In Reply to: These 300B came in today and they Tube DIY asembled but didn't work posted by Michael Samra on April 12, 2014 at 20:00:29:
Hi Michael,
Just a note, there is no SCR (Silicone Controlled Rectifier) in this.
If you need help trouble shooting, drop me a line.
The Mosfet's on the Main Power Boards (IRF830 for +B and some 500V Fairchild P-Channel ones for the -C - sorry I forgot the part number) are a bit fragile. When they go usually the SMD LED's too go as do a lot of other 2 and 3 legged fuses on the boards.
If something blows up, best action is to completely re-build the boards, with all semiconductors replaced.
Also,try Raytheon 5687WB as driver and real WE 310A/B as Input Tube.
For rectifier I like brown base Coke Bottle 5R4G best, not greatly fond of the Chinese GZ34 that seem to be fitted, the Shuggie 274B is also a decent rectifier choice.
Best 300B to my ears in these where Full Music and KR/Vaic.
When in good nick and with decent tubes you should get around 15-16W RMS out of these Amp's, Class A2 past maybe 12W...
Thor
At 20 bits, you are on the verge of dynamic range covering fly-farts-at-20-feet to intolerable pain. Really, what more could we need?
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Follow Ups
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Thorsten 11:26:51 04/13/14 (6)
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Michael Samra 13:35:55 04/13/14 (5)
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Thorsten 13:42:56 04/13/14 (4)
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Michael Samra 13:52:15 04/13/14 (3)
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Thorsten 14:02:05 04/13/14 (2)
- I figured out why the loud buzz on the one amp when pulling off the grid cap. - Michael Samra 00:34:05 04/14/14 (0)
- RE: These 300B came in today and they Tube DIY asembled but didn't work - Michael Samra 14:50:32 04/13/14 (0)