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Generating 20 mV drive level with a 50:1 divider only requires 1V RMS, 2.828 P-P, which I would expect most signal generators would do, or not hard for a DIY generator. Higher drive levels for very

On Fri, 18 Nov 2022, Chuck Moore via groups.io wrote: Iodide electrolyte is very good for this. A bit expensive because of high potassium iodide price but very stable unlike cheaper cyanide bath and

Generally, mil-spec silver plating starts at 0.0005" thickness, however a number of shops now plate upwards of 0.015" if ordered. If you do silver plate you want to be sure to use silver's

I have a few 6" high Q coils, get within 18" and you can watch the Q drop on the Q meter. Mikek

Cool-Amp is easier than electroplating ... but if you're up for electroplating, it's not too difficult and you can just leave the copper coil in the "soup" until you think the plating is thick enough.

You have to ask the question, how the thickness of that plating compares the the skin thickness. At 1 MHz, skin thickness is 0.0025". I don't have any guess for the thickness of that plating, but I

Oh, he does say 0.2Ω--- Now I don't like it :-)? I've going through the Boonton 260A manual and have the 0.02Ω etched in my mind. I see one problem with the resistive 50 to 1 voltage divider, it is

You may want to try Cool-Amp, but it's awfully expensive. 73 Jim N6OTQ

Definitely pure soft silver from my bullion supplier.? They do recycled and Sterling, but it's no use as you rightly say. Neil

If you use silver wire, make sure it is pure silver. Sterling Silver has an IACS conductivity of 96% - which means that pure anealed copper is actually ~4% better.

The author's approach is not to cancel the inductance of the 0.2 Ohm (not 0.02) resistor but that of the 5 CM (2 inches) of connecting lead. Multiple surface mount resistors mounting in a ring around

I use solid silver wire and polish it before winding. It's relatively low cost and much less trouble than plating. -- Neil G4DBN https://youtube.com/MachiningandMicrowaves

What I discovered over the years was a lot of people already walked the path I was currently following. No where did this become more self evident than the construction of? helical wound inductors.

Hi Jacques, I hope to get some closure on this, I have been a week on and off trying to understand the measurement. The question is what causes the R to fall? It is my contention that on the Q meter

Please take note that high value resistors have their resistive part decreasing with increasing frequency. The attached file shows the test that I did on a 1 Mohm 1/4W leaded resistor, from? 300 KHz

Hi: When I was spending a lot of time winding high Q coils and testing them on the Boontoon 160 it was clear than anything closer than maybe a few coil diameters would effect the readings.? So this

Here's an interesting approach to countering the inductance of the 0.02Ω source resistor. The author says it's good from 100kHz to 40MHz. He doesn't provide a lot of build details. I wonder if it

Yes, I'm aware of that, but not much happens until you get over 500MHz and even 1 GHz, I'm working at under 2 MHz. -- Thanks, Mikek

Yaego has docs which show how the impedance diverges from resistance in various body styles. -- K1FZY (WA4TPW) SK 9/29/37-4/13/15

I did six more measurements of a 10MΩ smd resistors this morning, all fell between 7.2MΩ and 8.1MΩ. -- Thanks, Mikek