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Hello there! I absolutely LOVE the v0.8.4.5 (on NanoVNA-H) for its' speed and general feel. I wish that firmware would be used as THE golden standard for any further development. Thanks, DiSlord, for

Dear Cliffird, I guess an attempt to create a decent CM-choke for the 50kHz~300MHz span would be DIFFICULT, more so for a wider span. Are there any engineering instructions on the topic? Warm regards,

/g/nanovna-users/files/NanoVNA%20PC%20Software/NanoVNA-Saver/nvna-s-pve-rev-c.pdf Thanks for the LM20 test Nels. Just tested these instructions again with nanovna-saver-0.3.4 and

You need them solve one problem: NanoVNA use interpolation then change frequency range/points count, made measure from PC command. And need original calibration data from flash for calculations. Yes i

Also DiSlord, if the number of sweep points was reduced from 101 to I think 95 points it would allow each calibration save to fit into 4096 bytes of flash, which would free up 10kBytes of flash area

I was going to add the SD card menu to allow the user to save the config and all 5 calibrations to the SD card, and allow them to restore them back from the SD card, but currently too short on

ahhh good. Thank you DiSlord for the info, just updating now..

Excellent point, Dana. (Note: If you cannot read the formulas in my outlook created email text, you can find them within the word files attached.) Once you have obtained both complex common mode

LSI and LSE mode depend from Makefile flag One of reason not public this code (need support 2 version, and user errors), need add autodetect installed quartz, for this need rewrite part of ChibiOS

OK Igor, thank you for letting me know, I forgot about using the external RTC xtal (or not). I'll do two versions then, one that uses the external RTC xtal (LSE) and one that doesn't (HSE). It's

You took the words right out of my mouth :) Thank you!

Up till now there are guys that did not answer your question. I know about the noise on HF bands, I know about receiver specs, I know about receiving antennas. Please spare me. Here is an amp that

While this microwave capable device is cheap for the performance, for HF useful devices are going to be uber cheap in comparison, with transistors going for pennies, rather than dollars.

Post purpose: Practical usage of device on HF

Especially on the low bands a preamp is not useful unless you are using a beverage or small loop for RX. With normal antennas just the opposite, adding some attenuation, is often helpful. 73 -Jim NU0C

Not that I know off Sam. I would do for you it if I had a H4. Maybe sometime I'll get one but can't at the moment.

Yes I know David, was just an example for matching really, but it gets you close which you could then optimize for best N.F, it's starting point if nothing else.

Trouble is, these pre-amps have a LOT of gain once you get as low as 50MHz, mine has an attenuator on it because of that, and it's only stage of amplification in the entire receiver system, which is

Does your receiver need a pre-amp? If the atmospheric/background noise INCREASES when you connect your antenna, you don't need a pre-amp with that antenna. Be sure to turn up the RF and AF gain enough

That looks fantastic... will it also work down to 40m and 80m? if no, is there a similar preamp out there that will handle the lower bands?