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With my newly wound transformers, 1 to 8 ratio, I now get the following results (see images) when they are placed back to back. As shown in the S21 plot I am getting a loss of 3 to 6dB The matching on

Herb, I've been waiting for the V2 since I read the outlined specification in fall. My main interests are in 20m, 2m, 70cm bands and I'd like to be able to probe 1.575GHz as well, hence my wait for a

I followed the discussion about making BALUNs and the reference to "Beverage Antenna" which was new to me. With the Google I found the Wikipedia page on it and then the US patent application which

I noted the 73 material good LF material but not so good at over 10 mhz. When going for odd ratios adding turns sometimes works better. Or if minor loss is tolerable use a lower ratio and load down to

The reason I removed a bit of a turn (and then called it half a turn) was this seemed to make a better match. Though in reply #11793 I accidentally called it 'one turn' when I meant 'half a turn',

On Wed, Mar 18, 2020 at 10:32 AM, Roger Need wrote: It is my understanding that after you do a Clearconfig 1234 you must turn off the power and after turning the power on do a touch calibration and

I was using magnet wire to wind the transformers but have rewound them this afternoon using insulated wire. They now look like the transformer shown in the W8JI link you sent. They are wound 1 to 8

On Wed, Mar 18, 2020 at 10:33 AM, TT7 wrote: Sadly, they are not shipping to the Czech Republic yet. =================================================== Tomas, Probably just as well. There have not

Sadly, they are not shipping to the Czech Republic yet. In an email response, the seller said they were looking into adding other shipping methods, but no time frame was given. Tomas

It is my understanding that after you do a Clearconfig 1234 you must turn off the power and after turning the power on do a touch calibration and then a calibration with a save to Channel 0. Maybe Heb

First 1 turn is always though both hole there is no .5 turn. Also if the inductance of the winding is not high enough you get a low frequency cutoff. Changing the ferrite to higher mu (43 to 73) will

https://www.tindie.com/products/hcxqsgroup/nanovna-v2/

Hello, If one uses *nanovnasaver*, what do you think it will be the best firmware? I am fortunate to have a small PC at my desk to use with the VNA. *73 de Luís, CT2FZI* http://www.ct2fzi.net

clearconfig 1234 did not seem to help To calibrate I: Connect open to CH0, OPEN Connect short to CH0, SHORT Connect 50 ohms load to CH0, LOAD Remove 50 ohms load from CH0 and connect to CH1, ISOLN

In fact this issue is not a big deal to fix it by adding washer. However, it would be frustrated when happens. I did encounter the issue with my 2.8 inch H version so that I simply go back without the

Kerr, I don't how you are winding or measuring these transformers but something is definitely not right. The coefficient of coupling K is very close to 1 with binocular cores and the core losses are

I have never heard of anyone counting a pass through one hole of a binocular core as a full turn. Fair-rite states: "The 61 and 67 material multi-hole beads are tested for AL value. The test frequency

So, the good match is likely mostly due to loss. Of course, since you have two transformers in the measurement, the loss through one is half the S21 values. Still, most of the good match is due to

Below are S11 plots of R + jX and |Z|, these look quite similar to yours I think - the Y-axis scales on mine are zoomed in a bit (I did try to set them from 75 to -75 on the Y-axis to match your scale

I have just removed the 50 ohm resistor off the second transformer and attached CH1 of the NanoVNA instead. The attached image is the S21 plot of the sweep from 1 to 30MHz. At 7.15MHz the gain shows