CRT Monitor just popped - worth fixing?

[CDTV1991]

I have a clone of the Commodore 1081 Monitor, called a "Highscreen KP548". In classic beige and a perfect picture for the Amiga.

Turning it on tonight and it lets out a continuous loud high-pitched scream and loud buzzing. I had to turn it off as it sounded like it was going to catch fire.

Does anyone where to start with investigating and fixing this?

I was really enjoying the CRT look again as its miles better than my BenQ BL702 LCD monitor and I may have to go back to that.

[zipper]

Probably LOPT giving up. Flyback transformer (FBT), also called a line output transformer (LOPT), the high voltage part that might be not easy to find.

[CDTV1991]

Ah, gutted.

Ever since the early 90s I always wanted a proper monitor for my Amiga. Made do with SCART TVs at the time, which was fine. In my more recent Amiga times I've used an old 14" CRT TV, which looks good.

If you could buy a new CRT for the Amiga, that would last 20yrs, then I'd buy one.

Seems like this one is dead, which is a shame.

[ptyerman]

Sounds like the LOPT is dead. Replacements are available if you do a search but the problem is getting it replaced. You DON'T want to touch that unless you know what you are doing. There is people on this board that would possibly do it for you but the main problem there is couriers, most won't transport second hand monitors or TV's.
There was two different LOPT's used in those monitors so you would have to get the part number off the old one before searching for a replacement.

[Hewitson]

Complete waste of time and money to repair.

Do yourself a favour and get a nice big flat screen Trinitron, they're so much better than the crappy old Commodore monitors.

[turrican9]

I would recommend a BenQ BL 702A or BL 912 with a RGB to VGA adapter. After tuning pixel clock they look great with Amiga.

[CDTV1991]

I have a 702A, the purple boot screen looks really blotchy. It's better when there's a pattern on screen. Is that a pixel clock thing or related to my A600 probably needing a re-cap or both.

Nowhere near as good as this CRT monitor, nor my 90s Bush 14" TV/VCR, which gives a nice picture.

[turrican9]

Originally Posted by CDTV1991

I have a 702A, the purple boot screen looks really blotchy. It's better when there's a pattern on screen. Is that a pixel clock thing or related to my A600 probably needing a re-cap or both.

Nowhere near as good as this CRT monitor, nor my 90s Bush 14" TV/VCR, which gives a nice picture.

Usually the sweet spot for the pixel clock is between 88 to 94. When you see no vertical lines on the blue whdload information/loading window the pixel clock should be correct. Also, finetuning the phase clock can improve it somewhat.

I've had many 14 inch CRT TVs with scart and for me the BenQ screens mentioned are much better. Also, CRTs have way too much flicker for me. Hurts my eyes.

[MartinW]

Clearly this is all personal opinion (LCD Vs CRT) but my opinion is that a CRT is going to be considerably better than the 702 and that I'd get it repaired if you can find someone local enough to take it on for you.

I say this purely because the 702 is very washed out compared to a decent CRT which will have a much more vibrant picture and way better blacks (hell it actually has black, the BenQ simply does not know what black is!) - and I also really miss scanlines on my 702. Obviously at some point in time we are just going to have to accept that LCD is the way it is going to be. I would be a LOT happier with my 2 702's if they had a decent IPS panel instead of the really poor TN panel that they have in them.

Regarding getting the original CRT fixed. I haven't touched monitors for years now so cannot help but when I did, the ones I was fixing would 9 times out of 10 pop other components as well when the LOPT died like the HOT for example (horizontal output transistor). But anyone that can take it on should know if other parts routinely need to be replaced too.

It would be worth first checking for cracked / bad solder joints in the HV area but I agree, it does sound like the LOPT has gone.

[turrican9]

It's all a matter of taste yes. But honestly, I think my 702As have very vibrant colours and does not look washed out to me. And the level of black is not an issue for me. I think black is black enough how I have it set. And I have compared to quite a few CRTs. Honestly, the 50Hz flicker alone is enough for me to stay away from CRTs for Amigas. Even back in the day my eyes would hurt after a few hours from CRTs on Amiga. Especially if I played any sort of adventure game where I had to read text.

The problem with a PAL Amiga is that for general use one are locked to 50Hz on a CRT which means horrible flicker. Even a CRT for PC at 60Hz is horrible flicker. One need about 85Hz for it to be more relaxed for the eyes. I am pretty sure that many people use glasses today as a result of stairing at CRTs all day long back in the day.

I have Indivision ECS/ECS V2 and AGA MK2 to add scanlines to my LCDs. Looks even better. But on the 702A I think it looks good even without scanlines.

But each to their own. I wanna keep my 42 year old eyes for many more years. I've tried so many CRTs the last few years because of nostalgic reasons and always get rid of them because of above mentioned. And they also takes up alot of space.

With that said, people using CRTs for retro have all my respect, but I'm just not hardcore enough for CRTs I guess

[CDTV1991]

Had some advice from a local repair company and it is likely to cost well over £100 to fix, so unfortunately it is not worth it.

[lost_lemming]

I had a 1084 that repaired and rescued just in time, the coppers wires on the yoke and burnt out (probably because it was stored away for a long time with moisture)
all the burnt wires had to be replaced.