Simple VHF Amplifier??

Willen said:

do you mean 145,650 MHz (145.6GHz? Or MHz?)

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panic mode said:

-QRP is good example of using low power to get long connections. getting far with little radio power is actually not a problem, challenge is obstacles. at frequencies sufficiently high (100MHz is high) radio waves propagate more or less straight (line of sight). this is why you will not hear FM radio (88-108MHz)from town that is 200km away or on other side of the world - even though they use powerful transmitters, you only pickup local stations.

-HAMs often get connections around the world using only low power and reflections of ionosphere - when working with lower frequencies (up to some 20MHz or so and when ionosphere is low.
I am not surprised about getting 230km range at 1 or 1.5W, but getting that range using 143MHz would need line of sight. imho there is either a depression between both locations that are 300m above sea level or some other factor that was not mentioned (perhaps another repeater?).

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panic mode said:

the idea is to use small power to make long distance connections. ideally the small power shall be 5W at transmitter output or less.
antennas are the key. so they go to great length to make sure the antenna is high gain and matched perfectly.

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panic mode said:

he is from Europe there is no decimal point, it is decimal comma.
for someone used to write in that format (ie. pi=3,14) it may be all too easy to forget that
on the other side of the world people are used to using dot (pi=3.14).

QRP is good example of using low power to get long connections. getting far with little radio power is actually not a problem, challenge is obstacles. at frequencies sufficiently high (100MHz is high) radio waves propagate more or less straight (line of sight). this is why you will not hear FM radio (88-108MHz)from town that is 200km away or on other side of the world - even though they use powerful transmitters, you only pickup local stations.

HAMs often get connections around the world using only low power and reflections of ionosphere - when working with lower frequencies (up to some 20MHz or so and when ionosphere is low. that is why you get more AM stations, specially at night when ionosphere is lower (and incidence angle changes).

I am not surprised about getting 230km range at 1 or 1.5W, but getting that range using 143MHz would need line of sight. imho there is either a depression between both locations that are 300m above sea level or some other factor that was not mentioned (perhaps another repeater?).

Click to expand...

panic mode said:

I am not surprised about getting 230km range at 1 or 1.5W, but getting that range using 143MHz would need line of sight. imho there is either a depression between both locations that are 300m above sea level or some other factor that was not mentioned (perhaps another repeater?).

Click to expand...