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No, 12k is IF used in measure. So not possible measure on this frequency or it harmonics PS in H4 possible change IF in config-expert settings menu

Just buy more than 1 set of adapters - there's plenty of room in the divider bins. 8-) I've gotten too old and grumpy to use the coffee-can approach - when I dump it out I have to root around to find

Problem with this kit is that there is only one of each! Most times, I need several of several kinds. ADVICE: An old sage at VHF/UHF gave me some excellent advice 50 years ago. Get yourself a 4 or

I use Pasternack at work, where it makes sense to pay $40 for an N-to-LMR600 crimp connector. For my hobby use that's impractical. I can assemble a whole bin of adapters (and I did) for less than a

The subject line is longer than the message. .. .. ... .... ..... Dave - W?LEV -- Dave - W?LEV

Where come from the 12 kHz noise? Possible to filter?

Thanks, I did some more checks: power supplies on the pins of the various devices were ok, clocks were also present (except the 32 kHz, I guess it's used maybe only for the RTC during power down?) but

If DFU works the STM32 microcontroller is working (VDD and clock). Check also the internal supply voltages +5V (U3 / pin 1) and AVDD (U10 / pin 5) - expect 3.3 V. Check the output of the 26 MHz TCXO

Wow I'm impressed, what a website everything you wanted to know about testing crystals. Thank you Lex.

I have tested and sorted quite a few crystals using a specialy designd adapter for the NanoVNA. See: https://www.ph2lb.nl/blog/index.php?page=xtal-adapter-for-nanovna

What the VNA will not do is tell if a given crystal will oscillate, cleanly and on frequency, in a particular circuit, which is what the OP wants. 73, Don N2VGU

Hi Tom; You might try reflashing the firmware and also the bootloader. Both may have been corrupted when the battery died, and it sounds like the bootloader MB ay still be. -- 73 Gary, N3GO

The basic go no go test as described is fine. However if you want to accurately determine the crystal parameters you will need more work. For HF crystals a good test jig to avoid strays is useful.

Rob, Thanks for the info. I've got a few crystals laying around and I'm basically just looking for a go/no-go on the crystal as it appears dead in circuit. I'll watch the video in the morning, too

Justin, Either should work for just seeing if the crystal has a resonance near the expected frequency. I've just used channel 0 for S11 measurements, with the coax shield to one side of the crystal

Thanks, Rob. Do I need to use both channels or just the "primary?" 73, Justin B. KI5GKD

I use mine often to check crystals when I suspect they may be bad. I have some SMA to alligator clip cables which make it easy. You can over the expected frequency range, and you should see a S11

I'm working on my Heathkit HR-1680 receiver and I have a crystal that I suspect is bad. Can a NANO VNA be used to test a crystal? If so, how? Thanks and 73, Justin B. KI5GKD

Hello, I have a NanoVNA-H4, since 1 year, that worked fine until yesterday: I left it running overnight and this morning I found it with the screen frozen and unresponsive. Cycling power it now shows

You can measure them as you would any other lumped component. Typically you’ll wind up with a Z like 2 + 300k j, which is hard to measure. As to whether the measured Z is meaningful is a whole other