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Hi folks, I'm puzzling why the US CP/M R2.2 Multibank edition won't boot on my European QX10, but non-multibank 256K R2.2 works fine. Does it require a RAM board to work successfully, or DIP switch changes? Cheers,

Hi folks, I've got 7x VT420 logic boards here, untested for at least 20 years. VRT19 boards too. There's also a few PWS500au parts - CPU/heatsinks, LAN boards, PSUs, other misc items I've not gone through yet. The PWS parts were all bought as working originally. DECserver 90L, a tube of the 9V...

Hi folks, Turned my venerable HP1660A on today and the CRT is less than well. It's not quite vertically collapsing but the picture is wobbly and stretched at the top. Service manual flowchart says 'check voltages and signals -> check cable -> replace CRT module' :) I'm surprised that I...

Hi folks, I've finally got my hands on a QX-10 after 20 years of waiting patiently for one to land in my lap. It's a Euro ASCII edition with multifont card, 192k main RAM and 32k video RAM. I've managed to write some floppies using my Greaseweazle and drive B from the QX-10, all good. The...

Hi folks, I'm looking over an SWTPC S/09 6809 system for another museum, some of you may have seen me post about it on Twitter. It was working up until around a year ago then something went bang, we don't know what. Since then the PSU caps have also given up - both 8V and 16V rails collapse...

Hi folks, I'm temporary custodian of something I've never come across before in 20-odd years of collecting - a Sirius 1 made entirely of metal, even the keyboard case. When I first saw it I couldn't work out why it had flecks of rust on the top cover... ROMs appear to be v1.1 and the...

Hello folks, It's beginning to look like my venerable Pinmaster 48 has given up the ghost. After writing a couple of TMS2532JL-45s recently it started giving me 'mount error' on any EPROM I put in it for reading or writing. I thought it must be something like ageing caps failing so took the top...

Hi folks, I have a few boxes of 8" PL/M source disks written on an Intel MDS-series machine, type unknown. One of the disks has 'ISIS' on the label which means it's probably an FM encoded disk, not MMFM from ISIS-II. I've tried HFE, SCP and a raw flux dump from my Greaseweazle but none of the...

Hi folks, *edit* I've added the CRT board layout and the video service guide from the manual. I've obviously not been here for a week or two and we have a new look! I've not searched for a similar topic to this because I'm pretty sure nobody has asked for help on one of these before. The STC...

Hi folks, I've been running up and testing my oldest Apple ][+ to resurrect the first program I ever wrote in Apple Structured BASIC and getting ADTPro 2.10 going on it. Today I powered up and the display was rolling so I tweaked the horizontal hold on the monitor which fixed it for a bit then...

Hi folks, First off, happy new year. Cheers! Today's question is, I have 2 functioning Superbrains and to create disks for them I attach a Tandon TM100 from the SBII to my disk imaging PC and use ImageDisk to write new floppies. This works well. As a test last night I tried using the usual...

Hi folks, Since I can't, currently, make cpmtools read any of the Superbrain disk images I have I thought I'd try kermit for file transfers since I already have a distribution of 4.03 on one of the disks. Trouble is I don't know which port it was built for. The PC end is Win10 with an FTDI...

Hello folks, I've got this 1084 on the bench, sent to me because it went CRACK and the picture collapsed so there's obviously a fault in the vertical deflection circuit. Looking at the board the culprit was R346 which according to the schematic is a 4.7ohm resistor. Something prior to it is...

All I did was drive down to see forum member Zippysticks and they must've snuck into my car while we were chatting :D This means that, for now, I'm home to a dismantled SB1 QD and a pair of complete SBII QDs which are well known to JonB and StephenM. I've been after a Superbrain for 20 years...

Hi folks, An old DEC-related colleague of mine is trying to revive an RL02 drive with some packs and is starting with a thorough cleaning. BITD we had a company come round with a proper pack cleaner to service our disks but he's trying to totally dismantle the pack to get at both surfaces. I've...

Hi folks, Recently I dug out my B700 high profile, UK edition, and predictably it seemed dead. Probing with a 'scope showed activity though, and the CURSOR pin of the CRTC gave a trace of a flashing cursor so I checked over the video side of things. I could see a raster on the monitor plus H...

Hi folks, Long time no post, life and non-PET projects got in the way. I'm slimming down my PET collection because nobody needs 12 and I'm moving house, and was just going to list them on e*ay as faulty/untested. Then I realised my repairing conscience wouldn't let me do that* and have already...

Hi folks, I have a UK rarity in a Tandata PA 'personal organiser' and viewdata terminal, the keyboard PCB of which has been eaten by battery leakage - it's lost several copper pads and some of the interlink traces have disappeared too. Deeming it too expensive to repair/replace I'm looking at...

Hi folks, I have a pair of MBC555s which both work as expected (slowly :) ) until I add the apparently rare CGA+256K RAM card at which point they'll start booting then fail at the same point and just print "his hi hi" on screen. I'm using the official CGA boot floppy. If I disable the RAM on...

Hi folks, I think I'm looking in the abyss here given the amount of info around on these monitors, and it looks like I might be only 1 of 2 people in the UK with one, but I refuse to believe that Sanyo produced a CGA monitor JUST for the optional CGA graphics option on the MBC555. It was...