Electronic telegraph key based on capacitance sensors for KX2 and KX3 Elecraft transceivers.

So here they are! Capacitive CW touch key for KX2 or KX3.

This is the second version.
The first version did not stand the test. With a nearby transmitter, interference was induced. The device gave false signals. I reworked the circuit of the device. I also redid the board layout. An active protective circuit has been added. Now the device can withstand the high-frequency voltage of my 1 kW amplifier with a bad SWR. 

Advantages of the device:
- no mechanical moving parts,
- does not need adjustment,
- not afraid of dirt,
- speed depends only on the speed of your fingers,
- silent,
- consumes very little power.

Disadvantages of the device:
- you can't work with gloves on.

Video of the device can be viewed on Youtube.


The distance between the pads is 16 mm.

I'll send you the key fully assembled and ready to go. Also included will be 2 bolts for mounting. No modification of the transceiver is required.

You can buy the key for $40 with free shipping. Write me or click the button below. Please provide your exact mailing address and name.

For people who want to use the key for another transceiver or as a desktop, I leave the pinout of the connector. Attention: the key does not allow reverse polarity of the power supply and the supply voltage is greater than 3.3 Volts. When the key is pressed, the outputs are attracted to the ground. The key already has a connection of the outputs to the positive power supply with a 10 kOhm resistors. The maximum current at the outputs is 20 mA.

Some product reviews:

- The key arrived today. Lightweight, sturdy, and very responsive. I love it!! Thank you for a great item, it will get a lot of use I promise. I am also going to post a review about it on my blog in the next few days if you don't mind, and I will include a link to your website too. You can find the blog on www.w0bnc.com 73 (Bob W0BNC)

- This capacitive keyer is great! It's more robust than a similar model from an American QRP company and the two mounting screws were even included (not so with the other company). This keyer and the I/Q board from UC6UAA have been a very welcome upgrade to my KX2, I highly recommend both products and the seller! (Travis K3XQ)

- Received the key last week here in Switzerland. Have been on a SOTA trip yesterday (HB/BE-155) to test the key. Worked without any troubles. Thank you again for your great work.vy 73 de Tom.
I have attached two photos, where I have the key in use. Have made 7 successful sota activations in the meantime with this key.. Will make another actication tomorrow. (HB/SG-057). The key works great at my CW speed (about 85). It also works when using at slower speeds. I rarely use speeds over 90 (HB9EVF)

- Excellent product and received in less than a month.
Perfect sensitivity during cw operation. A valid alternative to the original elecraft key. Well done Evgeny. Thanks! 73 (IK6ZDF Giac from Italy)

- Dear Eugeny. I got the key today! All perfect.Many thanks. I will recommend your key.
Hope you get rich!! :) (Miguel EA1BP)

- I now have the capacitive touch key for KX2.  I had never used a capacitive touch key before, so it took me a few minutes practice to get used to it.  But, it works flawlessly, and it attaches perfectly to the KX2.  Thank you for a great key. Thanks again and 73 (Anthony WW4N)