Is it possible to put a 2watt 220k resistor between each of the terminals of the screen/pi can to ground?
Or just on the screen side?
Would this work like on the 100w amps?
Would it make the amp self draining?
Screen and PI Filter Resistors?
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Re: Screen and PI Filter Resistors?
yes, but the resistor should handle 500v or so. and it will change the preamp slightly. If you add a 220k bleeder at v1's filter cap, the ground potential of v1 is not any longer 1m with 1m vol pots, but rather 1m in parallell with 220k bleeder in series with the 100k plate resistor. the ground potential is then around a quarter of what it used to be.
I'd try two 220ks in series
I'd try two 220ks in series
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Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
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Super 100 amps: 1202-119 & 1202-84
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Re: Screen and PI Filter Resistors?
I never thought of it like that! Do you find that it changes the tone of the amp?
I use 270K 5W directly after the rectifier normally. The main reason for using 270K 5W is I have a bag of them and no other use for them!
I use 270K 5W directly after the rectifier normally. The main reason for using 270K 5W is I have a bag of them and no other use for them!
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Re: Screen and PI Filter Resistors?
yes, the effect is similar to using a 250k volume pot. I prefer the vol pot to read at least 500k. Lower reading pots can reduce noise and gain, something that can be useful on high-gain amps but hardly on plexis
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Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
http://www.myspace.com/prostitutes" onclick="window.open(this.href);return false;
Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
- neikeel
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Re: Screen and PI Filter Resistors?
Most agree that old plexis sound best with high reading >1M volume pots
Neil
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Re: Screen and PI Filter Resistors?
yes, another reason for being careful with those 56k screen bleeder resistors. 220k or 330k works well
http://www.myspace.com/20bonesband" onclick="window.open(this.href);return false;
http://www.myspace.com/prostitutes" onclick="window.open(this.href);return false;
Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39
http://www.myspace.com/prostitutes" onclick="window.open(this.href);return false;
Super 100 amps: 1202-119 & 1202-84
JTM45 RS OT JTM50 JMP50 1959/2203/34/39