Hatsune Mike
Champion
tl;dr: my MS-2933 chassis clicks and goes into shutdown immediately.
I got a Blast City locally for next to nothing. Unfortunately, the MS-2930 had experienced a classic failure mode and had managed to neck itself with an HV spike or something like that.
It had a completely ruined tube and a broken MS-2930 so I temporarily mounted an MS9-29 with some standoffs to offset the tube back in the cabinet. The Blast was free for a reason!
I've used it this way for quite a while, and my main gripe with it is that it doesn't mate with the bezel properly. Otherwise, it works great, and it's no secret that I am enamored with the MS9-29.
However, I recently managed to get a suitable tube - that is, one that physically fits the Blast - by way of a Sanwa 29E31s monitor. The tube was pretty dim and tired, but it had no burn. I did a very light "restore" with a CR70 rejuve and the tube went back to being crisp with great contrast and sharp focus. I wrote up the process here.
The Sanwa 29E31s has a tube that's more or less physically the same as the typical Toshiba A68K**696X tube you'd find, but the yoke is around 0.30mH horizontal. As such it's basically the same as MS9-29 but the use of pin 4 on the neck means you cannot just swap that chassis in without consequences. However, the Toshiba PD9929 and similar ones from the New Net City monitor mate to it quite well and handle pin 4 properly. So, I used one of those chassis with some adapters I made for the various connectors. This worked and I was in business, and I did not even need to move any yokes around. It is worth mentioning that the 0.20mH Nanao yoke does pair perfectly with the E31s tube, and vice versa. I've done it in the past.
This is the E31s tube paired with PD9929 (running a Super Famicom though)
However, this PD9929 has always been a little janky. The horizontal has twitched a tiny bit at times, with the size experiencing slight variation. Furthermore, some coil or transformer tends to whine a lot, even after I've gone over all the solder joints a few times and tried mechanically dampening some of them. Between that and the menu system I have a pretty low opinion of these Toshiba chassis.
Last night while testing a JAMMA board the monitor suddenly went dark and into a cycle of clicking repeatedly between some upset buzzing noises. I have a hunch the HOT has died.
I got really concerned and wondered if my just-installed burn-free tube had necked itself. However, I don't see any Neck Lightning so I am hoping that's not the case. However, I still have the MS-293x yoke from the dead tube, and an MS-2933 chassis that I got non-working a while back.
The MS-2933, has a different flyback than the MS-2930 and MS-2931, and doesn't have a reputation for killing tubes or having the flyback die. If possible I'd like to just fix this chassis and use it and be rid of this Toshiba Turd.
The MS-2933 doesn't work though. When I got it, the HOT was shorted, as well as the diode near it that is bolted to the heatsink. Through replacing those I got it to the current state. Upon receiving power, it clicks, B+ briefly gets expected voltage, the LDO kicks in and briefly gives 9V to the low voltage section, and then it clicks again and goes into protection. I am testing it on the bench with the HV fuse removed so for now the flyback and HV are not part of the equation at all. You can test these Blast chassis by removing the HV fuse and putting a yoke on the bench. If it's working, it'll run "blind" like this, and you can debug the power, deflection, and amplification circuits before worrying about HV.
In any case, here's what I've done to the MS-2933 so far:
I am wondering if anyone has had direct MS-2933 experience and has any input.
I got a Blast City locally for next to nothing. Unfortunately, the MS-2930 had experienced a classic failure mode and had managed to neck itself with an HV spike or something like that.
It had a completely ruined tube and a broken MS-2930 so I temporarily mounted an MS9-29 with some standoffs to offset the tube back in the cabinet. The Blast was free for a reason!
I've used it this way for quite a while, and my main gripe with it is that it doesn't mate with the bezel properly. Otherwise, it works great, and it's no secret that I am enamored with the MS9-29.
However, I recently managed to get a suitable tube - that is, one that physically fits the Blast - by way of a Sanwa 29E31s monitor. The tube was pretty dim and tired, but it had no burn. I did a very light "restore" with a CR70 rejuve and the tube went back to being crisp with great contrast and sharp focus. I wrote up the process here.
The Sanwa 29E31s has a tube that's more or less physically the same as the typical Toshiba A68K**696X tube you'd find, but the yoke is around 0.30mH horizontal. As such it's basically the same as MS9-29 but the use of pin 4 on the neck means you cannot just swap that chassis in without consequences. However, the Toshiba PD9929 and similar ones from the New Net City monitor mate to it quite well and handle pin 4 properly. So, I used one of those chassis with some adapters I made for the various connectors. This worked and I was in business, and I did not even need to move any yokes around. It is worth mentioning that the 0.20mH Nanao yoke does pair perfectly with the E31s tube, and vice versa. I've done it in the past.
This is the E31s tube paired with PD9929 (running a Super Famicom though)
However, this PD9929 has always been a little janky. The horizontal has twitched a tiny bit at times, with the size experiencing slight variation. Furthermore, some coil or transformer tends to whine a lot, even after I've gone over all the solder joints a few times and tried mechanically dampening some of them. Between that and the menu system I have a pretty low opinion of these Toshiba chassis.
Last night while testing a JAMMA board the monitor suddenly went dark and into a cycle of clicking repeatedly between some upset buzzing noises. I have a hunch the HOT has died.
I got really concerned and wondered if my just-installed burn-free tube had necked itself. However, I don't see any Neck Lightning so I am hoping that's not the case. However, I still have the MS-293x yoke from the dead tube, and an MS-2933 chassis that I got non-working a while back.
The MS-2933, has a different flyback than the MS-2930 and MS-2931, and doesn't have a reputation for killing tubes or having the flyback die. If possible I'd like to just fix this chassis and use it and be rid of this Toshiba Turd.
The MS-2933 doesn't work though. When I got it, the HOT was shorted, as well as the diode near it that is bolted to the heatsink. Through replacing those I got it to the current state. Upon receiving power, it clicks, B+ briefly gets expected voltage, the LDO kicks in and briefly gives 9V to the low voltage section, and then it clicks again and goes into protection. I am testing it on the bench with the HV fuse removed so for now the flyback and HV are not part of the equation at all. You can test these Blast chassis by removing the HV fuse and putting a yoke on the bench. If it's working, it'll run "blind" like this, and you can debug the power, deflection, and amplification circuits before worrying about HV.
In any case, here's what I've done to the MS-2933 so far:
- Thoroughly checked over and reflowed solder joints as needed
- Checked relevant fuses and ensured AC is reaching inlet
- Watched B+ power come in at least momentarily
- Replaced HOT (Q511) and corresponding diode (D511)
- Replaced Q952 MOSFET (Q952) that is related to H. Deflection
- Replaced U451 vertical deflection IC
- Replaced Q901 in power circuit
- Replaced U901 power control IC
I am wondering if anyone has had direct MS-2933 experience and has any input.