Home |
Search |
Today's Posts |
#1
![]() |
|||
|
|||
![]() Just cusrious... What happens if you pipe the output of one radio in to 2 different amplifiers, and then take the output of the two amps and send them to two identical vertical antennas spaced a half wave apart and with equal length feedlines from the amplifiers. Will the output of the two amplifiers add together in directions where the signal is in phase, or will it act like two different signals and interfere with each other? -Curious |
#2
![]() |
|||
|
|||
![]()
Ponder This wrote in
news ![]() Just cusrious... What happens if you pipe the output of one radio in to 2 different amplifiers, and then take the output of the two amps and send them to two identical vertical antennas spaced a half wave apart and with equal length feedlines from the amplifiers. Will the output of the two amplifiers add together in directions where the signal is in phase, or will it act like two different signals and interfere with each other? -Curious Why would you do that? It's the same as just splitting a single output from the radio. Depending on spacing and phase you can get of variety of different radiation patterns. You don't need to split it between two amps. I split the output from my radio, lag one 90 degrees, put one in one yagi, put one in another yagi and get circular polarization. sc |
#3
![]() |
|||
|
|||
![]() Ponder This wrote: Just cusrious... What happens if you pipe the output of one radio in to 2 different amplifiers, and then take the output of the two amps and send them to two identical vertical antennas spaced a half wave apart and with equal length feedlines from the amplifiers. Will the output of the two amplifiers add together in directions where the signal is in phase, or will it act like two different signals and interfere with each other? there can be issues with phasing if done right no problem but ifyou are not good at getting your coax to just the right tlengths at least that is my understanding -Curious |
#4
![]() |
|||
|
|||
![]()
Depends--, if in phase, Both INPUT, and OUTPUT,
would add (double power, if SAME power on both, Also would add, if 180 degrees OUT of Phase, both Input, and Output. And this would be the same as with Push-Pull amp (both input, and output). but if In Phase, on input, and OUT of Phase, on Output,or vice versa, theoretically, would result in 0 Output. And, if in different phases, probably would make a great interference source!!! (distortion, intermods, harmonics, oddball mixes, ect!) Jim NN7K Slow Code wrote: Ponder This wrote in news ![]() Just cusrious... What happens if you pipe the output of one radio in to 2 different amplifiers, and then take the output of the two amps and send them to two identical vertical antennas spaced a half wave apart and with equal length feedlines from the amplifiers. Will the output of the two amplifiers add together in directions where the signal is in phase, or will it act like two different signals and interfere with each other? -Curious |
#5
![]() |
|||
|
|||
![]() What happens if you pipe the output of one radio in to 2 different amplifiers, and then take the output of the two amps and send them to two identical vertical antennas spaced a half wave apart and with equal length feedlines from the amplifiers. Will the output of the two amplifiers add together in directions where the signal is in phase, or will it act like two different signals and interfere with each other? -Curious I would assume the following: If you use a splitter with an equal length of coax to the two amps, you would be able to get 100 watts out from the radio to be 50 watts into each amp. I would suspect that you would have double the power out to the antenna assuming you used the same length of coax from the amps to the antenna. Of course, you have to deal with impedance problems with the splitting of the coax, for example, two 50 ohm cables would result in 25 ohms to the amps. Not good. then the two 50 ohm outputs from the amps would result in 100 ohms to the antenna, not good again.... -- 73 for now Buck N4PGW |
#6
![]() |
|||
|
|||
![]()
Same affect as feeding two antennas from a single amp. Although it is
sometimes a good way to get more watts/$ Although you have stipulated same feedline lengths there could be some phase delays inside the amps you dont know about (eg filter components). You should of course be able to compensate for this by varying line length. A difference in output power from each will also skew the radiation pattern. If the antennas are thus fed in phase and the amps produce the same power you will get max radiation perpendicular to a line drawn between the antennas and minimum radiation in line with them. You can play with all kinds of phase delay/line length and spacing variations to get a good mix of patterns. They interfere from the standpoint that you get phase addition and cancellation of the two signals combining. This is how driven array antennas work. Do you have a specific application in mind? Cheers Bob VK2YQA Ponder This wrote: Will the output of the two amplifiers add together in directions where the signal is in phase, or will it act like two different signals and interfere with each other? -Curious |
Reply |
Thread Tools | Search this Thread |
Display Modes | |
|
|