Building a preamp for the VHF waveband (approximately 100 MHz) is simply not a straightforward issue.
This VHF preamp circuit, on the other hand, is not at all hard to work with and is quite affordable.
It has the main advantage of a reasonably large bandwidth (2 MHz) and good noise figure (2.5 dB).
The VHF preamp circuit includes a huge dynamic range and a gain of 20 dB at a frequency of 144 MHz.
L1 and L2 are usually air-cored coils having an internal diameter of 6 mm and incorporate 4 turns of 1 mm silverplated copper wire.
L1 is lapped one turn from the earthy end, whilst L2 has a tap one turn from the end closest R3.
Ceramic sorts are suggested for the four 1 n capacitors.
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