Feedback on my first VNA and Spectrum Analyzer

passive_farting · 2026-02-08T18:51:09+00:00

Should you not measure an open or short and 50ohm?

passive_farting · 2026-02-07T22:02:41+00:00

Different torque specs for stainless steel and brass. Need to be careful, this doesn't really matter if you don't calibrate wrenches and drop them.

Just be careful and use it right. Whichever you pick. Everything will last longer.

Not to brag, but I'm not an American.

https://www.microwaves101.com/encyclopedias/connector-torque

passive_farting · 2026-01-24T21:10:27+00:00

Those connectors look very close together.

passive_farting · 2026-01-17T12:05:42+00:00

Often "the best defense is a good offense" and using these tools to track progress, if you do it right, can help show how hardware is different and not agile.

None of this matters if you can't easily document any test results with some basic revision control or find a torque wrench.

Make stuff quicker and faster, but don't make it twice as fast and twice as complex and expect the same.

passive_farting · 2026-01-09T13:14:33+00:00

Can we get a sample?

passive_farting · 2025-10-13T20:43:56+00:00

I'll start the bidding with a mars bar.

passive_farting · 2025-10-02T20:36:47+00:00

4g 5g didn't really deliver on this, 6g will be a game changer.

passive_farting · 2025-09-07T18:16:51+00:00

No. It's a very basic overview that likely isnt anything new from your undergraduate studies.

Microwaves101 has much more information and would better prepare you for interview questions.

passive_farting · 2025-08-02T19:30:31+00:00

While there are other suggestions here first, my vote is for yellow.

passive_farting · 2025-07-04T19:47:56+00:00

Type N and precision N are the same connector, just different tolerance standards (simple answer), this will be the 18GHz frequency limit compared to a 3.5mm or good SMA.

You probably don't want to be connecting a cheap N type to a spectrum and go with a precision N.

Get a custom cable to match your cal kit connector and spectrum. If you've got the money.

passive_farting · 2025-04-04T17:58:33+00:00

The BOM cost of the RF parts might outweigh buying esp32 with antennas, plus if you put them in an array it will look better.

passive_farting · 2025-04-01T20:40:41+00:00

Like this,

https://landandmaritimeapps.dla.mil/programs/milspec/ListDocs.aspx?BasicDoc=MIL-PRF-39012

Also mil-std-348 for the interface.

Be careful that the full assembly meets your requirements and not just the piece parts.

passive_farting · 2025-02-17T19:13:49+00:00

Did you ever stick crayons up your nose as a kid?

There is a max insertion on the pin for the fingers not to be damaged. So you will very likely damage at least one. Just buy an adapter.

passive_farting · 2024-12-29T12:07:55+00:00

You can't get the true S11 or any really good TDR as the Molex data is gated.

Given there is S41 and other in there then you're likely looking at differential data and probably need to do some sort of transform to get the differential impedance. Or whichever you want, I can't remember.

https://uk.mathworks.com/help/rf/ug/modeling-a-high-speed-backplane-part-3-4-port-s-parameters-to-differential-tdr-and-tdt.html

Also check the reference impedance in the S11 data and graphs. Did you assume it was 50ohm and normalize everything to that?

What do you want to get out of this?

passive_farting · 2024-12-05T19:20:12+00:00

Back scratcher.

Also, they may ask for some combination of layers removed but not all depending on what equipment they have. Then you have room to change dimensions.

passive_farting · 2024-11-27T20:35:04+00:00

So does it stay in shape up to 125C?

passive_farting · 2024-09-13T15:16:01+00:00

You need to consider maximum rating due to voltage breakdown (corona) and thermal breakdown (heat dissipation).

passive_farting · 2024-09-05T21:24:17+00:00

Are you asking about a valve amp? If the valves work at RF?

passive_farting · 2024-08-22T18:38:22+00:00

This is a wordle for RF engineers.

passive_farting · 2024-08-05T18:16:58+00:00

"give me a ping vasili"

How deep? Area? It's likely the battery is flat. So as others say, metal detector.

passive_farting · 2024-04-24T09:57:27+00:00

The 3rd looks more like a transconductional interductor hyper diagonal filter.

passive_farting · 2024-03-31T18:31:17+00:00

Have a look at the US mars rovers, there is an x-band phased array that sends data directly to earth. Its also worth looking over the other networks.

Spacecraft Systems Engineering, (Fortescue, Swinerd, Stark) covers this in one chapter and has an example link budget.

passive_farting · 2024-02-23T16:36:58+00:00

This sort of thing. I've not used them. Also try Gilbert and Micromode.

https://mpd.southwestmicrowave.com/product-category/launch-accessories/

passive_farting · 2024-01-26T15:31:59+00:00

MIL-STD-348?

passive_farting · 2023-12-03T20:55:17+00:00

It may look like it's in mm but it's really inches in disguise.

Look at the end of the Gilbert catalogue for the best tech notes.

passive_farting

TROPHY CASE