I was working quite a while on my GPSDO project. This post is still work in progress and I will provide some updates from time to time 😉
When I wanted to build a diplexer, I read that this can be done by using a highpass anda lowpass filter. But what if someone wants to make a multiplexer, or if one wants to use bandpass filters?
My next project is to build a GPS disciplined oscillator. I have bought a NEO6M GPS module (GY-GPS6MV2) which uses an active antenna. However, there are several drawbacks which I want to fix first.
My HP 8753C network analyser has options 010 and 006 installed, with 006 being the 6 GHz operation and 010 being time domain analysis. However, there is also option 002, which is called harmonic analysis.
UPDATE: I made a firmware dump & updated to the latest version!
I got a ‘new’ spectrum analyzer, which is a HP 8568B (100 Hz – 1.5 GHz). Unfortunately, it has some problems with the CRT, as well as some noisy traces.
With the lab power supply, the YTO worked fine, so I did some further investigations on the 8341A’s YO loop…
UPDATE: power flatness test!
Today, I decided to dismantle the YO loop of my HP 8341A to further search for the problem.
So, the HP 8341A which I recently got has several problems. Besides a bad YTO, it also has a burnt relay on the A62 motherboard. When fixing the generator, I decided to start with the easy things….
My employer wanted to throw away a HP 8341A signal generator. This is a 10 MHz to 20 GHz sweep generator! Of course I rescued that unit from trash….
Here I show how I designed a coaxial cavity bandpass filter. The method of Dishal is employed, using the k and q values. This was part of my Master’s Thesis, but here it is explained in more detail.