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Antenna 70 cm longyagis


The elements have 10 mm, 8 mm or 6 mm diameter, because this is very uncritical and you get the expected datas! For the tuning let the radiator 2mm longer and cut for best SWR at 432 MHz
post 16 Jun 2024
Antenna 70 cm longyagis

Antenna for UHF VHF Links

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Antenna Half-Square
If you need a vertically polarized bi-directional 2-meter antenna with deep side nulls for direction finding or nulling out adjacent channel interference, try the half-square

Antenna HB9
La hb9 fa parte della famiglia delle antenne logaritmiche. Piu' precisamente e' una log periodica a soli 2 elementi, quindi un'antenna con tutti gli elementi attivi e non come la Yagi: un elemento attivo e tutti gli altri passivi

Antenna quad 144 MHz da appartamento
ho voluto provare a farne una versione da appartamento leggermente modificata a 6 elementi con guadagno teorico di 13 Db

Antenna VHF Topfkreis
Rispetto alla sperrtopf l'alimentazione viene portata all'esterno tramite un forellino dal quale fuoriesce un filo di rame collegato ad un bocchettone UHF

Antenne double quad 430/440Mhz
After simulation of the antenna on 435Mhz, the results are as follows and in reality the bandwidth is very good. 1.5: 1 between 430 / 440Mhz


23cm Yagi Antenna building

23cm Yagi Antenna building Finished antenna at 1275 MHz SWR under 1:1.5 at resonant frequency

50 MHz preamp Gain 26dB with the BFG135

50 MHz preamp Gain 26dB with the BFG135 Preamps for 144 and 430 MHz, for 50 MHz, the BFG135a is a cheap transistor and in my view rather strong. It is not easily damaged by static discharge or RF power. FG connection

30 Volt Computer Power Supply Stack

30 Volt Computer Power Supply Stack A bonus was that i discovered that these did not need a standby load connected to the supply to keep them running just apply mains power and close the Start lead to ground