Steve's ATS3b Web Page

The ATS3b is a 6 band transceiver with a DDS dual VFO, and a full 5 Watt output that fits inside an Altoid's tin and weights only a few ounces.  The radio was designed by Steve Weber, KD1JV, a QRP-ARCI hall of framer, who has kitted various versions of the ATS (Appalachian Trail Series) rigs for several years.  A few months ago (March 2008) Steve made up six additional kits and I was lucky enough to acquire one.  At $190, considering the HF frequency coverage, it is the cheapest QRP rig out there in terms of kilohertz per dollar.  What is amazing is that it appears to have a highly competitive receiver.  This all makes it a highly desirable QRP transceiver for field use.
 
   
   
   
   
   
   
This is the peak detector that I used to accurately measure output power of the transmitter.  With the .6 Volt drop of the IN914 and its peak inverse Voltage,  usable Voltage readings are from about 1 Volt to about 75 Volts.  Using the formula V*V/(2*R) this translates to .01 Watts to over 50 Watts.  It is shown in Solid State Design, Page 146, Figure 7. Long story about the layout.  I wanted a portable mini dummy load and used an RCA audio jack at the end of it.  I rolled some 5 minute plumber's epoxy around it.  The voltmeter and input jacks were also RCA type.  I had so much trouble with inconsistent readings that I got rid of the RCA jacks.  I glued the dummy load directly to the housing and hard wired it into the circuit.
Here is the interior of the peak detector.  One resistor, one diode and two capacitors.
   

 

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