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First, the credits. I am being gently guided by my elmer, W3TS, Mike, as I build this project. Without Mike's help, I'd be a bit lost. Larry, AA3PX, has a deep junk box and helped me out with the preselector capacitor and some crystals. Jim Skalski, N2GO, graciously provided some advice and parts as well. Of course, all the design credits go to W7ZOI and K5IRK, except where W3TS has helped me with some improvements. The Progressive Receiver is an 80m single conversion superhet with other bands added with the use of crystal-controlled converters. My plans are to include 40m, 30m, 20m, 15m, and 10m as I get the converters completed. Progressively! After the receiver is completed, tweaked, and working FB, I want to incorporate a transmitter for a multiband, homebrew transceiver. The project case is a large Ten Tec enclosure with a divided sub-chassis. Most of the receiver will go on the top with the exception of a few converters. The transmitter will go below. Instead of the individual bandpass filters at the front end of the receiver, I'm incorporating a tunable bandpass arrangement, as used in the older Ten Tec Omni rigs. I tune this Preselector Circuit with a 4:1 vernier drive. My Progressive includes a 2.1kHz SSB filter which will always be in line, and a switchable RF amp / 500Hz CW filter. Also included is a switchable four pole CW audio filter. (W1FB design.) This can be switched in and out of the audio line, and provides 350Hz, 160Hz, 130Hz, and 110Hz filtering options. I've also included a 6:1/30:1 vernier on the VFO. As I built the receiver, I discovered that I needed to shield BFO and VFO, including feed through capacitors for the power leads; The BFO 12 VDC line was picking up RF from the oscillators. Finally, the BFO was modified to provide LSB/USB switching. |