coupling caps?

[EWBrown]

The 0.056 uF / 400V Russian Teflons are a more manageable size than are the 0.1 uF 400V ones, and could be used on the G*S*G in the same way that the 0.22 uF 1KV size K40u-9s were.

The Teflons do not have wire leads, just a silver plated soldering post on each end. These can take a fairly long time to properly "break in" and can sould a bit sharp or harsh for the first 100 hours or so.

/ed B

[EWBrown]

If working with all those leading zeroes gets a bit confusing, the formula can be further broken down thusly:

1,000,000 / (2*pi) = 159,155

this allows you to use microfarads instead of farads.

so, the -3 dB LF point, with a 0.047 uF coupling cap would be

159,155 / (0.047uf X 470,000 ohms)

or

159,155 / 22,090

or

7.205 Hz OK, Mister Spock, let's not be so Vulcan logical, and act a bit more human)...

7 Hz is more than good enough, we're not splitting atome here

If you like to work with uf and K ohms, then it would work out thusly:

The formula can be further broken down one more time, to factor in K ohms: 1000 / (2 X Pi) = 159.155

159.155 / (0.047uF X 470K ohms) or 159.155 / 22.09 = 7.205 Hz

Old school trick, to determine PI to a ridiculously good figure, from the days of the primitive "four banger" calculators:

remember the number 113355

divide 355 by 113 = 3.1415929

Actual PI = 3.1415927

Of course, for our purposes, 22/7 is more than good enough: 3.142857


/ed B

[Shannon Parks]

Ed, I bet you use an RPN calculator.

Shannon

[fran604g]

Pi is the easy part for me, it's difficult for me to comprehend the path of a signal being in and out of phase in degrees. I don't understand enough of the fundamentals to even begin to comprehend the engineering of even the simplist 2 stage amplifier. I read and read and read, but, life has it's distractions so I get nowhere pretty quick.

I appreciate the explanations, though, sonner or later it will all make sense.

Thanks again!

[EWBrown]

Great guess, I did use RPN calculators back in the day (the HP ones were the most notorious for this approach). I didn't actually own one back then, they were way too much money for a poor starving tech like i was back in the 70s THough the company I worked forbought a number of them for us to use as needed. I went through the series of TI scientific notation calculators once they became affordable (under $200). I still have them, though most no longer work, after nearly 40 years.

The real piece de resistance in the calculator world was the Wang Calculator, with their nixie displays, and remote operator "consoles" tied to the central processing unit. Great stuff for their day, back in the late 60s and early 70s, and definitely not consumer-priced.

/ed B

[Shannon Parks]

My boss and Thermion are RPN guys. I always need to make sure I bring my calculator when I am working with them. If they hand me their calculators (80's HPs), I am lost. I use Casio calculators.

http://www.youtube.com/watch?v=eSBybJGZoCU

Shannon

[fran604g]

Kraftwerk...now you're showing your age...

I'm glad you guys know what you're doing. RPN. Hell, I have enough problems with my TI-30XA. I'm a CNC machinist by trade so, really, I don't need to know much more than trig.

BTW, I am loving the Jensens (Angela's) caps, nice little improvement over the Russian .1's IMO. I probably should have tried the Russian .22uf's...I dunno, difference between the 2? Quite a few opinions out there. Anyway, I like 'em.

Thanks again for your help!