On Jul 25, 6:23*pm, Ross Archer wrote:
I'd like to try building an *untuned* loop amplifier covering HF and
wonder if anyone has seen links on this.

The thinking so far is using a pair of 2n2219a bipolar transistors
running a few hundred milliamps, with their collectors driving
opposite ends of an RF output transformer, and a reasonably large loop
(say 1 meter square or more).

I'd like the output to be "hot" enough to compensate for a losses from
a nice long run of cheap cable-TV type coax cable (through which power
will be fed up to the amp). *But not so "hot" as to create distortion.

Anyone here have experience with this sort of project? *If so, is the
2n2219a a stupid choice? *Would I be better with JFETs, and would a
single-ended amplifier work almost as well as a balanced amp? *(My
thinking is the balanced amp would potentially be quieter.)

It would be fun to try this, and my junk box is overflowing with
parts, so why not?

-- ross

Add-On Loop Antenna Amplifier -by- Bruce Carter
http://www.hard-core-dx.com/nordicdx...op/amamp2.html

Balanced Loop Amplifier
http://jlkolb.cts.com/site/dif_fet.pdf

Loop Antenna with Balanced Amplifier
http://www.qrss.thersgb.net/active-l...g-antenna.html