An interesting question made me think about whether it was possible to use lumped element quarter-wave transformers for a lumped element Wilkinson splitter.
Category Archives: RF stuff
My new GPSDO
I have not posted for a long time! Not only because I was too busy in the meantime, but also because I was working on a quite involved project: a new GPSDO!
Continue reading My new GPSDO
Lumped element quarterwave transformers
Everybody knows that a matching network can be built using a quarterwave transformer. E.g. if a load of impedance \(Z_L\) shall be matched to a source having impedance \(Z_S\), this can be accomplished by using a transmission line with an electrical length of 90 degrees and characteristic impedance \(Z_0 = \sqrt{Z_S\,Z_L}\). However, is this also possible using lumped elements?
A waveguide bandpass filter
See here how I made a waveguide bandpass filter for 33 GHz.
A homemade Ka band waveguide directional coupler
After I decided to make a waveguide coupler to see what results I may achieve, I have disassembled one and looked at its construction. Then I made my own coupler.
Continue reading A homemade Ka band waveguide directional coupler
VNA calibration
My old HP 3577A box does not allow for proper full 2-port calibration. So I investigated a bit in this field.
My new HP 8970B noise figure meter
I always wanted a HP 8970B noise figure meter to measure the noise figure of some amplifiers etc. However, these usually go for stiff prices, but recently I found an unit on eBay which was quite cheap.
GPSDO Testing
I tested my GPSDO by comparing it with my Oscilloquartz STAR4.
Design of a K-band waveguide directional coupler
As I said, after I made my own waveguide termination, I wanted to make a directional coupler in waveguide. Here is my progress.
Continue reading Design of a K-band waveguide directional coupler
A homemade K band waveguide termination
I want to do a few experiments with waveguides, this time I try to make a termination. Later I will try to make a directional coupler, so with the aid of the termination I can calibrate the directional coupler and do some measurements at higher frequencies.