@n8dmt I don’t have a scope or sig gen. But I used my SI5351-based VFO to test gain with the TinySA and I tested S11 with the NanoVNA. I’m not sure how to test S22 because the power out is higher than the NanoVNA can take and if I pad it that will obviously mess up the measurement.

I tested gain through a 23dB pad I made so as not to run over the TinySA. Bandwidth I will try to test with the VFO/TinySA.

None of it is exactly what I got from Qucs-S but I expected that! #HamRadio #AmateurRadio

Well the amplifier I soldered up last weekend that didn’t work has been fixed and seems to do what it’s supposed to. The soldering job is not going to win any awards for sure. But with the amount of rework I did, and my surface mount experience level, I think this is fine. It’s hard to tell here but the whole circuit (not the board) is smaller than the first two joints on my little finger.

This is my 2m band #HamRadio antenna amp I designed. It's quite different from my experiments a week ago. This one is a cascode layout with two BFR193s, a nearly perfect 50 ohm match on both sides across the whole band, and just shy of 18 dB of gain. Tuned with S-Params.

In theory! Now to build it and see how close I can get.

If you are looking at learning RF circuit design, take it from me: skip LTSpice and download Qucs-S. This is a really nice piece of software. #AmateurRadio

Soldered up the audio amplifier from the Soldersmoke Direct Conversion Receiver. Built it in my old construction style but next parts will use Manhattan style, which looks even easier. Sadly could not test and just went ahead and built it in hopes that it works because I can’t find my speaker. Ordered another one and will test this week. It has a lot of junk box parts (hence those huge caps and the parallel caps, series resistors). Fun project. Hope it works 😀 #HamRadio #AmateurRadio

I designed a small signal 2m RF amplifier around the transistors that I bought. I didn't want to reuse someone else's entire circuit because I wanted to understand how it works. I maybe 10% understand it now (this is a complex topic!), but that is enough to make something that looks like it should work. Simulated in LTSpice, but I will attempt to build.

Built around the BFR193 which is a really low noise transistor and is like €0.16/ea. #HamRadio #AmateurRadio

Messing around with making inductors for a 2m band pass filter and measuring them with the NanoVNA. I made an OK-ish fixture with some RG-316, SMA connector, and alligator clips, and calibrated it with the fixture attached. Getting pretty close to the 100nH I need for these! #HamRadio #AmateurRadio

Beginnings of an (I hope) SSB direct conversion receiver for the 2M band. This is just the VFO. And I’m very much learning here.

It uses an SI5351 with two signals 90 degrees out of phase. Controlled by a Pi Pico. While the code works, I’ll need to make it more efficient to handle the other duties that I plan for the Pico. This is my first Pico project, too. I’m using the Arduino IDE. #HamRadio #AmateurRadio

Finally got my new (to me) Kenwood TK-760H ex-commercial rig on the air today! Had a chat with a guy on the local 2m repeater who confirmed good audio from the replacement mic I bought. Radio is capable of 45W but I’m running 25W into the local repeater through my copper tape/duct tape J-pole. Very happy with this setup! #HamRadio #AmateurRadio

I built a duct tape/copper tape 2m band j-pole antenna today that seems to work great. I managed a 1.2-1.4 SWR across the whole band. Attached photo shows it hanging in the corner of my office above my desk. I used my NanoVNA to find the feed points. Attachment of coax is via neodymium magnets with bolts through them. Ideas all from various YouTube channels. Fun! #HamRadio #AmateurRadio