- Thread starter BlinG
- Start date
It sucks man. I'll probably just take the money I get from selling this and put it towards getting another cab from KC. Next time I think I'm gonna lean towards the ms2930 with manual sync. They seem to be more reliable than the 2931. My other blast city has a 2930 and it's still going strong.
All Net Cities come with 2931. You mostly see them with original monitors, so I would say they're at least as reliable as the 2930. It's just luck of the draw with these things.
Personally I prefer analog adjustments to OSD controls.
Personally I prefer analog adjustments to OSD controls.
You're right, I forgot about it. The chassis is very uncommon though. Personally, I've never come across one.
sorry to necro but I had this issue with my 2930 when I still had a Naomi connected to the vga but wasn't being used. I disconnected the Naomi and the dimness went away. My jamma came through bright and colorful.
I didnt have anything connected to the VGA port on the chassis, so unfortunately that wasn't the issue. I eventually just bought another Blast that came with a 2930. I don't think I'll ever go back to the 2931, just too much of a headache when it starts crapping out.
Hatsune Mike
Champion
Tubes go dim and reach end of life for emissions, and how fast can depend on the heater voltage, runtime of the tube, and manufacture aspects/quality of the tube itself. 2930, 2931, and friends all seem to reach low emissions faster than many other tubes of similar vintage, but it happens to any tube with a lot of use.
If the tube isn't too far gone, then a light hit with a Rejuvinator's Restore function may bring a lot of life out of a tube. If a tube is really far gone, though, then a restoration or even full rejuvination likely won't get more than a couple hundred hours of the tube before it goes back. Your mileage may vary. I've hit some medium-dark tubes with a very light restore and had them run bright and sharp for even years after, while another lasted only a week of daily 9-5 runtime before going dim again. It is worth a try as a relatively cheap option.
If the tube isn't too far gone, then a light hit with a Rejuvinator's Restore function may bring a lot of life out of a tube. If a tube is really far gone, though, then a restoration or even full rejuvination likely won't get more than a couple hundred hours of the tube before it goes back. Your mileage may vary. I've hit some medium-dark tubes with a very light restore and had them run bright and sharp for even years after, while another lasted only a week of daily 9-5 runtime before going dim again. It is worth a try as a relatively cheap option.
I'm having this exact issue on my blast I just in. When I hook my tester up to the tube it say all three guns are either dead or close to it. When I rejuve them the last gun I do it on is showing like 110% good but the other two are dead. When I run the game it is literally only one gun firing. If I go back and just clean and balance the guns a couple of time it goes back to the super dim but all three guns are at least running.
Edit chassis is ms2931 tube is a68lbt696x
Edit chassis is ms2931 tube is a68lbt696x
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This may be of interest:
http://www.ukvac.com/forum/nanao-ms2933-chassis-on-ms2931-tube_topic368207.html
As taken from the thread in question, if the chassis has been swapped at some point then you may experience some issues with dullness. The 'fix' is to replace the 3 Ohm in position R732 to a 2 Ohm resistor.
http://www.ukvac.com/forum/nanao-ms2933-chassis-on-ms2931-tube_topic368207.html
As taken from the thread in question, if the chassis has been swapped at some point then you may experience some issues with dullness. The 'fix' is to replace the 3 Ohm in position R732 to a 2 Ohm resistor.
I'm having similar problem but I went from a 2930 to a 2931.
Hatsune Mike
Champion
Pretty sure that resistor is just changing the heater voltage on the tube, which is a last-ditch way to get more emission out of an EOL tube.
Hatsune Mike
Champion
Which part was shorted? I have had some good luck removing G1 and H-K shorts with my Sencore CR70.
Hatsune Mike
Champion
Did you check for G1 shorts though?
mine was solved it was the b+ pot. They had turned it down when sharp repaired it. Iv never messed with that pot because I have bad luck. But the glue was removed so I baby stepped it.
Yes I did, no shorts were showing on the 480
So one of my MS2930 chassis recently crapped out. I replaced it with a MS2933 as above. I have the same issue, dim screen.
I rejuvenated all three guns as they were all showing poor. I have the contrast turned up to max, and most of the gains as well. It looks OK now, but nowhere near as bright as with the 2930.
Shame there's no easy way to measure the heater voltage. Would be interesting to know if the tube is now undervolted or if it was overvolted with the 2930.
Here's a schematic for a CRT heater voltage meter if anyone here is up to building one:
https://elektrotanya.com/files/forum/2014/03/kepcsofutes-mero_[ET].pdf
