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Re: L & C measurements cheaply, how?
From: Scott Stephens[SMTP:stephens-at-enteract-dot-com]
Sent: Tuesday, December 30, 1997 2:36 AM
To: Tesla List
Subject: Re: L & C measurements cheaply, how?
At 01:57 AM 12/27/97 -0600, you wrote:
>I am curious how most of you are measuring L & C's for homemade tesla
>components. I am looking for an inexpensive way.
>Someday, I'll save up for a scope & func. generator, but now I just need
>something cheap and convenient.
Build a signal generator using a transistor, coils & cap
calibrate using AM radio.
Better yet, build it using 4011 CMOS NAND gate, 2 RC oscs, 1 at audio, the
other at RF, and modulate the RF with the audio.
Since cap's have poor tolerance, callibrate using AM radio.
Of course if you had test equipment, you could just hak the radio.
Now build a diode detector, and use a meter to measure the 3dB points of
your coil or cap. What value resistance has 1/2 the voltage dropped across
it at that frequency?. A frequency counter would sure be nice. And a scope too.
If you know the coil diminsions, bandwidth, and center frequency, you can
calculate L,C and Q.
I want to build a combination signal generator, complex (S-Parameter)
impedance/L/C meter, and spectrum analyzer that interfaces to PC's or TV's
using about 3 chips and cost under $20.
No one on the PIC microprocessor list was interested. Or sci.electronics. So
its not worth enough money for me to deal with.
I'll go back to building my coil.