Subject: K2 RX performance
Date: Mon, 29 Jan 2001 
From: "Santa Fe" <kt5x@cnsp.com>
To: "elecraft K2" <elecraft@qth.net>

Eric wrote:
 >For most multi conversion RX rigs their dynamic range degrades as soon as the offending signals get inside their relatively wide 1st IF roofing filters (anywhere from 10 to 25 kHz wide) and overload their following high gain stages..


Yes, I listened to relatively weak signal from KL7Y on 160 meters in both the MP and the K2. The MP single signaled it better, but the subject signal "had holes in it." It was ghostlike, making copy difficult. Operators of the MP on DX-peditions have reported this and they have blamed it on the AGC responding to nearby loud stations in the pileup. I think that it is less an AGC and more an IMD problem.

In any case, I was flat out startled at how solid and much louder the same signal was in the K2, easy copy, versus very difficult copy.

Incidentally, K2 filter performance seemed much improved when I improved the headphones that I use with it. I changed from the little Sony stick-it-in-the-ear fones to serious business low distortion high sensitivity phones form AKG. The difference is sound was HUGE, especially in narrow filter positions. I suspect the response curve of the little fones is anything but flat.

72,
# 700
Fred
W5YA


Subject: [Elecraft] 160 meters, QRP
Date: Sun, 28 Jan 2001 
From: kt5x@cnsp.com
To: "elecraft K2" <elecraft@qth.net>

... now a few words about the radio performance on 160
.

This morning I awake to an arctic landscape, and awe of a little radio, the K2.

Last night on 160, and the night before, noise levels across the country must have been very low. How else could stations only S-5 here hear me? Very few stations I called did not respond... eventually. I even called CQ and got answers.

Talk about dynamic range; the radio was entirely unaltered by nearby S-9 plus 40 db signals. I had the MP on along side for comparison and, I hate to admit it, the K2 heard weak signals amid the big guns... better, MUCH better, and the MP is good!

Forty one states were heard from here in New Mexico (without receiving antennas) and every single one was worked, no exceptions. But the last couldn't be topped so I shut it down after that. Barely copiable and not moving the S-meter was KL7Y. Without a thought that he might hear me I tossed my call sign at him. He hesitated, then sent "?"

Startled I called again more seriously, and he answered, "W3?A" That was close enough for me. I got real serious, slowed down, and sent very carefully, and by gosh he got it!

What the H*** is THAT guy using to hear with?????

Thank you Elecraft for one bleep of a radio!

73,

Fred
W5YA (op: KT5X)