ALP 620 as a transmitting antenna

[Jim Rillie]

Hello group,

 

Is anyone using this antenna for comms? I am using a dipole at the moment for our crew comms signal from a DCHT to M2R receivers.

Range is generally less than the incoming range of a DPR. Would like to get more usable signal range out to the crew with their M2Rs.

Since the ALP 620 has a lot more gain than a dipole, will using  the shark fin give us noticeably more range?

Since the 620 is passive, I think the 50 mW signal will not harm the antenna. Or am i wrong?

Best regards,

 

Jim Rillie

[Patrick Farrell]

Perfectly fine to use as a transmit antenna. You'll experience more range in the forward direction but less range when off axis. Just got to remember to point it where you want it.

[Jim Rillie]

Thank, you Patrick. That is what I thought. I do currently adjust my receive 620s for that very reason, also using back pattern null for

interfering signals.

 

just like using a cardioid pattern on a mic to advantage.

[karlw]

For future reference: any passive antenna is reciprocal: it has the same characteristics (pattern, gain) as a receive antenna and as a transmit antenna. Most active antennas cannot be used as transmit antennas since the amplifier only works one way. There are recent active antennas, like our ALP690, that can be used either way. When powered, it is an active antenna, and when not powered, it is a passive antenna and can be used that way for transmitting.