Hoffman Amplifiers Tube Amplifier Forum
Amp Stuff => Tube Amp Building - Tweaks - Repairs => Topic started by: schoolie on January 11, 2012, 04:29:11 pm
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Hi, could I use two of these NTE diodes in place of the normal six 1N4007 diodes, in front of my GZ34 tube? This is insurance, but I might also make a switch to choose solid state or tube rectifier later.
They are rated at 1A and 1500V. My secondaries are around 325V from the CT. I think these are OK and I can buy them locally, but haven't heard any mention of them on amp forums. Does anybody use them here?
Here's a link to the specs:
http://www.nteinc.com/specs/500to599/pdf/nte558.pdf (http://www.nteinc.com/specs/500to599/pdf/nte558.pdf)
Thanks!
Rob
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Those seems fine
if you want to have a Tube / SS rectifier switch, use the schematic at page 8 of this file
http://home.comcast.net/~seluckey/amps/misc/Amp_Scrapbook.pdf (http://home.comcast.net/~seluckey/amps/misc/Amp_Scrapbook.pdf)
courtesy of Sluckey
don't try to exclude the Tube switching between PT and rectifiers, this will short the life of your Tube rectifier
Kagliostro
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Thanks, Kagliostro! And also thanks for the link--what a treasure of useful information!
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You can use those.
From one distributor, they cost $2.59/ea vs $0.04/ea for 1N4007.
The NTE558 probably has a much faster recovery time, which I suspect because the 1N4007 datasheets I've seen won't even mention reverse recovery time.
However, the 1N4007 is more than capable for your amp. 325v*1.414= ~459v, *2 = 919v.
But you can always pay more if you feel the part is worth the cost difference. I'm presently paying more for some resistors and pots for an amp build, but just because I really want to try the parts to have an informed opinion of them.
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Thanks, HotBluePlates! They are only $1.69 at my local store and I wanted to spoil my amp :laugh: They are the same size as the 1N4007s. Pretty nifty. For some reason, I remember reading that the diodes should be rated above 1200V , but yeah, 1000V should be fine.