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In the write-up, the last 'subject' was professionally done. Notice it consists of 16 turns of AWG #14 solid copper wire wound in a bifilar manner. This one measured the best and is the size of the

Attached are the measured data sets for the CM chokes I illustrated in the previous email plus a couple of others Dave - W?LEV wrote:

For the doublet which consists of two roughly equal lengths of wire each side of the center insulator, just wind yourself a common mode choke. It will serve very well as a balun as it will discourage

Thanks for the detailed explanation of the graphs I could certainly follow it on the graphs. I have 2 of the T130-2 cores but the only mag wire i have measures 1.90mm across which is way too heavy to

No.....NO.....N O.....!! Something is wrong, here. Look at just the Smith Chart! Open shows lots of loss. Short shows very high Z. 50-ohm termination shows high Z and totally inductive. All show

so if the balun is good how can the wires themselves be bad? I would have expected this ant to be usable across the band windcamp advertised it to work at 5-50Mhz but it seems in most cases my Kenwood

From the plot with 50 Ohm resistor you can see, that the balun is good (VSWR < 1.5) from 3 MHz to 30 MHz. The other plots are unimportant. But remember that an antenna with bad VSWR will also give

Thanks Larry, yes I thought to remember that and searched the forum using "H4 LCD screen" etc. but no luck. Will try again using his name for the search. Best regards, Jos Op 5-11-2020 om 18:35

I decided to test the Balun itself maybe someone can help me read these plots. I have one plot with the ant lead of balun open, shorted and with 2 100ohm resistors in parallel that read 49.9 ohms on

Hi Ernest, No problem abt the name and thanks for the info. Regards, Jos Op 5-11-2020 om 17:40 schreef ERNEST AEC-RADIO:

I sill have the copy of MININEC that I had to sign for from the Naval OceansResearch Lab 33 years ago.?? Don't do a lot of simulation.? I have an antenna rangethat goes up to 30 GHz.?? Currently

Yes, quite a number of antennas modeled and built using 4NEC2 by myself!! And,..... I have the professional equipment to do proper testing including an HP 8753C VNA with associated S-Parameter test

Pretty models, but have any been tested? So far we have two families of antennas that HFSS cannot model. Oh, you get nice fancy diagrams and plots, but no where near thetest results.???? There are

4NEC2 can model a helix quite well. I've designed and constructed several using that modeling application: https://www.qsl.net/4nec2/ Dave - W?LEV [email protected]> wrote: -- *Dave - W?LEV* *Just

Thank you Dave, Got Your point. I removed the antenna from the roof and brought to the shack and measurements withouth the cable were really close to the real SWR as seen from TX. Next step would be

Hugen had previously posted the part number in the forum. I think if you search his posts and "LCD" from Nov 2019 through to around Feb 2020, you'll find the post.

That could well be the case, when Sandpiper were manufacturing those antennas back in the day, their test equipment was fairly limited. I believe they are better equipped now. -- Regards, Martin -

Jos: I apologize for not looking at your name... I fat fingered my keyboard....again! [email protected]> wrote:

Joe: Because the LCD is adhered to the board, you will need to pry it loose from its adhesive bond. There is normally a numbering system imprinted on the display, which denotes manufacturer name,

Hi all, I have to replace the LCD screen of my NanoVNA-H4, please what is the type number and/or where to buy ? Thanks in advance, Jos