Broadband amplifier from 50 to 450 MHz
For my newly build 50-70 MHz amplifier I needed a suitable driver. I needed about 5W drive. I started with a CATV module, the BGY888. […]
100 – 1000 MHz
Coaxrelay homemade out of cheap relays
The need for coaxrelays for the new 50-70 MHz amplifier led to this design. I had very good experiences with the Fujitsu relay which datasheet […]
AD8307 Frequency compensated
The AD8307 is a nice logarithmic amplifier with a lot of uses for amateur radio. My SWR Power meter is build around it. (LINK) The […]
144 MHz Bandpass filter revisited
144 MHz Bandpass filter revisited The 144 bandpass filter as shown on my website (here) has been a very popular article. It was the most […]
Wilkinson divider for 145 MHz
For operation on 2320MHz I needed a receive power splitter for my IF 144 MHz. It had to cover the 100-150 MHz range. The first […]
Using the specan as a dipmeter
Using the spectrum analyser as a dipmeter For a long time I never had the need to have a dipmeter for HF and VHF. This […]
PCB low pass filters
In a discussion I had with Peter, SM2CEW and Graham, F5VHX, the idea grew to make simple low pass filters. Simple but suitable for fairly […]
2 x GS35 PA for 144 MHz
Here follows a photo description of a 2 x GS35 PA for 144 MHz. Beware this is not a fully tested design! There are no […]
144 MHz Bandpass filter
A 2 stage 2M bandpass filter using helical s. Note there is a new article about this filter with more information click HERE On my […]
Preamplifier with a MGF1801 for 144 MHz
A modification / combination of the DJ9BV & I5TDJ 144 MHz preamp designs The original I5TDJ design used a rather long coaxial input design. This […]