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Old 11-27-2016, 03:52 PM
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wa2ise wa2ise is offline
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Quote:
Originally Posted by Kevin Kuehn View Post
A resistor in that position can act as a slow blow fuse if a filter cap shorts hard to ground. Before blowing it protects the power transformer from over current. Basically it acts as a shock absorber.
It also makes life a little easier for the vacuum tube rectifier. Lower peak currents due to the filter cap recharging between full wave cycles at 120Hz. You can kill a rectifier tube if you have too much filter cap and too low source impedance on it. SS diodes are much more forgiving here.
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