Elecraft K1 - a *really* long time review

NOTE: This review was originally written by me in November 2009, just over a year after I started working on shortwave. The market for QRP radios was extremely limited and not comparable to the offerings available in 2025. I was a student living in Sarajevo, and importing anything would mean extremely high shipping + customs charges.

Over the years, I have added the built-in automatic tuner, internal battery and noise blanker modules, and have upgraded to a 4-band filter board.

The K1 was discontinued by Elecraft in 2017.

One year and about 1000 QSOs later

QRP is what actually got me started with ham radio. I was fascinated that you can reach distant stations with a few hundred milliwatts and simple wire antennas. Having read so many good things about Elecraft, I decided to order a basic K1 two-band kit (probably the most popular, 40 and 20 meter version). Building the kit was extremely easy because the geniuses behind Elecraft designed the K1 to be an easily reproducible kit with an outstanding manual. Operating the K1 is a joy. I mainly use it on 40 meters with an inverted v antenna just a few meters above the ground. I also had the chance to try my K1 with real antennas – a two-element Moxon for 40m and on another occasion on a four-element 20m monobander. For practical operation, the basic K1 has everything you need - variable bandwidth IF filters, an attenuator and RIT/XIT.

I think that the designers of the K1 put in a lot of thought into the whole concept. The VCO voltage is double-regulated, critical VFO components have opposite thermal coefficients to partially cancel-out temperature-related deviations, latching relays are used to save just a few milliamperes.

The K1 has a 4-pole, variable crystal filter that has three user-programmable bandwidths (set from the menu – very simple) which can be changed at any time.

If you are concerned about frequency drift, this is definitely not a a practical issue. There is a short warm-up phase when turning on the K1, where it drifts a few hundred Hz in about 30 seconds or so. After that, it is completely ready to operate. You won’t also see no noticeable drift during longer QSOs. Things that can influence the frequency stability are extreme heat (direct sunlight) and bending the case. If you bend the case a little, you will hear a small but noticeable drift but this is not really annoying.

How I like to use it

The K1 has a built-in CW keyer and two memories. In mine, I have programmed my callsign and a “reply message” – R 599 73 TU.

I know many people wouldn’t like this, but I have worked a lot DX stations using only the K1 without a keyer or paddles. If the DX has a pileup going, I can shorten the message playback by pressing any button after sending R 599 so the next caller can get a shot at the DX. I think this feature is great.

The output power can be adjusted from 0 to around 7 Watts from the menu, in steps of 100 mW. This allowes for fun experiments with really low power and I have enjoyed noting down the power levels for some QSO-s in my logbook.

I also used my K1 to match my antennas in the garden. It’s easy to take out all you need is a small battery (if you don’t have the optional internal battery kit) and an SWR meter (if you don’t have the optional internal tuner) and you can match your antennas with this setup if you do not have anything better available.

Although I had an Autek RF-1 antenna analyzer and a miniVNA at the time, the K1 was still practical for this. This was before the time of the Nano VNA and similar, really low-cost analyzers.

Shortcomings

The thing that bothers me the most is probably the sidetone. The sidetone pitch can be adjusted in the menu from 400 to 800 Hz but the tone produced is too harsh for me personally. A lot of users complained about this on the internet, not just for the K1 but also the K2. For the K2 you can easily find a very good modification but not so for the K1. I tried to build in a small RC lowpass filter, it sounded great but the insertion loss was just too high for me so I reverted it to the original. Changing the sidetone pitch, requires you to also adjust the BFO. This means opening up the radio rather than being able to adjust it from a menu.

The K1 uses a 2SC1969 transistor in the final output stage. The kit has been designed quite a few years back but now this transistor is not being made anymore and because it was extremely popular, a lot of bad imitations have showed up. Elecraft probably still does have a very good stock of these since they are used also in the K2 QRP kit.