 2 machines!
Dan

[Wimdev]

I have a UK QL as well (as well as 3 US-spec QLs). I found that re-seating the microdrive connectors on the PCB helped. None of my microdrives were very reliable and neither of 2 UK-spec microdrives initially worked. Swapping them amongst my other QLs seemed to have fixed things (mdv1's for mdv1's etc), though I'm not sure if I eventually wound up with the original drives in my UK QL.

By the way, as far as I know, mdv2 won't work unless mdv1 is working. Swapping the 220 / 110 V power supplies didn't make any difference. Currently, I run the UK QL off a US 110V power supply, and a US QL through an inverter using the UK power supply.

Finally, you might want to clean the heads with rubbing alcohol. Also try formatting a microdrive over trying to read it. A format fails much quicker if there's anything wrong - doing a dir can take minutes to fail.

Good luck,
Wim

[RWAP]

Just thought I should own up - the machine which now refuses to even try accessing mdv1 or mdv2, was supplied by me and was working fine when Dan first received it.

The one which refuses to read cartridges, was recently repaired by me - Dan asked me to look at the microdrive units which were displaying this erratic behaviour - I cleaned mdv2, and, although mdv1_ would read once it had been cleaned, it would not format / write to cartridge, so I changed the unit. I changed both drive rollers and they were both working fine before I sent the machine back to Dan.

I know I am a common factor, but don't think it's me....

The other common factor is of course, Dan's power supply in the house - wonder if it is noisy - ideally he could do with checking them at another house / using other power supplies - Dave is not that far away (ie they are both in texas!)

[Spirantho]

Hi everybody,

Rich pointed me to this thread - this is what I replied to him earlier:

Sounds like his ZX8302 is dead or (quite possibly) came loose in transit on the one that doesn't see his microdrives at all.
The other one sounds like the problem I've been having. My home QL had mdv2_ that would read and sometimes write, but wouldn't format. I cleaned the heads - no change. I re-surfaced the rubber roller (pencil erasers are wonderful things) to get rid of the smooth layer on top to make it grip better. It still didn't format... but then it did!
Same with my work QL - mdv1_ steadfastly refused to format, but read and (sometimes) wrote. So did my changes, cleaned the head several times... kept trying...
.. and eventually it worked! Now it formats the same cartridge repeatedly, just fine, whereas before it would say "format failed" because (presumably) not enough blocks were successfully written.

Everything seems nice on both QLs, now - I just needed to keep formatting over and over again. I think it's to do with the motor being a little irregular when it's not been used for a long time. Reading wouldn't be a problem because there's enough tolerance in the read routine - but if you're writing to a cartridge the error can be twice - imagine the motor is fast on one bit of tape when writing, and slow on the same bit when reading: you'd get twice the normal timing error.

Either way, the best thing to do, it seems so far, is to just keep trying to format it, cleaning the head several times as you do it. Of course his problem may be something entirely different.

[Dave]

Dan,

I'm just north of Round Rock. Want me to take a look? I have a LOT of spare Samsung mechanisms here and should be able to get you working. I also have a couple of spare US PSUs.... Which reminds me.... I need to mail one out to someone!

Dave

[Dave]

Ok, I have connected with Dan by phone. He is coming over on Tuesday and we'll get to the bottom of this. Luckily, Rich sent me some spare parts a while back, so if it needs an 8302 or etc. I can get him going at no cost.

[RWAP]

From past experience, be prepared for it to be a problem with the electricity in Dan's house

Ie. check you can replicate it before trying to fix it!

[Dave]

It's very unlikely a power issue, given the good quality of the local power distribution network. That said, they are British QLs and are very prone to making and receiving RF noise.

They have probably been knocked about a lot on the flight over. I'll just look them over, then reseat everything and try again. Failing that, I'll whip out the oscilloscope and see what's actually happening - it's good to know if it's a read or a write problem or something else.

We'll figure it out.

[vanpeebles]

Did you get it working in the end?

[Dave]

We had to reschedule to Saturday. I'm working in Dallas this week.