Yeah, the first batch I was able to measure the pins and noticed the tube was shorted, by then the board was a bit "worn out" from messing around a lot trying to find the problem, second batch it all seemed fine on the pins but when I put it together it blew a mosfet instantly, it could be that I broke them installing, I don't like the design overall because it appears to be quite frail, then went with my known working but not as suitable 900v mosfets and the CCS's blew, then decided to get new tubes again, new CCS's still on the 900v mosfets and worked no problem. I'll look into going to the recommended mosfets again later, I also need to get some better trim pots, the ones I have make it very tricky to set the bias, not sure if it's normal?
Certainly thanks to you that I got it working again, was quite interesting, ever seen a 5842 at 450v? It's like a beautiful red flashlight
Try 6C45Pi if you don't mind messing with the 5842 pinout, it's the same tube with different pins afaik, I think still made too. There is a guy on here who modified the design significantly and you can use his schematic and go with 6SN7's which is still made as well.
Certainly thanks to you that I got it working again, was quite interesting, ever seen a 5842 at 450v? It's like a beautiful red flashlight
Try 6C45Pi if you don't mind messing with the 5842 pinout, it's the same tube with different pins afaik, I think still made too. There is a guy on here who modified the design significantly and you can use his schematic and go with 6SN7's which is still made as well.
After about 10 - 15 hours or so this happened to me:http://www.diyaudio.com/forums/tubelab/137329-tubelab-simple-se-fuse-blowing-2.html
One diode measures 99/94(depending which way around) and gets there quickly when I set it on the diode test, the other one gives a 821 one way and nothing the other...
I don't know if the tube sparked, I didn't see, music just went dead, saw the fuse was blown then decided that before I replace it to neaten up the wiring, so I powered it up with a new fuse and no tubes, kept on blowing fuses, R5 got quite hot at one stage so I thought must be the FRED diodes.
Solution new diodes and a new rectifier tube or is there something else to look into?
One diode measures 99/94(depending which way around) and gets there quickly when I set it on the diode test, the other one gives a 821 one way and nothing the other...
I don't know if the tube sparked, I didn't see, music just went dead, saw the fuse was blown then decided that before I replace it to neaten up the wiring, so I powered it up with a new fuse and no tubes, kept on blowing fuses, R5 got quite hot at one stage so I thought must be the FRED diodes.
Solution new diodes and a new rectifier tube or is there something else to look into?
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Another problem, figured I'll do the checkout again since I put new wires in, problem is with the output filament supply, 8.9v instead of 5...
I am using this: http://www.vishay.com/docs/94328/94328.pdf and this http://www.sharpsme.com/webfm_send/611
Measuring Pin1:8.9v, Pin2:8.9v, Pin3:ground, Pin4:2.27v, Pin5:8.9v
Any ideas?
I am using this: http://www.vishay.com/docs/94328/94328.pdf and this http://www.sharpsme.com/webfm_send/611
Measuring Pin1:8.9v, Pin2:8.9v, Pin3:ground, Pin4:2.27v, Pin5:8.9v
Any ideas?
How about this?
https://secure.cedist.com/scripts/f.../elevclients/cedist/ELEVATOR.FXP?item=T-SSR01
But I don't want a stand-by switch, is there an automated delay solution?
https://secure.cedist.com/scripts/f.../elevclients/cedist/ELEVATOR.FXP?item=T-SSR01
But I don't want a stand-by switch, is there an automated delay solution?
Ignore this stupid post, I suppose if I isolated the components when I mounted them on the large heatsink I wouldn't have seen this problem.
Found a soft start, bought a solid state rectifier and the soft start... Will report back if it all works ok.
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