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Old 13th Oct 2014, 10:25 pm   #95
Phil G4SPZ
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Join Date: Apr 2005
Location: Bewdley, Worcestershire, UK.
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Default Re: Roberts RMB Problems

Quote:
Originally Posted by Herald1360 View Post
...it now sounds like the original 1N4007 incarnation with two diodes was correct so why the low voltage?
Yes, that's baffling me too. The forward voltage drop of a silicon diode is generally assumed to be lower than that of a selenium rectifier, and it's common to have to insert a resistor to drop the excessive voltage produced by the diodes, not the other way round. The photo in post #92 clearly shows a coiled-up length of resistance wire which may have something to do with it. Until Dave comes back with the results of his latest tests, we'll just have to be patient
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Last edited by Phil G4SPZ; 13th Oct 2014 at 10:26 pm. Reason: Clarification
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