27-04-2020, 01:49 PM
This reminds me of my KV-1820, which is pretty much the only survivor of my "TV cull" a few years back (all were given away rather than dumped, so hopefully live on. I still regret giving away my Philips set with a Teletext printer). Anyway, I think I must have been very lucky, as I've never had a failed CGS, but unlike the notorious 1810, there's only one in the line output stage, and it seems to be very reliable in the 1820.
Over the years, I saw many 1820s, and all had tired CRTs, but the one I've kept is unusual as it's like new - pin sharp and bright. Good greyscale too - normally the tracking between guns goes bad as the tube ages, meaning compromises are required when setting up. I've seen lots of faults, but usually capacitors - the big blue film caps on the timebase board, normally. One thing that did help me fairly early on - there was a later PSU with over-current protection, so timebase faults in the set wouldn't then immediately take out the PSU. I don't care about originality - that PSU has been in my set for as long as I can remember, and has been invaluable!
I haven't powered it for 20 years or more, but I'm sure it'll work with minimal effort. It's been stored inside all that time I've owned it. I do have another, that was given to me about 7 years ago, and that has works well (apart from the usual soft CRT). It has a marginally better cabinet, so you can guess what's going to happen if I ever manage to clear enough space in the workshop...
Anyway, all that's a little OT, but I do have a soft spot for these sets, and am keen to see some progress with this one. I haven't seen a schematic, but I'm fairly sure the 1820 used colour difference drive rather than RGB drive for the CRT (I remember that because I really wanted to install a teletext decoder, and that added to the complexity), so the 1800 likely did too. Not that that guarantees anything, of course - the fault could be anywhere.
I'm guessing the cabinet might be the biggest challenge. How has the wood survived the damp? Is it chipboard?
Over the years, I saw many 1820s, and all had tired CRTs, but the one I've kept is unusual as it's like new - pin sharp and bright. Good greyscale too - normally the tracking between guns goes bad as the tube ages, meaning compromises are required when setting up. I've seen lots of faults, but usually capacitors - the big blue film caps on the timebase board, normally. One thing that did help me fairly early on - there was a later PSU with over-current protection, so timebase faults in the set wouldn't then immediately take out the PSU. I don't care about originality - that PSU has been in my set for as long as I can remember, and has been invaluable!
I haven't powered it for 20 years or more, but I'm sure it'll work with minimal effort. It's been stored inside all that time I've owned it. I do have another, that was given to me about 7 years ago, and that has works well (apart from the usual soft CRT). It has a marginally better cabinet, so you can guess what's going to happen if I ever manage to clear enough space in the workshop...
Anyway, all that's a little OT, but I do have a soft spot for these sets, and am keen to see some progress with this one. I haven't seen a schematic, but I'm fairly sure the 1820 used colour difference drive rather than RGB drive for the CRT (I remember that because I really wanted to install a teletext decoder, and that added to the complexity), so the 1800 likely did too. Not that that guarantees anything, of course - the fault could be anywhere.
I'm guessing the cabinet might be the biggest challenge. How has the wood survived the damp? Is it chipboard?
