Feld-Hellschrieber: What the Hell is that?

     Today I want to pick on a mode that is the German equivalent to an American's fax machine. Many of you ham operators have heard of Feld Hellschrieber, or simply called Hell. Feld Hell has its roots in the early days of WWII, and although its popularity has died off due to newer, reliable modes like FT8, many ham radio operators continue to use this mode.

    In 1929, Rudolf Hell created a facsimile/fax-like mode that would be integrated into the German army in WWII and going into the Cold War. Although it is not widely used commercially, it has been adopted into the amateur radio community. Many more Hell modes have come into existence, like Hell 105 and Slow Hell. There are many differences between these modes, such as OOK and FSK modulation, but they are all related in the fact that they are all Hell modes.

   

    After seeing my FT8 signals appear on PSKReporter, I figured I would try other modes, more specifically, Hell and RTTY. My RTTY signals were heard on the West Coast, but in checking other sites, I couldn't find my CQ calls sent in Feld Hell. That doesn't mean that I will give up though! I will keep pumping out signals until someone answers my CQ calls or I get spotted.

    I might try Hell on my Pixie kit, as Feld Hell is specifically modulated in OOK (On-Off Keying), just like other CW modes. Using an external switching circuit, I can manipulate the AFSK signals that come from my computer's fldigi software to key the little transceiver using an optocoupler. More information on that can be found in this PDF. In the future, I hope that this is possible.

    Because of my interest in Feld Hell, I decided to join the Feld Hell Club. I was recently accepted and was presented with my member certificate! So far, I have access to 40, 15, 12, 10, and 6 meters, but I'm hoping that I can get access to all of the HF bands, and I might have just the solution. I'm planning to add a DDS VFO to a Pixie so I can surf the bands and send CW or Feld Hell. I might throw on an amplifier in the future, but we'll see what I can do with QRP.

    In the end, is Feld Hell worth it? In a nutshell, yes. It is a fun mode that acts like fax, and it can easily be used on CW only transmitters or transceivers.