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How are you calculating the Q of the capacitor? Mikek -- Thanks, Mikek

Yesterday's post using SimSmith to solve for 11Mohm resistor capacitance and Q by match Steve's Q measurements. Results were 0.4pF with Q=45. Xc = 1/(2*Pi*1.7e6*0.4e-12) = 234kohm Rp = 234k x 45 =

That is all true, but once you coil is built, the self capacitance will always be there, all you can do is build to minimize it. Don't you pretty much have calculate with indicated values when

*The real issue of Q with additional resistors is the self capacitance of the inductor.* If you look at the HP manual there is a nice graph showing the effect of self capacitance on indicated Q. It is

Here is the image I tried to insert between the dashes in the previous message. The attach image freaked out, returned a bunch of errors and posted the message without the image. Tom, wb6b

Fascinating. Spent about an hour going through the articles and especially the ads. Wow, TVs ranged from $99 kit ($1,200 in todays dollars) to some kind of small rear projection TV that would cost

-- Thanks, Mikek

Yep, I looked up the link and saw they hav0.140 resistor so, no need to do anything different, there is enough confusion! :-)

Hi Mike, Nothing magic about 7 resistors. I used it because it was easy to draw in Visio with resistors on 45 deg slants to make 8 in a circle. There is a type of SMT component, 1020(reversed),

On 11/16/22 12:07 PM, Steve Ratzlaff wrote: Attached is a SimSmith model of Steve's 11/16/22 measurement. Set DUT Q to match measurement without 11M resistor. Added 11M parallel resistor and adjusted

Yep, my thinking was backwards, skin effect would cause the value to rise. OK, I was blaming Cp before but with the wrong reasoning. Help me understand, I still believe we tune out the capacitance of

Hi Mikek, What caused Rp to fall ? Good question ! One would expect that the resistance would increase with frequency, as predicted by the skin effect. But this shows up on conductors or "low" value

https://www.amazon.com/BOJACK-Germanium-65Volt-Electronic-Silicon/dp/B07Q4J9WMX/ref=sr_1_1_sspa?keywords=1n34a+germanium+diode&qid=1668886994&sr=8-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1 Lester B

Where did you obtain the germanium crystal?

Oh, I just found a reference to skin affect in resistors, could that explain all if the change? -- Thanks, Mikek

I can understand why strays would cause a change of impedance with increasing frequency, but as I understand it, your graph shows Resistance changes with frequency. What is the cause of that change?

I got confus ed again, I thought we had a private conversation going, but I guess all can chip in now! Hi John, I like the 7 smd resistor idea, I went to bed thinking about how to make it work. I

SimSmith Injection Transformer Q-Meter model attached. Block L = Voltmeter with 100Mohm input impedance Block B = inductor DUT with added Parallel resistor. Block A = 50:1 Injection Transformer Using

Oops, SMT resistors in a circle directly around the binding post post can make a very low inductance 20 milliohm resistor, but a 2500:1 divider is probably not very useful. John KK6IL

I went with you your numbers, seven 0.140Ω resistors in parallel is 0.02Ω. Oh, I see, a 50Ω to 0.02 resistive divider is 2500 to 1 , not the 50 to 1 I said. So 1V into a 50Ω to 0.02Ω voltage