Thanks for the great update!
The Chroma for the PAL signal for the modulator is governed by the far left hand side of the board. I think from memory there's a preset (dial) which you may be able to twiddle to get colour? Should be close to a 4.43MHz crystal.
If it helps any, look at http://mutantcaterpillar.Wordpress.com as I put a Sam repair on not long ago.
Ian - I officially love you and want to have your babies!!!!!!! Twiddling the little dial just next to the crystal has indeed brought glorious technicolour back to my Sam Coupe!
Thanks a bunch for that advice. This website is singularly the best website on the internet by a long chalk for all the amazing wealth of information that it's users pass on to other people.
I now have a 99% working Sam Coupe which is only missing a working ESC key.
You may or may not know that F9 is a hard coded short-cut for BOOT. IT is a small thing but I find it incredibly convenient. I've used it way more than the ESC key :)
Cheers for that bit of info spud. I guess I'm still well and truly cutting my teeth on the Sam and didn't know that. If you had to choose one of the F-keys to sacrifice for an ESC key which one would be the one that gets used the least?
Fantastic work on repairing the drive. Well done :)
Thanks! It was a real adventure and to be honest I wasn't overly confident that it would work after seeing what looked like 100 different pieces of floppy drive laid out on the kitchen table! I got it wrong a couple of times when reassembling it, couldn't remember exactly how the upper head assembly went back in there (that's why I wished I'd taken photos beforehand) and kept getting "19 Loading Error 0:1" message from Sam, obviously because the upper head wasn't connecting with the disc correctly. Once I finally figured it out and reassembled it correct I was rather elated to say the least when Comet finally booted! I could strip and reassemble one now in no time at all!
Welcome to the club. [plug] Be sure to download a copy of Dave Invaders from Black Jet to treat your SAM to a brand new game :) [/plug]
I've already played your excellent Dave Invaders in Sim Coupe so now I'm going to give it a bash on the real deal, it'll be even better now that colour has been restored!
I'm looking forward to doing some development work on the Sam myself, looks like quite a capable machine to develop for.
Well done getting the disk drive back up and working - I couldn't justify the hours to take it apart and re-assemble. I have some spare +3 drive belts if you need a replacement.
Colour used to work on my TV, but I was struggling to get either colour or a stable picture.
I did replace the TV lead from the PSU (as the original was extremely short!) so that may be worth looking at - although it only pushes into a socket on the PSU.
Presumably this should be fine with a SCART cable, unless something has happened in transit.
Thanks Rich! I need a couple of spare +3 belts, I'll drop you a PM for them.
As you've probably read above, colour has now been restored thanks to some excellent advice from Ian. I'll still be choosing to use the scart cable once it arrives but in the meantime at least I can enjoy up to 128 colours on screen all at once! I feel so spoiled after only having 16 colours on screen with the Spectrum!
Thanks once again for making all this possible for me by selling me the Sam in the first place, we wouldn't be here now if it weren't for you. You're a true credit to this fine community.
OK, so the ?6.50 Roctec external drive arrived from the eBay seller this morning. I was happy to find out that it was an RF332C model. I stripped the drive mechanism from the casing and it's a Citizen UODC-12A mech. I put it side by side with the Citizen UODC-09A mech that's in my SamDrive and the two look almost identical. There's a couple of minor differences to the chassis design but the major components such as the drive heads/stepper motor assembly/drive motor are all identical. I'm sure it would be possible to use all the mechanics from one drive in the other.
Unfortunately it's impossible for me to test this drive as MGT solder their proprietary drive controller interface directly to the 26-way header at the back of the drive board where as the Roctec drive merely has a 26-way ribbon cable connecting the header to the drive controller board that sits in the external housing. It would mean desoldering the Sam controller interface and soldering it to the Roctec drive, something which I'm not prepared to do with the knowledge that I already have a fully working drive which I don't want to risk.
At a pinch I could get some female to female jumper leads and wire the Roctec in parallel with the SamDrive so that control signals sent from the drive interface would go to both drives at the same time. However I'm not sure how the Sam would react to this and don't want to damage the drive controller so I'm going to can that idea!
I don't have an Amiga so, even though I suspect it's only a worn drive belt in the Roctec which is the reason for the seller to sell it as 'non-working', it will just have to get filed away in the loft in case my working SamDrive ever stops working. Either that I find another WOSser in the Leeds area with an Amiga and take it to their house to test! I guess it's a bit extreme to buy a cheap Amiga off the bay just to test a potentially dead external drive!
In the meantime I've managed to get in contact with the legendary Edwin Blink of Atom Lite/Comet assembler/B-DOS fame and am about to order an Atom Lite from him. My Sam is really starting to come alive now!
Comments
Ian - I officially love you and want to have your babies!!!!!!! Twiddling the little dial just next to the crystal has indeed brought glorious technicolour back to my Sam Coupe!
Thanks a bunch for that advice. This website is singularly the best website on the internet by a long chalk for all the amazing wealth of information that it's users pass on to other people.
I now have a 99% working Sam Coupe which is only missing a working ESC key.
Cheers
Thanks! It was a real adventure and to be honest I wasn't overly confident that it would work after seeing what looked like 100 different pieces of floppy drive laid out on the kitchen table! I got it wrong a couple of times when reassembling it, couldn't remember exactly how the upper head assembly went back in there (that's why I wished I'd taken photos beforehand) and kept getting "19 Loading Error 0:1" message from Sam, obviously because the upper head wasn't connecting with the disc correctly. Once I finally figured it out and reassembled it correct I was rather elated to say the least when Comet finally booted! I could strip and reassemble one now in no time at all!
I've already played your excellent Dave Invaders in Sim Coupe so now I'm going to give it a bash on the real deal, it'll be even better now that colour has been restored!
I'm looking forward to doing some development work on the Sam myself, looks like quite a capable machine to develop for.
Thanks Rich! I need a couple of spare +3 belts, I'll drop you a PM for them.
As you've probably read above, colour has now been restored thanks to some excellent advice from Ian. I'll still be choosing to use the scart cable once it arrives but in the meantime at least I can enjoy up to 128 colours on screen all at once! I feel so spoiled after only having 16 colours on screen with the Spectrum!
Thanks once again for making all this possible for me by selling me the Sam in the first place, we wouldn't be here now if it weren't for you. You're a true credit to this fine community.
OK, just don't tell the wife, hey? :)
Seriously, glad I could help!
Unfortunately it's impossible for me to test this drive as MGT solder their proprietary drive controller interface directly to the 26-way header at the back of the drive board where as the Roctec drive merely has a 26-way ribbon cable connecting the header to the drive controller board that sits in the external housing. It would mean desoldering the Sam controller interface and soldering it to the Roctec drive, something which I'm not prepared to do with the knowledge that I already have a fully working drive which I don't want to risk.
At a pinch I could get some female to female jumper leads and wire the Roctec in parallel with the SamDrive so that control signals sent from the drive interface would go to both drives at the same time. However I'm not sure how the Sam would react to this and don't want to damage the drive controller so I'm going to can that idea!
I don't have an Amiga so, even though I suspect it's only a worn drive belt in the Roctec which is the reason for the seller to sell it as 'non-working', it will just have to get filed away in the loft in case my working SamDrive ever stops working. Either that I find another WOSser in the Leeds area with an Amiga and take it to their house to test! I guess it's a bit extreme to buy a cheap Amiga off the bay just to test a potentially dead external drive!
In the meantime I've managed to get in contact with the legendary Edwin Blink of Atom Lite/Comet assembler/B-DOS fame and am about to order an Atom Lite from him. My Sam is really starting to come alive now!