Yes. An amp that takes you up 10:1 in power, e.g. 20 watts to 200 watts or 100 watts to 1,000 watts, makes a 10 dB difference in signal -- just a bit over one S-unit.
I pointed out the beacon resource as a good example of how often that extra power is not needed on H.F., especially for narrow bandwidth modes. Otherwise we would not have QRP enthusiasts using simple verticals with DXCC awards. I liked the idea that new Hams can listen to the beacons themselves and decide whether the power difference is all that important. 73, Ron AC7AC -----Original Message----- That's a good resource but it doesn't tell the whole story. An amplifier will give you around 10 db improvement in signal on the other end. That's more than the difference between a dipole and a five element monobander. As little as 3 or 4 db will make a significant difference when competing against others in a pileup, and of course as little as 2 db can make the difference between no copy and clear copy if your signal is right at the noise level. http://www.ab7e.com/weak_signal/mdd.html Hams have turned their noses up at amplifiers for decades, but the reality is that an amplifier and a decent vertical is often a more cost effective way to put out a good signal than is low power to a tower and big antenna ... especially if you live in a low noise area where you don't need lots of discrimination to hear DX (and even then there are compact receive loops that make possible alternatives). Dave AB7En 3/22/2013 12:49 PM, Ron D'Eau Claire wrote: > For the newer hams, here's an interesting resource that will > demonstrate to you what a DX signal sounds like at 100 watts, 10 > watts, 1 watt and 0.1 watt. All you have to do it tune into the beacon > frequency of 14.100, 18.110, 21.150, 24.930, 28.200 using CW mode and > listen. The beacon stations in 18 countries take turns sending call > signs and 4 dashes, each dash in descending power level. You might be > amazed at how often you can hear 10 watts or less clearly from half > way around the world when the band is open. > > When the band is not open, a kilowatt doesn't get through. > > A complete list of the stations, locations and the transmission > sequence is > at: > > http://www.ncdxf.org/beacon/beaconSchedule.html > > IIRC, all of the stations use a simple 1/4 wave vertical antenna. > > I'm not saying that an amplifier isn't useful, but this helps put the > advantage of having one in perspective. > > 73, Ron AC7AC ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
