Yet more excellent project offerings from the workbench of Alex M0TOT, and this one's a cracker.
I'm very grateful to Alex for supplying me with his project documentation. If anyone else has anything to contribute in terms of self-constructed goodies, then please do get in touch.
This is what Alex has to say about this really interesting active antenna:
"This is an unusual project; it may not be everybody’s ‘cup of tea’. Essentially it is an antenna-amplifier for receiving only, for the HF and VHF/UHF bands.
There is provision for connecting a telescopic whip for AM/FM, long wire, UHF and dipole. I believe the original designer, Tony Van Roon-Werten VA3AVR is now a Silent Key. The transistors can be found on the Internet.
I have a few spare boards, if anybody is interested in assembling this unit.
In order to check whether the item worked alright across the bands, I connected the Active Antenna output to my radio and attached a frequency generator to the antenna input in place of an outside aerial. Shown attached is a screen capture of the response of a 50 MHz signal on the radio. Other bands responded in a similar fashion.