SOLD Blast city

[Revrun91]

I have a blast city that I am looking to sale. I am located in Moncks Corner, SC. It perfectly works 100% I can happily give more video and pictures of condition and with it on. MS-2930. I recently just changed the buttons from sanwa to Baolian. Last picture is most recent.

Asking $1800. Buyer must arrange shipping.

 

[Revrun91]

*sold*

 

[bergalon]

Nice price! My two from you are still dead lol.

 

[advans14]

happened?

 

[Revrun91]

The two I sold him needed chassis recap and/or CRT rejuvenation

 

[bergalon]

The two I sold him needed chassis recap and/or CRT rejuvenation

I have no idea what's up with them yet and am still working on getting them going. Pics and messages rev sent showed working but with 1 dim and 1 missing blue (?) but they just go into HV shutdown immediately. I did have some blown out image on one for a few minutes so at least one tube has some life! They did travel 11hrs on the road so who knows. We were stupid and didn't see them working at pickup. Don't be dumb like me!

Full recap on both and now I'm working on finding other issues. Nothing obvious thus far (2931 manual offers nice guidance). Interestingly one had wrong chassis (2931 tube with 2930 chassis) which has wrong yoke impedance and could be what caused dimness. No mention of needing rejuvenation was made until after pickup but that's probably what he meant by dimness honestly. Other than that they look pretty and I got a d9400 that I'll try at some point since I think it can be "back mounted".

On a side note anyone want a nonworking 2930 chassis for a perfect 2931?

I know he's sold lots of these so I'm sure it's just bad luck. Sorry to imply otherwise if I did.

 

[Anselmo]

2931 Tube with a 2930 chassis have worked just fine for me. I think the 2933 tube might have a dimness issue with a 2930 chassis.

 

[MegaShock-76]

If it's going into HV shutdown, it's trying to protect the tube from high voltage. Some dont go into shutdown mode and crack the neck rendering the tube iseless. Chassis may need a flyback. Just my opinion.

 

[bergalon]

If it's going into HV shutdown, it's trying to protect the tube from high voltage. Some dont go into shutdown mode and crack the neck rendering the tube iseless. Chassis may need a flyback. Just my opinion.

Out of the three chassis I have all give the same impedance between pins on the flyback. Aside from that simple test (and checking for cracks and such) I don't have any magic way to check what's up. At the moment I just want to build a lightbulb so I can test B+ and some other things.

 

[bergalon]

2931 Tube with a 2930 chassis have worked just fine for me. I think the 2933 tube might have a dimness issue with a 2930 chassis.

Thanks for this! My 2930 and 2931 tubes have different yoke impedance values and I was just guessing from some stuff Mike mentioned on his "amateur" youtube channel and the Otaku site that maybe that's why one was "dim". I haven't gotten it ever to even give neckglow though. If a simple set of tests don't get me anywhere I'll probably 1) get a rejuvinator to rule out tube issue (although I'm getting zilcho on G2, etc at the neck so I'm thinking this is unlikely). 2) If all else fails I'll send it to Sharp or PNL

 

[GeekMan1222]

These chassis's are known for flyback issues. You could check the impedence of the windings for the flyback sure but its still not under load etc.

That said flybacks are worst case scenario these chassis's have multiple incorporated safety shutdown modes and anything out of line will immediately shut the chassis down from the switching PSU. The flyback and HV is also driven from an entirely seperate HV generation block with its own mosfet purely for driving the flyback only. If anything in that block is bad then the flyback wont run and you wont get heater voltages etc and then then chassis would probably shutdown totally too.

These are not easy chassis's to work on a deeper board level, you can cross reference the 2931 service manual for better clues since the 2930 and 2931 are pretty much the same chassis's but they DO have changes and revisions so schematics and things you cant take at 100% face value.

When these chassis's are in good fit and health they run very well though its just a shame that they trigger to shutdown so easily and the complexity of troubleshooting it.