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My fellow tech's...a diode question..

8/27/2003 12:03 AM
Jeff Seal My fellow tech's...a diode question..
I've got a RI ReverbRocket on my bench right now with almost dead shorted spike suppresor diodes... apparently second time this has happened..first time the amp's been here though...last tech changed two 1n4007 diodes, and now the other two have gone my customer is not gonna be real happy if it happens a third time....which I'm reasonably sure is going to I'm thinking about two options....removing the diodes entirely or adding a third diode to each bank...for a total of six...any thought's or suggestion's...  
Thanks in Advance,  
8/27/2003 9:00 AM
Chris ( CMW amps )

Hi Jeff  
The best thing you can do ( imho ) is to remove them ( they also do effect the sound somewhat ) , lots of old Ampegs did have a 250 ohms / 15 Watt resistor at the OT-output and that's a way better protection .  
Good luck / make your customer happy !  
8/28/2003 4:53 AM
Jeff Seal
Thanks, Chris....that's pretty much what I've been doing in the past, but thought I'd get some differing views on the subject.....two heads are better than one....  
Jeff Seal
9/3/2003 8:03 PM
Rick Erickson

In leu of removing them I would use a fast recovery diode. The R2000F from Mouser (p/n 583-R2000F )works great. Use two in series on each side of the o/t primary. I don't know if anyone has ever taken my advice on this subject but it has been my experience that a standard 1N4007 is not fast enough to recover from the inductive "bounce" when the o/t kicks back. I have put these diodes in many amplifiers and not had any failures yet.  
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