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Are you reading this on the web interface, or in your mailer? #WeNeedMoreInformation 73, Willie N1JBJ

Only me provide H/H4 firmware, so i number it as i want (increase number every main update) V2/V2Plus - difficult ask, main vendor https://nanorfe.com/nanovna-versions.html In all cases if my firmware

The Teflon wire came from Surplus Sales of Nebraska. It isn't the least expensive (cheap), but it's well worth the investment. Here is the reference:

Ok, for NanoVNA V2 SD card support need: Use RTC for auto file name, RTC on default V2 used in bootloader, so have limits (restart on power on, slow tick), better update bootloader, but at this moment

Dave, Someone taught me a trick years ago, wrap the cores with Scotch fiberglass tape. It pads the cores. It a lot more difficult to scratch the wire coating. I used 12 turns of #14 bifilar for my

Back in February during my 'mad' exercise of winding bifilar common mode chokes (CMCs) I found it rather easy to obtain in excess of 3KΩ impedance against CM energy. These were all measured using the

OK, I see last thread activity as FIRST in " Messages " . How about presenting the last , current entry first LIFO - last in first out Is that an option ? 73 AA7EJ

This is a question of techie curiosity , so take it as that. Name one instance where one would want to calibrate anything in such wide range ? While testing what ? Would it be more practical to

or see: http://k9yc.com/2018Cookbook.pdf 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL Technical Specialist, RFI ARRL Asst. Director, NW Division, Technical Resources

Type 61 is the wrong type for 75/80 meters. 1500 ohms (higher is better) is the choking impedance, so it should be a high value. http://www.karinya.net/g3txq/chokes/ Max

This is a picture of a CMC using 240-43 core and RG8X.. I measured the CMC reject from 3 MHz to 30 MHz. I was greater than 30db across the entire range. I also tested this CMC under full 1000 watts

Maynard, thank for drawing attention to the difference in propagation velocity. I meant to address that. The propagation velocity on the outer coax shield is independent of the velocity factor of the

Great models Dave! Question: How practical is it to make a 1500 ohm choke for 75 meters? Back of the envelope calcs say that would be abut 8 turns on an FT-240-61 core which would be impossible with

Hi Mike, You need to be careful with adding TF sockets as some have additional pins, so the edge pin number may differ. Some also have the TF card inserted upside-down which reverses the edge pin

Hi I have been following this thread. I am a bit confused and very old so …. I have the VNA-H SAA-2N. Is there a concise instruction set that shows the EXACT steps to install this upgrade. I really

Digikey has the extraction tool: their part number is H9159-ND

An excellent description, Dave. One thing to note is that the velocity of propagation of the transmission line formed by the two "innermost conductors" (the outer surface of the inner conductor and

Thanks Dave! 73, and thanks, Dave (NK7Z) https://www.nk7z.net ARRL Volunteer Examiner ARRL Technical Specialist, RFI ARRL Asst. Director, NW Division, Technical Resources

An antenna with a feedpoint impedance that matches the characteristic impedance of the coaxial transmission line it's connected to may indeed have common-mode current on the shield. The match is no

------------------------------------------------------------------------ *From:* DiSlord [mailto:dislordlive@...] *Sent:* Sunday, 25 July 2021, 8:56 pm *Subject:* [nanovna-users] NanoVNA H / H4