N4CF K3s Transceiver Assembly

Best viewed with Mozilla Firefox or Google Chrome


Browse these photos to see how I assembled the Elecraft K3s transceiver kit. No soldering was required – only mechanical assembly – but the kit contains some 300 parts, including factory-built modules and mounting hardware.

April 4, 2016 – Assembly bench setup

While waiting for the K3 kit to arrive, I set up my electronics workbench with an anti-static mat and static-discharge wrist strap. The mat is a large sheet of conductive foam. The coiled green wire on the right plugs into a wall outlet to connect the mat to ground.



April 5, 2016 – Transceiver delivered

UPS delivered the 23-pound package just after 2PM, and I spent the the next two hours unpacking and organizing everything. This was a non-trivial task, as the kit comes in multiple cartons with individual modules wrapped and taped in anti-static bubble wrap. Here are the opened cartons.

The next step was to inventory the parts. These range from tiny screws and washers to large modules. All the electronic modules must be unwrapped and handled on the anti-static mat, with the static-discharge strap wrapped around my wrist.

Measuring the mounting hardware was tedious. Screws and standoffs can vary in length by as little as 1/16", and the instructions warn that using too-long screws can damage or destroy parts! Careful measurement is essential. I used a steel rule with 1/32" and 1/64" graduations, and a dial caliper.

Here is an example of the hardware. All the screws in this photo – plus hex nuts, standoffs, and two styles of lock washers not shown – came from one large bag. Some screws have flat heads while others have rounded "pan" heads, and the two types are measured differently. All needed to be correctly identified, measured, counted, and segregated.

Tomorrow I hope to assemble the transceiver, or at least get a good start on it.



April 6, 2016 – Transceiver assembly


11:00 AM

With the parts inventory complete, the kit is ready to assemble. This photo shows the collection of modules and parts envelopes, excluding the chassis sheet metal, the main PCB assembly, the 100W amplifier, and several transceiver options. Whew! Let's see how far we get in the next few hours.


3¾ hours

The front panel PC board holds the display, pushbuttons, and VFO encoders. The DSP (digital signal processor) board attaches to the rear of the front panel board. This assembly then is attached to the K3's metal front panel, shown here complete after 3¾ hours of work.


5¼ hours

Next came the RF board and modules that plug into it. The front and rear panels attach to this board, and additional modules plug into it and attach to the rear panel.


8¼ hours

I attached the left side panel, and installed the ATU (antenna tuner unit) on the RF board. The vacant space on the RF board and the large hole in the rear panel will be filled later with the 100W amplifier.



April 7, 2016 – Continued assembly

A doctor appointment plus a visit to a hospitalized friend, then lunch with Louise consumed much of the day, but I got back to the transceiver by early afternoon.


10¼ hours

I installed the front panel shield and the case side panels. Two PC boards are plugged into the RF board, screwed to the shield, and cabled to each other and the RF board. Not visible in this photo are the carrying handle on the left side panel and four rubber feet right side to support the K3 if set down while carrying it.


Smoke test!

After a resistance check at key points, the assembly instructions said to conduct an initial power-on check. The display and LEDs lit up as they should, and nothing smoked – all very good signs!


11¼ hours

The power amplifier shield was next. The actual amplifier is still wrapped in its anti-static plastic, and won't be installed until after some tests and alignments are performed at low power. The narrow green PC board with a white sticker in the amplifier cavity (yellow arrow) is a jumper that connects the low-power output to the antenna tuner. Ultimately the amplifier will replace this jumper board.


13¼ hours

I mounted the speaker on the top panel, but that won't be installed until later. The two-piece bottom panel was next. This holds the feet and a flip-down tilt stand.

I knocked-off at this point because it was late, and the assembly manual said, This completes the assembly of your K3s/10 transceiver. Next perform the Initial Test and Calibration procedures below to ensure your K3s is operating properly.

Sounds like a lot to do, so I'll start fresh tomorrow.

April 8, 2016 – Pause

I didn't make much more progress today due to various unrelated factors. I hope to finish tomorrow.

April 9, 2016 – Final assembly, initial testing


19 hours

At last the K3s is complete! I spent several hours creating a temporary test setup, then conducted the prescribed configurations, calibrations, and tests. After these, I installed the 100W amplifier, and ran some more calibrations and tests.

After everything checked out, I connected the hand microphone and made my first contact – W4T, national Parks on the Air Special Event station TR-12 in eastern Tennessee on 40 meter SSB. He gave me a 59 signal report, and said the audio sounded fine.

This photo shows the test setup, with power, ground, and antenna cables strung across my desk between the keyboard and the monitor.


April 11, 2016 – installed in shack

After coping all weekend with the K3 and cables cluttering my desk, I bit the bullet, and re-routed the cables, then slid the K3 into its new home, the hutch bay. It's fairly convenient there, but I can expect I'll be moving the mouse pad occasionally as I use the rig.

I ordered the matching P3 panadapter today. This "band scope" displays signals over a wide swath of the band. I used the PX3 panadapter with the KX3, but sold it when I retired that rig. After only two days of operating without one, I concluded that seeing the "big picture" was a benefit I needed right away.


Updated February 17, 2017