Field Radio Kit Gallery: N7KOM’s Pocket HF Go Kit

I couldn’t believe my eyes when I saw it or held it – just how small this kit is. Tim (N7KOM) and I met up in December 2023 when I was on a trip in the Pacific Northwest and he and I stopped for a lunchtime activation.

Tim’s ENTIRE kit for mountain-top activating less his mast and the 9V battery seen in the background. It’s a stark comparison to my KX3 Go-Kit.

His kit is super light and small. I’ll let Tim take up the description from here:

A Pocket HF Go Kit.

by Tim (N7KOM)

There are few pleasures in life more satisfying than making QSOs on a thin wire tuned for a half wave.

One of my favorite radios is the classic MTR3B. At 9.8cm x 6.5cm x 2.4cm it is truly a pocket radio. Everything I need to get on the air fits into an Amazon external Harddrive case. Here’s a breakdown with weight measurements:

  • MTR-3B – 126 g
  • 9V Li-Poly USB-C rechargeable battery + power plug – 29 g
  • K6ARK 3D printed paddle and 3.5mm cable – 22 g
  • Earbuds + external volume control knob – 26 g
  • Trapped EFHW on an RCA connector (matching the radio’s connector) tuned for 20m/30m/40m. 28-32 ga wire on a 3d printed winder. – 42 g
N7KOM’s ultra-lightweight HF Kit

As is, it weighs a total of 323 grams or 0.7 lbs. Add in a lightweight 9 foot mast from ali-express and I have everything I need to make contacts. I could even string the wire on some bushes or the ground if I was really in a pinch.

Other notes

I could reduce the weight and packability further by using shorter cables on the earbuds/volume control as well as the paddle cable.

The antenna winder is a K6ARK 3D printed winder printed at around 70% size.

A 41 g external speaker may also be added to the kit, but it does not fit in the HDD case and must be carried separately.

Here is a video tour of the kit on YouTube:

So there you have it folks -323g of portable HF kit everything included! Check out Tim’s YouTube page or his Microlight QRP Traps on Etsy for your next QRP outing.

Tim’s field kit is now featured on our Field Kit Gallery page. If you would like to share your field kit with the QRPer community, read this post

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13 thoughts on “Field Radio Kit Gallery: N7KOM’s Pocket HF Go Kit”

  1. WOW!

    Thanks for posting this. I am impressed beyond words. Very inspiring. FB!

    (And to think I was so proud of myself for getting my entire station down to fitting into a single backpack. 😉 )

  2. Wow Tim! Loved the kit…

    The traps on an EFλ/2 is an interesting idea. Especially for the MTR3b.

    The small size/gauge of the antenna, all on a winder with everything fitting in that small case… cool.

    Thanks for sharing. de W7UDT

  3. Simplicity at it’s finest. Compared to the side by side with Vince’s KX3, it’s really small.
    Well done.

  4. Ended up putting together a very similar kit for my new mtr3b LCD edition the other day. It has everything I need except for an antenna.

  5. I wonder if we need a new and challenging figure of merit for QRP bragging rights. Rather than “miles per watt” the new goal might be “miles per gram of station”. 🙂

  6. I’m a pretty new operator and I had never heard of a EFHW trapped antenna and I went down that rabbit hole today after reading this. Seems a little tricky to pull off, but obviously a big win with such a small form factor for a multi-band resonant antenna. Nice work! This post gives me a lot of ideas for shaving weight for the SOTA kit I want to assemble.

    1. An easy place to start is to build a 20m EFHW antenna, then add to the “far” end (i.e., not the feedpoint end) a 34 microhenry coil and about 68 inches of wire. Adjust that length as needed to tune up on 40m. That will give you a three band antenna for 10, 20, and 40. That’s probably a lot simpler place to start than a 10, 20, 30, 40. Here’s an example of mine; my coil is physically larger than you might want for SOTA but should be easy to redesign for smaller size:

        1. I just noticed that it may not be clear from my blog post, but you can still operate on 20m even with the coil and wire extension attached. I chose to make it a clip-on for compactness since my coil is fairly large. I guess I should re-do it with a more compact coil and then I could just attach it permanently.

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