Neotec 27E Troubleshooting

cpu.slave

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I'm working on my Rush - plays blind. When I pull the back off and power up, I get no glow from the tube, don't hear the static charge? that I normally hear when you power one up.

Checked all the fuses, made sure the chassis is getting power. Double-checked all the connections, reset and everything looks good. Reseated the neck board etc.

I seen this sort of work when I picked it up - thought the chassis might need to be capped. Since getting it home, it has never worked and I finally found some time to start looking at it.

Neotec 27E with a Zenith tube - Any ideas on what to check?
 
FYI. If the cap kit doesnt work theres one more thing that can be wrong. Theres a small 8 pin IC in the power supply area on the monitor chassis. Try replacing that IC.

Matt
 
I've finally found time to get back to this - and here is where I am- Now dealing with 2 separate 27E chassis-

First chassis - cap kit and flyback - still dead (and I'm not sure which IC - is it located at IC101?)

Second chassis - cap kit and flyback - just chirps.

I thought I could get at least *one* to work out of the pair, but no luck. After all the work on them, neither has changed at all. Any ideas what to look at next?
 
First chassis is totally dead? You can try pulling the IC in the power supply section out of the second chassis and putting it in the first one. Its the small 8 pin IC. Or you can swap the horizontal output from the 1st one to the second one since thats probably whats wrong with the second one.
 
First chassis is totally dead? You can try pulling the IC in the power supply section out of the second chassis and putting it in the first one. Its the small 8 pin IC. Or you can swap the horizontal output from the 1st one to the second one since thats probably whats wrong with the second one.

I have a additional spare chassis that was missing several parts, but had the IC - switched into chassis one - no change, still dead.

I'm a little new to this end, more into pins if you know what I mean, so is the horizontal output ?? That board on the side (which I capped as well?) or what am I missing? I have the manual in front of me but can't figure out what you mean - sorry.
 
The horizontal output is the three pin part mounted on the heatsink next to the flyback (looks to be about the size of a Tip36c).

Since the first board is still dead I'd look to see if your getting DC voltage past the bridge rectifier. Theres a large capacitor in the power supply section that will end up with 140-180DVC on it so if your going to look for voltage there be careful. If its there then theres something wrong with the switching section of the supply if its missing then follow the path backwards. Could also be bad caps in that section but you said you changed them right?

Monitors can be very scary to pin guys... You'll get it.

Matt
 
Ok - swapped horizontal output off of parts chassis - chirp chirp chirp chirp etc.... No change.

Yep, recapped everything, even the pincushion kit from Bob on both, replaced the flybacks and yet here I am back where I started, one dead and one chirping.

I'm going to take a step back from these because you're right - scary as well as aggravating. I'll come back and post an update after I have had a chance to go over it again and trace the power on the dead one to see if I can find anything wrong there - it might be a few days. And if I still can't figure it out, I'm about ready to throw in the towel and send them out to someone who knows this stuff way more then I.

Thanks for the help Matt.
 
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