I just found this on the Elecraft reflector and wanted to know what the common understanding is in this group here:
"Once you can put up dipoles at
least 1/2 wavelength high and in the clear, it starts to get more
expensive to add to your antenna system than it does to add power.
So, assuming you can hear the station(s) you want to work, you'll
often get more from adding an amplifier than you do making a better
Is this generally correct?
The true answer is complicated. It seems the vast majority of people either do not understand the difference between receiving and transmitting requirements, or just want to give a simple answer that can be wrong half the time.
On receiving, unless you get way down into system noise, the only thing that matters is the ratio of signal-to-noise. This is set by the pattern of an antenna and how it responds to the signal compared to noise. Receiving has almost nothing to do with gain or loss, until the system internal noise starts to determine noise floor.
Let me give you an example. My house is in a quiet location. I can take a 2 foot tall antenna and limit on external noise on 160-40 meters. A two foot vertical pretty much receives everything a 30 foot or a 60 foot vertical receives, all I have to do is have a preamp.
This is why people can use very lossy, very poor gain antennas, to work extremely weak signals on lower bands. My best receiving antenna up to 20 MHz have negative gain!
For transmitting, the effective radiated power at the desired directions and angles is all that matters. This is entirely different than receiving requirements.
Let me give an example with a beam. You can have a lossy beam that has poorly constructed traps, but has a clean pattern, and it can receive as well as or better than an antenna with more gain but a worse pattern. The lossy antenna will not transmit as well, but it can hear just as well or better.
So you see, this complicates the answer quite a bit.
If I was on 160 meters through 80 meters (and maybe 40 or 20 meters), a good vertical would transmit very well. It would not be good for receiving. If I wanted to improve things, I would add a receiving antenna system (that could be inexpensive) and an amplifier.
If I was on 40 through 20 meters, a good dipole up 60-80 feet would be a first step. If I wanted to get louder I could add a beam antenna of some type, and that would also help receiving a lot, **or** I could just add a small amplifier and a cheap receiving antenna system.
On 20 meters and up beams are small enough and easy enough that they are a good first step. That certainly is not true on 160, and not likely true on 80 or 40 unless you just want one or two directions.
It is a very complicated question and answer that depends on the environment, the band, and what you want to do. If someone gives you a simple answer, it will only be correct for the specific condition they are thinking of.
I might pay $1000 to gain 10 dB on transmitting with an amplifier. I might have to pay $10,000 to gain just 6 dB with antennas. It might just cost $200 to gain 20 dB better S/N on receive, and it might cost $10,000 to gain 6 dB if In do it with a big transmit antenna.
The only correct answer is it all depends on the band, the location, what you have to start with, and what you want to do. With so many variables, there can't be one answer.
There is one thing for certain though. Anyone claiming a transmitting gain of 1 dB equals a receiving gain of 1 dB is probably wrong in virtually all real world cases, and a whole lot of people think that.