After a lengthy hiatus from any serious building of electronic kits, a new offering from Doug, KI6DS at QrpKits.com caught my eye recently. Dubbed the “Survivor,” it’s a 75-meter SSB/CW kit designed by famed QRP designer Steve “melt solder” Weber, KD1JV. The Survivor owes its birth to the desire to duplicate the utility of a long-out-of-production kit offered by the NorCal QRP Club called the Epiphyte. On the Survivor web page, Doug describes how the designer of the Epiphyte used it for near-vertical incident sky-wave (NVIS), a reliable technique on the low bands for making contacts within a few hundred miles.

This kit appealed to me for a number of reasons. First, it’s SSB. I have to confess that, despite being a QRP’er, I don’t care much for CW outside of contesting. I’d rather ragchew using voice or data. Second, it’s fairly compact–not Altoids-tin compact, but small enough to fit in my backpack. Third, when I’m out on the trail in the middle of nowhere and out of VHF range, it gives me an option for being able to communicate in an emergency. Fourth, I haven’t built any rigs for several years and this looked like a fun one. So, I bought the kit.

Now, there are two ways to build a radio kit. One way is to just stuff the board with parts, wire everything together, and hope it works when you’re done. The other way is to study the schematic and the circuit description and build the radio in stages (the VFO, the product detector, etc.) and test each stage as you complete it. I’d done it the second way once before, quite a few years ago when I built the Wilderness Sierra multiband QRP CW rig. Not content to keep all that I learned to myself, I documented the experience as Elmer 102.

Here I’m going to do the same thing with the Survivor. If you’d like to follow along, you can download the construction manual via a link at the bottom of the Survivor web page. I’ll probably refer to it from time to time, and you’ll need the schematic to really follow along.

Aside from the construction manual, there’s another good resource for builders of the Survivor in the form of the Hendricks_SSB Yahoo Group. When I joined, the first things I found were posts describing some corrections to the construction manual and to the schematic diagram. Builders who went before me did a great job of reviewing the manual and pointing out the needed corrections.

So, the next few pages will summarize my experience as I build the Survivor. Let me know if you have any comments or see any errors I might have made. Enjoy!

Before We Begin

Regulated Power

The VFO

The BFO

TX/RX Switching

Tune Mode & CW Sidetone

More TX/RX Switching Stuff

The Balanced Modulator and Crystal Filter

TX Mixer and Amplifiers

The Receive Mixer

The Product Detector and Audio Amplifier

The Transmitter Power Amplifier and Final Adjustment

7 thoughts on “Building the KD1JV Survivor 75m SSB Kit

  1. Dear Dave,
    FInally I just bought the survivor which you built for Ed Kacura. I am getting it in a week or so.
    He said the midpoint is around 3.81 giving full 10w there. I would need to get the 10 w at around 3.76 . Do you suggest I move the frequency range lower to have the midpoint there or is it not worth it as 3.76 is still high enough to get close to full 10 W.. Ed measured it and said that at 3.72 he got 3w at 3.81 10w and at 3.9 8w. As I do not have a power meter just wonder what you think it is at my required frequency range.. here frequency limit is 3.8 anyway .

    Will add a loudspeaker internally to it.. if you have any suggestion?

    Best wishes and looking forward to see your work. Cheers and thanks Klaus

    Reply
  2. Hi Klaus,

    Actually, I didn’t build the rig you’re getting. It must have been one of the other guys on the Survivor list–perhaps Dale Putnam W7CS?

    As far as the midpoint frequency goes, you might want to move it lower. I’d try to measure the RF output somehow, so you at least know you’ve got the peak in the right place. There are techniques for making power measurements using a voltmeter (like with a diode probe). If you do a web search, you’ll get plenty of hits.

    Congrats and good luck -

    Dave NK0E

    Reply
  3. This sounds like a fun kit — thanks for publishing your notes! Can you tell me the frequency range of the Survivor? For FCC General licenses (like mine), the 75m band allows us to use 3.8 – 4.0 mHz for voice, but the comment above about the tuning midpoint being at 3.81 makes me wonder how much of the Survivor’s frequency range can be used by Generals.
    Paul

    Reply
    • Hi Paul,

      The midpoint of the frequency range can easily be moved to wherever you’d like by adjusting the number of turns on T5, the VFO inductor. So you can move the frequency to better cover the 75m voice band if you’d like.

      Dave

      Reply
  4. Dave,

    Thanks for the great blog/build — I followed your process when building my kit and it was really educational.

    I too have noticed that the “tune tone” is REALLY loud, particularly when I am using my headphones. Did you ever tweak your kit to reduce the intensity of the tone?

    73,
    Myles, VE7FSR

    Reply
    • Myles,

      Thanks for the note. Glad you found the writeup useful. I will confess that I never did try to do anything about the loudness of that tone. If you do, leave another comment and let us know what you did.

      73, Dave NK0E

      Reply

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