[Johnson] Adventurer filter caps

[Glen Zook via Johnson]

Although it is still a good idea to have equalization resistors across the capacitors, modern capacitors have much closer tolerances than in the "goode olde dayes".  Modern capacitors come in +/- 20% or +/- 10%.
I would use 450 volt capacitors just for the safety factor. Glen, K9STH

Website: http://k9sth.net
      From: Dennis A. Deaton <wa6acc at verizon.net>
 To: 'Charles Ring' <w3nu at roadrunner.com>; johnson at mailman.qth.net 
 Sent: Monday, March 2, 2015 1:27 PM
 Subject: Re: [Johnson] Adventurer filter caps
   
Charles,

A lot of guys use strings of lower voltage capacitors to replace the
700-Volt units found in these transmitters. In my Adventurer I've used three
33-uf / 350-Volt caps with 270K-Ohm / 1-Watt equalizing resistors around
them. The 1-Watt rating on the resistors is necessary because of the
200-Volt+ potential around them. Collins used this same string in the 516-F2
S-Line power supply. You need to use the equalizing resistors because
electrolytic capacitors have capacitance tolerances of -20% to +100% which
throws the instantaneous voltages across them all over the place.