[Boatanchors] selenium rectifier replacement

[jhhaynes at earthlink.net]

There is an article in the January Antique Wireless Association
magazine on this topic - with the same advice as others have
offered.  Replace with a 1N4004 at least, and you might as well
use a higher voltage 1N4007 since the cost is only pennies more.
Always add a resistor in series, to reduce the surge current into
the filter capacitors.  A rule of thumb is to have the resistor
drop 10 volts; but you can play with the resistor value to get
whatever the voltage is supposed to be, if you happen to know that.

And he says always replace the selenium rectifier, even if the
equipment seems to be working OK, and not to use even NOS
selenium rectifiers because they don't improve with age.



jhhaynes at earthlink dot net