[Elecraft] KX1 Mod's & Suggestions

[Gary Thurmond]

I love my KX1 s/n #953,  Have had no problems. Elecraft documentation is 
the best I've ever seen.
Main use has been working on my CW copy and some SWL while laying in bed 
at Odark:30 unable to sleep.
Really appreciate the "Keyer Test Mode" to practice with the KXPD1. 
Elecraft thought of everything.

I have come up with a few modifications or suggestions for consideration.

1. 1 Amp Pico fuse between D2, D3 and S2 Power On/Off.
2. Optional resistor across D3 so BT1 can be charged externally.
3. Second thumb screw and threaded insert for the paddle.
4. Split the AF circuit so the AF Gain control is between a high gain 
low noise diff amp and the AF output. Increase the overall gain a bit.
5. Apply the output audio through two resistors to Tip & Ring. Or output 
audio to Tip and then ground Ring., float Body so Mono Ear plug or small 
speaker can be used.
6. Last but not least,  80/75/40 meter version for us night owls.

I have done 1 & 2 and will do 3, 4, 5 & CW Tuning Indicator next. Looks 
like there is room on top of  U3 and U4 for a small SMT board to do the 
audio mod.
I hope Elecraft will consider  # 6 as a alternate version of the KX1.

The Pico fuse was installed by cutting the large trace on the bottom 
edge of the board near R23 and soldering the fuse across the cut.
The resistor to enable external charging was soldered across D3 on the 
top of the board.
I used 82 ohms 1W (NTE 1W082). small ceramic.
82 ohms is a good compromise between charging with a plug compatible 
Icom BC-25U (IC-2AT) wall wart or 13.8 volts external power.

73,  Gary   W6STR