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A New Line of Transceivers ~ DifX

Transceiver Architecture 2.06


So What Would You Do If You Were the Designer?


OK! OK! Not everyone is a rig designer and there probably are far more hams who are fully capable of building rigs than  than those who can design a rig from the ground up. But as hams we are all users and we can certainly articulate what we would like to see in a rig.
 
Even more so today as the new technology available to us for literally pennies, can  bring a whole new dimension of features to home built rigs. While there are many builders who like analog VFO's and homebrew dial mechanisms, there are many of us who want digital VFO's with their high accuracy and amazing stability. Many of us also like the colorful displays where lot of information is readily displayed--with much of it being in real time. Thus designs must be flexible so all quarters can participate in the project.
 
So as users we can influence what we want to see in a rig and in effect become the rig designer by what we ask our rigs to do.
 
Here is a laundry list of what users might like to see in a homebrew rig:
 
  • Frequency agility and frequency stability (more difficult with analog VFO's)
  • Sensitive receivers and great sounding transmitters
  • Costs that don't involve taking out a home mortgage or selling off one of the kids
  • Ease of construction using common parts
  • Circuit boards or building block techniques for the final assembly
  • Readily available tech help and a strong user support community
  • Multi-band Operation
  • Low power drain
  • Reasonable power output in the 10 to 15 watt range
  • Ability to handle strong signals and AGC
  • S Meter
  • Selectable sidebands
  • Compact size and low weight
  • 12 VDC Operation
  • Let us not forget the digital modes and interfaces needed for the digital programs
  • RF Pre-Amp and/or 10 dB attenuator
  • Well designed Band Pass and Low Pass Filters paying attention to 2nd Harmonic reduction
  • Use the Arduino Mega 2560 because of the large number of Input/Output Ports
  • Fused Input and Reverse Voltage protection
  • DFM ~ Designed For Maintenance
  • CW Capable and Audio Filtering
  • Painted Juliano Cool Blue
  • IF Shift/ RIT
  • Tone Function for Tune Up ( Standard feature of the DifX)
  •  
  • By making this list we are now starting to define our design criteria. Some may gravitate to a single conversion design but the more sophisticated rigs very likely will be a dual conversion design.
 
What did you have on your list?
 
73's
Pete N6QW

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