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Science advances not by repetition of experiments and analysis of large amounts of data, but by carrying out that one crucial test / experiment that refutes present knowledge. With proper research

Mine's on the shelf in front of me. Vince - K8ZW. -- Michigan VHF Corporation -- nobucks dot net https://www.nobucksboutique.com http://www.metalworkingfun.com K8ZW - http://www.hamradio.fun

Some of us remember how to use a slide rule, accurate to 3 places - maybe. Paul, W8AEF _____ From: [email protected] [mailto:[email protected]] On

I had a good measurement 9,985,727Ω for a 10MΩ resistor. The manual suggests using low capacitance for large resistors and high cap for smaller resistors. I also use a lower Q inductor at about 232.

Jeff, trust me, engineering *is* an art, the art of compromise between what one wishes to achieve, what technology (&c.) permits, how much it's all going to cost (and how long it might take &c.), and

Using an LF coil at lower freq, with the nominal 98 megohm, results are not good.? 459 x 448 /? 2? pi? 159,269? 450e-12? 11 =? 41.512 megohms

On the idea perhaps the resonating capacitance was too small compared with any (tiny) inductance of the resistor, I resonated at the other end, using 450 pF, using the nominal 98 Mohm. 1447 x 1423 /

By standard, is that 10MΩ Is that thru hole? That 5MΩ is about what I got when I was using a thru hole. I think--- maybe, just maybe I found the answer. If you look at section about measuring "Large

I tried again, this time with four 22 megohm in series with 10 megohm for a nominal 98 megohms total. 1700 kHz, 32.3 pF, coil-alone Q 990; with resistors Q 850.? 990 x 850 / 2? pi? 1.7e6?

I tried it with my HP4342A Q meter, and a standard 5% 10 megohm resistor which measures about 10.97 megohms on my Fluke 87V. (The reading keeps creeping up, never seems to finally stop....) 1700 kHz,

Would some perform this experiment on their Q meter? I continuously get a about a 19%? low error. I have used two different Q meters. I'm attaching thin wires to an 0805 resistor. But please use what

I have seen that before, I thought it was in the Files section, but I don't see it. I put the scope on my Ringdown Meter to look at the waveform. It gets a shake and ringsdown, at some point It gets

The ring-down technique for measuring Q was new to me. I found this: https://www.giangrandi.ch/electronics/ringdownq/ringdownq.shtml 73, Leon G1HSM

I received the Ringdown Q meter Kit and have got it built into a case and working. The frequency range is 400kHz to 9.2MHz. Minimum inductance is 10uh, but I have 9.2uh and it worked. Here are some

wrote: That sounds great. A lot of people, myself included, enjoy trying to make something better, even if we don't *really *need it. That's good enough for most things. I have 6.5 digits, and that's

I would agree that all the LCR meters I have seen may be good at measuring LCR but really bad with Q accuracy. My point to Jeff was if he needed a wider range of frequencies or range of Q, get

Yes Jeff, metal film resistors can be spiral cut during trimming. But the inductance increase is usually very? small and in series with a much higher resistance. The inductance of a wire ended

Jeff, general purpose round-bodied metal film (MF) resistors will often have been trimmed with a spiral, but there are absolutely no guarantees with this. Specialist resistors are usually trimmed

I don’t think any LCR meter is particularly good at Q above 20. I have an HP 4285A (75 kHz to 30 MHz. Basic accuracy 0.1%). There’s an example in the manual of the uncertainty of a Q measurement

Saw a couple of HP 8640Bs in there.............