tags: noise source, zener For measuring the noise figure of amplifiers in a 50 ohm system, noise source which generate Gaussian RF white noise are often used. Here I present…
tags: noise source, zener, BFR93A Some modifications of the broadband noise source presented previously. This second version is based on a two-stage amplifier, with the same BFR93A transistors. The difference…
tags: VHF portable antenna, DIY antenna, cheap antenna Here I present a portable Yagi type antenna for the 2 m band, i.e. 144-146 MHz. This is very easy to do,…
fig.1 tags: Baofeng UV-5R, NA-771 Nagoya, comparison Here I am comparing the SWR of the original antenna with that of the obviously counterfeit Nagoya NA-771 antenna.As can be seen in…
tags: balun, long wire antenna Here I show my realization of a 1: 9 "BalUn" (actually a UnUn) for the 3-50 MHz band based on two FT114-61 toroids. The use…
tags: yagi antenna, 70 cm, cheap, simpleThis Yagi antenna that I present here was developed with the aim of capturing signals between 430 and 440 MHz from amateur radio satellites.…
Measured sensitivity of a UV-5R is made as follows: an LF signal of frequency 1 kHz is FM modulated over a width of 10 kHz and sent to the input…