by M B Hamilton » Wed May 25, 2011 6:22 pm
The idea is to have any amplifier as close to the antenna as possible to maximize the likelihood of amplifying an actual tv signal rather than interference. Some compact antenna (don't know about ALL) have a built in amplifier. To save the owner from having to run a power cord up to their antenna the antenna maker may use a special cable coupler that incorporates a power port. That's the "power injector". You'd plug their wall-wart into that power port and its low-voltage would be transmitted to the built-in amplifier via the coax. So, unless you have the model antenna the power injector was made for, and the wall-wart, it would be useless to you.
Yes, a non-amplified antenna with an external power amplifier will do the same thing. Maybe even better if it is a better antenna than the one that the power injector came with... just no way to tell for certain as we don't know what that antenna is/was.
Yes, you could easily use an external amplifier with one of Bob Henry's redneck antennas. But, if you have an non-amplified antenna first check to see if you need an amplifier. If you do mount it as close to the antenna as possible.