[Elecraft] KXB-3080 on the air!

[Jerry Karlovich]

I just buttoned up my KX-1's KXB-3080 mod last night and all is 
working FB! Congrats to the gang at Elecraft for the FB piece of 
engineering that went into that. Wew!

However, I have noticed that on 40 meters (metres for you Britts), 
after allowing the KXAT to do it's tuning thing, I get a very high 
pitch tone from the rig itself. I would guess about 3,000 to 4,000 
Hz. The VSWR was 1.4:1 according to the display. That's with the rig 
attached to my antenna. With the dummy load and 1:1 VSWR there is no 
high pitch tone. This only happens on 40 meters when the VSWR is 
other than 1:1 and not on 80, 30 or 20 regardless of the VSWR. The 
tone is so high pitch it's difficult to determine where it's coming 
from. I even tried to isolate it with the rubber end of a pencil 
thinking I would dampen what ever is oscillating. This is only while 
transmitting and not receiving and VSWR is not 1:1 with the dummy 
load. Battery current is within specs. I haven't tried it portable 
since I put it back together so it will be interesting to see if it 
still does it while camping. I just had the thought of what if I am 
also putting out a side band equal to the frequency of this tone? Hump?

Also, tonight I will begin assembly of the K6XX CW tuning indicator. 
Neat deal since I really am tone deaf. Ask my music teacher. I was 
thinking about drilling a hole next to the "Night Light LED" and 
installing an additional small LED in that location. There's plenty 
of room. Also, does any body see anything wrong with not using the 
header connector and just soldering the wires directly to it's PCB? 
It's not like I take this thing apart every week.

Jerry KD5OM, www.kd5om.com