Have you looked into inexpensive scope programs that read your sound card in your computer? And display the waveform on your screen?
Those hand held meters are relatively accurate both for voltage and frequency measurement, especially at low frequancy. The ones I've used have resonators to set the gate period so they won't be super accurate but at frequencies up to 50KHz they should measure within a few Hz.
I don't think there's much difference between cheap models, they are all probably the same machine in different disguises. Brian.
Many years ago when I had no money and had to get by without much in the way of test equipment, what I would have done was to use a 10K resistor on the end of my live lead and measure all the DC voltages. Then stick a screwdriver into the coil (this stops the circuit oscillating) and re-measure the voltages. if the figures are different then it was oscillating! Now that solid state diode have been invented, use a germanium diode to earth, a .1 MF coupling capacitor to the live RF and again a 10K to measure the voltage or very low currents (50 micro A), this actually measures the peak RF voltage. With these sorts of circuits it is important that hooking your test gear onto the circuit does not stop it working.
Frank
If the voltage is too high, you can always drop it with a potential divider, the voltage will drop but the frequency should remain the same.
Brian.
Given the size of your coil, all you need is a much larger piece of metal, or a short circuit loop of copper wire. The copper wire will alter the frequency a lot, say from 100KHz to 5 MHz, but if your loop gain is high enough it will continue to oscillate. To stop upsetting fragile circuits use a 10:1 scope probe on your counter - 10 M ohms shunted by 10 Pf or less, if it upsets your circuit, redesign the circuit, its not a good design.
Frank
I was about to build a simple RF probe to connect to my old multimeter, but I see where the newer multimeters can measure frequency. But, before I invest in one, I am wondering how good a hand-held meter is for frequency measurements. I am going to build my first simple oscillator and I want to have a way to test whether it is oscillating, etc. I am assuming I can do this by looking at the voltages in the circuit with an RF probe.
This is just a hobby circuit, so I don't need super accuracy. I am trying to build a Colpitts oscillator to give me about 20-50k Hz. Thanks.
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