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The second one is pretty much what I was thinking of. Apparently he is making the Gerbers available.

Hi Barry, I agree with Arie above. I wonder if you have seen the slides from my 4 hour presentation on the NanoVNA (some stuff is probably outdated now).

Howard and Rudi, I have gotten the SWR for the DIY 70watt HF Amp kit to work with a Hermes HL2. It took a 16ohm 5watt or higher resistor across the secondary of the input transformer. If you look

Hi John, Attached the screen print before it disappears. I am grateful for the assistance. Danie ZS1DBJ

Hi Barry, It's getting more beautiful every new version, two thumbs up. About the Smith Chart and losing the audience. If I explain the Smith Chart to my children (read: listeners) I start telling

EXAMPLE from DAYS PAST: In the TTL days of logic long past to newbies, it was common practice to place a black, CK05 (0.1 ?F) capacitor at each end of a row of logic chips. This was placed between

Hello Howard, Do you have this one bought? https://www.ebay.de/itm/70W-SSB-linear-HF-Power-Amplifier-For-YAESU-FT-817-KX3-DIY-Kits/272629674094?hash=item3f79feb06e:g:xvwAAOSwAANY73ML I could not make

* Nano VNA overview by K3EUI Barry * Each time I give a "talk" on the Nano VNA I learn something new. I've given five talks now, and from the questions from listeners, I know where the

I use my nanoVNA to test the input swr. I found that the 70 watt kit on eBay has a high SWR at the input on some bands. I am in the process of optimizing that now.

Clyde Spencer wrote: The chart says the frequency it is measured at. Not how much inductance varies with measuring frequency. I have carefully measured normal HF range inductors with a dip oscillator

CAPACITANCE AND INDUCTANCE ARE SPECIFIED AT A GIVEN FREQUENCY. See the example. [image: image.png] *Clyde K. Spencer* wrote:

Adding to my reply: The reactance of 470nH at 50kHz is barely 0.15?. You cannot expect the NanoVNA to measure that accurately. You need at least 5MHz or so to bring the reactance up into a range

Ed, The value marked on a component is supposed to be valid at a very low frequency. As soon as the frequency goes up, parasitic effects become increasingly important, so the actual value of the part

To over simplify a bit, the nanovna is a transmitter. It also has a sensitive meter circuit inside, which would probably be destroyed by power from an external transmitter such as your kit. A poor,

The short answer is NO you still need a dummy load or an attenuator that can handle the power from the transmitter. Then VNAs are not really designed to do spectral analysis of transmitter output.

This might be a dumb question, but I wanted to know if you can use a nanoVNA to test a transmitter built from a PCB kit (like instead of a dummy load). I realize VNAs are usually used for antenna

Hello Ed, Curious, if you go to item13 on your card, take that reading at 50 kHz and SUBTRACT the L value from the reading at 50 kHz done at item8... Do you get 470 nH? A reading of 700 nH at 50 kHz

HI, I use a different approach when I need to know the exact value of inductance or capacitance, I build up a simple jig on a PCB mount connector with a series 50 ohm chip resistor then put the

Not exactly like this, but see: https://www.aliexpress.com/item/4001204244685.html and

There is always some parasitic C around, which usually "reduces" (or cancels) some of the inductance - sort of the opposite of what you're seeing - but in any case, the amount of cancellation you get