Building my Elecraft KX1 ser#1056

It finally arrived today 10 Mar 05. My Elecraft KX1 ser#1056. The ELECRAFT ULTRA PORTABLE XCVR for 40m/30m/20m.
At this time I did not order the 30m mod kit or the auto tuner "KXAT1" for it. Deceiding to order the "T1"
Auto-Tuner later because I can use it with any QRP transmitter. Inventory has been completed. Just a few
screws missing. Good job Christine.

Here is the PCB with only the 3 SMD's that are factory installed. Look close!
You are just able to see them near the tweezers points. This PCB is a thing of beauty.

Assembly - Part 1

Over the past two days and 4.5 hours into the building of KX1 #1056 Assembly Part 1 is completed.
Each part checked for "height", "value", "placement" before soldering the component.
Then each solder joint is checked before and after trimming.
I know it is probably over kill but I don't want to build it twice!

(L)View of the top of PCB (R)View of the bottom

Resistance Checks on page 26 of Manual.

Next up ! Alignment and Test of Part I

pages 28 and 29
everything checks out ok
The voltage checks.
U1, pin 1 5+- 0.25
U1, pin 3 5+- 0.25
D2, anode: Supply
D2, cathode: Supply Voltage-0.3 Vdc approx 13.06

RMS voltage checks.
D2, anode: <20mV AC 0
D2, cathode: <20mv AC rms 0
U1, pin 1 <20mV AC 0
U1, pin 3 <20mV AC 0
And I did use 3 differant DMM to confirm these readings

Now at 5.5 hrs into the build.

Assembly Part II

Part II assembly completed

(L) View of the top of PCB (R)View of the bottom of PCB

Resistance measurements at the end of Part II.

Build times now totals 11.3 hours. *NOTE* The black background in some of the pictures is the anti-static mat

Next Up Alignment and Test Part II

Alignment and Test Part II has been completed. All functions are operational.
The RCVR mode current might be a tad high (Manual calls for 32ma) at 35.6ma.
Upon further review the KX1 Erratta sheet corrected those Specs to 35ma on page 5.
It is a "HOT" little RCVR.

Assembly Part III

Part III assembly completed

View of the top of ser#1056 along with battery compartment

inside view of bottom of PCB along with battery compartment

Resistance checks on page 54. All okay!

The Final Resistance check on page 55.

Alignment and Test Part III

#1056 Checked out like a dream. Almost like it was chomping at the bit to get on the air.
I used my Elecraft XG1 for final receiver tweeking and the Elecraft DL1 and DMM to measure
the out put power. 20m checked in with 6.87 vrms and 40m with slightly more at8.07 vrms.
Which looks pretty good to me.

Final Assembly has also been completed until the 30m mod PCB arrives sometime next week.
Total build time was just under 20 hours. What a gas!


30 Meter Mod


The 30m Mod arrived in Mondays mail. I wasn't able to get to it until the next day.
From start to finish it took about 2 hours to populate and install. The documentation
really made it seem more difficult then it turned out to be. What a gas.

Here's the completed PCB. Smaller picture. I used my scanner for a close up view.

Here is the completed 30m Mod installed.


Now while I had the case open I compressed the coils of "L2" as recommended by other Elecrafters.
I again used my Elecraft XG1 for final receiver tweeking and the Elecraft DL1 and DMM to measure
the out put power. With 14.0 VDC 20m checked in this time with 7.02 vrms (2.08 watts) and 30m with 8.91 vrms
(3.25 watts) and 40m with 8.75 vrms (3.14 watts). Looks good enough to me.


72/71 de "rc" kc5wa