From mgarvi–(at)–anix.com Mon Nov 11 20:44:49 CST 1996
Article: 27182 of alt.guitar.amps
Path: geraldo.cc.utexas.edu!cs.utexas.edu!howland.erols.net!panix!news.panix.com!not-for-mail
From: mgarvi–(at)–anix.com (Mark Garvin)
Newsgroups: alt.guitar.amps
Subject: Re: Princeton & screen resistors
Date: 11 Nov 1996 20:14:03 -0500
Organization: PANIX Public Access Internet and Unix, NYC
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References: <32878CE3.52B--(at)--arthlink.net>
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>LC Krakowka wrote:
>>
>> The Princeton Reverb schematic doesn’t show any 470 ohm 1 watt screen
>> resistors. Would it be wise to add them? My amp’s an AB1270 circuit as far
>> as I can tell. TIA

In <32878CE3.52B--(at)--arthlink.net> Brad & Dona Bolton writes:
>Yes, indeed, add them. And make sure you use the 1-watters or better.
>This will prolong tube life and tighten up the sound some. The louder
>you play your amp, the more screen current flows, and teh more you need
>those resistors.

Correct, and I kinda like the adjective ‘tighten’ cause the screen
resistors do contribute some negative feedback.

I used to use higher wattage resistors sometimes, but I’ve been
sticking to 1-watters cause they’ll act like a fuse if something goes
wrong. Here is another place where carbon comps can react differently
>from carb or metal films: they’re much better at handling transient
over-wattage conditions. Unfortunately, I’ve seen them get lower in
value sometimes…not good for a screen resistor to do this.

MGarvin
NYC