DL4ZAO has further developed and modified the circuit of the Mini-Whip antenna and published a number of variants. Here you can find the website of DL4ZAO: dl4zao.de
DL4ZAO BlueWhip MegaWhip
I have rebuilt the MegaWhip from DL4ZAO. The reception is much less sensitive to interference compared to the Mini-Whip from pa0rdt. Link to the building instruction: https://www.dl4zao.de/_downloads/Megawhip.pdf
Features of the BlueWhip MegaWhip
- It is an active receiving antenna that cannot transmit
- The antenna is very broadband and you can easily overlook several mHz with the SDR
- By jumper you can add a FM band stop
DL4ZAO BiasTee Basic
I have also rebuilt the BiasTee. On the same website you can find a building instruction for a BiasTee. Link to the building instruction: https://www.dl4zao.de/_downloads/Bias-Tee-Basic_100.pdf