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Here is an article about crystal filter analysis by nanoVNA: https://ttrf.tk/posts/2017-01-15-measure-crystal-filter-with-nanovna/

Thank you Alan W4AMV, Finnally I have my nanoVNA correctly calibrated. I am happy now with the measurements! Cheers and 73 Luís, CT2FZI

There is a filter spurious on the high side of the skirt. This shows up as a spike on the VNA display. There is none on the low side skirt, despite what appears to be a spurious on the VNA display. I

Never one to back away from a puzzle, the resistive pi network for crystal testing reverse-engineers to a 50 to 12.5 ohm matching pad with just under 15 dB loss (14.774).? Probably trying to "match"

It was tested with a small ground plane. Tried other configurations too, but with only very small changes. This antenna was bought on eBay for US$0.99 with free shipping. So it was probably a poor

Does it require a ground plane? I would put an SMA connector centered on a plate of PC clad card. Then feed the cable thru back to the VNA. ________________________________ Sent: Thursday, July 11,

Decided to test this SRH805S wide band antenna. They claim it covers 144/430/1200 MHz. While the nano doesn't cover 1200 MHz, it does handle the lower two bands. Clearly there is a problem as 144 MHz

"Have searched the net, but did not find a copy of the QEX 2017/05. Do you know any source for this reference?" Try searching for, or emailing, the author. Often they will provide a copy to you as a

This 500 Hz bandwidth filter is problematic. Upon further measurements with another instrument there are issues. I will find another baseline network and report findings

QEX is a magazine published by the ARRL for communications experimenters. The articles and papers in it are much more technically-oriented than most of what is in the QST ARRL magazine. One must be an

In crystal factories crystals are measured in a 50Ohm system with a pi-network on both sides as per enclosed picture. Don't know if the resistance values are readable in the compressed picture so here

Have searched the net, but did not find a copy of the QEX 2017/05. Do you know any source for this reference?

I can pull mine apart and see if I can come up with something. I agree, the "external" parts need dome protection

Some people don't have the "ability" to modify that box. This way, if you just wanted to add a (or bigger) battery, it is only 4 screws and double sided tape (which I could probably throw

There is some value added packaging if it can be done at a reasonable cost. The slide switch and the rotary wheel switch are subject to failure or breakage. Especially when used in the field. The LCD

I think it depends on the battery. I'm looking for "surplus" batteries to keep the cost down. I had mine open, and never looked to see the mAh rating on the battery. I figure under 1000mAh should be

Folks, Instead of reinventing the wheel to design a case, have a look at the 1553BBK series Hammond housing. It's approx $12 CAD. It looks like a small amount of internal trimming might be needed but

I am still interested, depending on price. Norman Eric Haskell, KC4YOE 3709 Oakbriar Lane Colleyville, TX 76034 USA ________________________________ Sent: Thursday, July 11, 2019 7:25 AM To:

If anyone is interested, I'll find a battery and make up a package with screws and figure out a price. I can make the backs in black or white (or other colors) Frank

In this video, Alan also correctly designates the IF BW as Resolution BW in his notes.