[Elecraft] OT: SGC Coupler / Small Wire Loops

Thu Mar 27 14:12:00 2003

Wire loop antennas with multiple turns are inherently lossy if ordinary materials are used. When tuned they will also be very narrow banded.

This is a big transmit disadvantage. Not a big deal on receive.

Bands that need that number of turns to get to resonance have a very high ambient noise level. Losing 10 to 20 db on receive will not degrade receive performance on bands where the preamp is usually off and the attenuator sometimes on. 

Ten db loss on transmit IS a real big deal, ESPECIALLY on bands with high ambient noise level.

Getting small AND efficient on low bands is a real engineering/manufacturing hassle.

73, Guy
K2AV 
> From: "Martin AC6RM" <[email protected]>
> Date: 2003/03/27 Thu PM 01:52:04 EST
> To: <[email protected]>
> Subject: [Elecraft] OT: SGC Coupler / Small Wire Loops
> 
> <I posted this on rec.radio.amateur.antenna -- I got a couple of replies
> (I saw the 80m spiral loop and the mag loop, and a comment that multi-turn
> loops are generally receive antennas and tx antennas are single-turn) but
> nothing on this particular design that SGC is touting.  Hoping someone on
> this list has some wisdom...>
> 
  ...snip...

73, Guy
K2AV