The Sinclair QL Forum

Interesting development, Fred :-) As for the placement of the two original ROMs, actually it doesn't matter at all which of the two sockets they are fitted in to as both have exactly the same pinout. The Masked ROMs take this in their stride due to the way the Chip select logic is enabled in each RO...

Halo Fred! From what you describe, either something was 'disturbed' when removing/replacing/switching back the two ROMs, the legs weren't seated correctly in their sockets or, (hopefully not), the 8301 ULA has died coincidentally with your upgrade attempt. Unlikely to be a DRAM failure, though the B...

Hello everyone! I just wanted to share an initial, personal review of this weekend's meeting in Dormagen: Well, what a terrific event! Detlef is to be commended for his excellent organisation and generosity in bringing us together! For many years I have exchanged emails and posts via the various for...

Hi again Robbizz!

OK, so all I personally can think-of is that this monitor doesn't like the QL's 'over-scan' timing and is struggling to sync properly.

(BTW, as you observed, I misnamed the SCART Video-In pin - yes,its pin-20, not 18.)

Keep us posted

Good morning all - and Happy Mother's Day to our mainland European friends :-) Just to close the loop on this request - after many hours of unpacking, searching for, reviewing and then scanning-in the Thor Technical Manual, Urs Koenig has very generously made available the FULL technical manaul that...

Hi Robbizz! [Edited to correct SCART pin numbering in original post] I've had success creating a number of QL -> SCART cables over time, based more or less on the really useful site: http://www.fruitcake.plus.com/Sinclair/Spectrum128/SCARTCable/Spectrum128SCARTCableQL.htm I guess you might have used...

Hi Martin For what its worth, attached here is an image from an old capture-trace I took of the MDV signal lines at the very start of a 'DIR mdv3_', as seen at the MDV-Extension port. MDV3 was a ZX unit, attached externally to the QL, as you'd imagine. MDV3_trace.png A few points: a) I was wrong abo...

Hi again Martin Not sure how a multimeter would.ipact your readings, but I regularly use my simple/cheapo USB digital analyser with PulseView software to monitor those signals. Monitoring the Erase and WP lines requires a bit of circuitry to prepare the signals for capture, but the 'sort of digital'...

Hi Martin! No harm in replacing the Cap in the reset cct, I'm sure. If the problem goes away after a further reset, it could be the 15MHz oscillator driving the ZX8302 ageing and not stabilising 'quickly enough.' But that's just speculation. As for the method used to select each MDV unit, I think I ...

Hi Martin! I've never had a problem with RESET that required that Cap to be replaced - when I have hitn problems with reset, it was either down to the ZX8302 or something more fundamental with the main ZX8301, but replacing the Cap is a simple and cheap enough operation to eliminate it. I am in the ...