re [Elecraft] Things I would do differently when I next build a K2

[Bob 'bz' Zinn]

My thanks to all who have commented on my rather lengthy post. I 
responded privately to many of them.

> Date: Fri, 12 Jan 2007 11:03:22 -0800 (PST)
> From: "Fred (FL)" <ncsailors at yahoo.com>
> Subject: [Elecraft] Things I would do differently when I next build a K2

> Some good ideas - If I did it again:
> 
> - I would not PAINT any parts or PCB's - it would
> degrade you K2's value, on the market (IMHO)

I am NOT worried about the market value. If I were, I would never buy a 
K2 because even the best built ones resell for much less than the 
unbuilt kit prices.

> Just carefully, in cups or plastic tubs - place all 
> the parts ahead of time.  Easiest way to keep track
> of parts!

I did all that. (I used the black anti static foam pads to separate and 
hold components.)

I also double checked while installing. I STILL ended up short on a 103 
and long on a 102 cap and am in the process of looking for the needle in 
the haystack.

It is NOT one of the parts with a visible label. I suspect that 
somewhere there is a bypass that is not doing everything it should be 
doing.

I also have some weak spurs on receive with a dummy load for an antenna. 
  Perhaps related :)

Tests last night showed that signals in the 21 through 73 MHz range are 
getting INTO the box through the front panel, around the mike plug and 
phones jack (two items that are not grounded to the front panel!).
For example when listening on 3780 cw I get response to signals (a sig 
generator with 350 mv output to a bnc to banana jack adapter held near 
the front of the rig) on (at least) the following frequencies:
74.469, 73.325, 65.768, 48.383, 38.552, 30.995, 21.165, 13.608 (all MHz)
I didn't check all but 48.383, 30.995 and 13.608 were 'reverse' (tuned 
as if they were being received in reverse mode of cw.

Response to a signal at the fundamental frequency (3780) coupled in the 
same manner was much weaker, almost undetectable.

This exercise started when I noticed a spur (actually a series of spurs 
across the band) at ~7.118 MHz that could be somewhat attenuated by 
cleaning paint away around the keyjack and making sure it is well 
grounded. 'Somewhat attenuated' but still there. It came back much 
stronger when I hooked up headphones or a mike to the front jacks.

-- 
-bz-    "it is a beautiful day to be alive, isn't it?" [every day]

N5BZ+ecr at chem.lsu.edu
http://chemistry.lsu.edu/bz
225-578-5381