So, when I power up my amp, I see 3910vdc on my plate. The way I have it configured, I put 330vdc on the screen grid and -130volts on the control grid., when I bring the control grid to -69v, the tub
Chuck, Really, you use the peak voltage (open circuit voltage), and the peak current (current under load at peak power) with the formula below; Ra = Va / (1.8 x Ia) Ra = Plate impedance in ohms Va =
No, the voltage and current of the amp when it is running at what you plan to operate it at are the values that you plug into the formula. Say that the voltage drops to 3500 volts at an operating an
ok.... one guy says use the "open circuit voltage" the other guy say use the loaded "operating voltage" ..................who is correct _______________________________________________ Amps mailing l
yea... what he says LOL I'll work the inbetween and see what happens in real life. ~chuck ________________________________ ok.... one guy says use the "open circuit voltage" the other guy say use the
We are trying to match 50 ohms to the tube plate under full power output conditions for the class of operation. Full power output happens with full drive, maximum plate current and whatever plate vol
BTW, on the discussion of k=1.8 vs. 1.87 in the calculations: There is less than 4% difference between these two values. The difference can be covered by only a small "tweak" of the loading and tunin
Assuming you're making an adjustable matching network, you should be able to match a range of tube impedances while maintaining network Q within 12-15. Use your program to do some preliminary runs an
Gary, Well, some books say "applied voltage". Matter of fact, I myself asked this same question on here a good while back. The answer I got from a regular on here was "peak everything". Look back in
ORIGINAL MESSAGE: ** REPLY SEPARATOR ** There is a simple way to add ten meters when there is too much C. See any recent ARRL handbook for details. It is nothing more than adding a single coil to for
Author: Peter Chadwick <g3rzp@g3rzp.wanadoo.co.uk>
Date: Sat, 1 Apr 2006 13:03:31 +0200 (CEST)
You have to figure on the supply volts under load. Let's assume we're in AB1 for an example. From the tube data sheet, we can choose the plate voltage when the grid volts are zero - usually just abou
Peter, I can't make this information agree with practice. For example, I have a TH347 amplifier on 23cm that runs 3000vdc at 1.8A on the plate. Conventional design would yield a plate impedance of 92
I think that Peter inadvertently left out a factor of 2. According to my RCA tube manual Rp is equal to twice the plate voltage swing divided by the max current. David KC2JD --Original Message-- From