My current interest is weak signal VHF, primarily contests and high-speed digital meteor scatter using the WSJT software. This picture was taken in 2007.

The picture below shows my antennas, which were obtained from M2. I have stacked 9-element 2M9SSB yagis on 2-meters with the top beam at 53 feet and a 5-element 6M5AX for 6-meters at 41 feet. You can read about the construction of my backyard tower by clicking here. Just below the 2-meter rf power divider is a mast-mounted GaAs FET preamplifier. Click here to see inside the electrical box, which contains the preamp (the LNA PHEMT preamp has been replaced) and power handling/isolation relays. These relays are switched with a sequencer in the shack. I had a lot of trouble with 9913 coaxial feedline that resulted in intermittant receive dropout on 2-meters, most likely caused by moisture penetration -- yes, even in the dry New Mexico desert. The main run was replaced with LMR600 with sections of LMR400 above the rotor. The 6-meter feedline is Bury-Flex from Davis RF.

Below is a photo of the operating position as of June 2015, which occupies a corner of a back room. My interest is VHF so I operate exclusively on 6 and 2 meters using an Icom 746-Pro transceiver. The computer operating system is Xubuntu Linux and I always compile WSJT from the source code instead of using binaries. The digital modes are implemented via a RASCAL interface to the rear data socket. Transceiver output is adjustable between 4--100 Watts on both 50 and 144 MHz. For 144 MHz, I run a homebuilt GS23B tetrode 1.5 kW amplifier that is described in detail here. The 6m amplifier is a compact, all-solid-state package from M2 with internal power supply. It has a WSJT mode capable of delivering just under 1 kW; slightly higher power is produced on short duration ssb transmissions. Both amplifiers are located on a home-built, rolling wooden rack at left. Underneath is the home-built high-voltage power supply for the 2m amplifier.

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