The EMTECHs have a very sensitive superheterodyne receiver. A variable bandwidth crystal filter is included in the IF chain. An optional fixed-width audio filter is available and recommended. The IF/ audio filter combination allows good selectivity during crowded band conditions.

For me, the EMTECH step-by-step "build then test" process was especially helpful. The instructions are not as detailed as the old heathkit manuals, but they cover the necessary steps very well. In addition, the builder assembles a section of the transceiver, then tests that section. So as more and more components were added to the board, I wasn't worrying that I'd make some mistake that would be difficult to find later. This "build a section and test" process also helped me to understand how the transceiver works.

The audio filter option was included with my kit. The Instructions include an explanation of how to vary the filter peak frequency and to add gain. I chose a center frequency of about 650 Hz with no additional gain. Actually, I played with this feature a little after the transceiver was completed. It was fun to change a few parts, then to observe the results. The audio filter is a nice option.

Alignment and testing of the complete transceiver requires simple equipment. A tuner with a dummy load and power meter, a volt-ohmmeter and a calibrated receiver will do the job. I used a frequency counter instead of the transmit frequency, since this is also the the sidetone heard when transmitting. The instructions cover two methods for making this adjustment.

The NW80/20 rigs are designed to fit into the inexpensive Radio Shack 270-253 case. EMTECH also offers a fancier custom case. I have rigs in each.

Now it's confession time. The NW20 rig tested for this article was actually built by my wife, Ellen. She won the kit at Dayton, and decided to build the kit herself, even though she never used a soldering iron. I looked over her shoulder occasionally, and confirmed her tests results as she completed each section. Her work passed the "smoke test" with no problems.

The EMTECH 80/20 rigs are fun and satisfying to build, and they work very well. They are the single-band workhorses in my shack.