Home Brew Night 2012

The first 2012 meeting of the San Lorenzo Valley Amateur Radio Club was held on Friday the 13th! Traditionally the first meeting of the year is Home Brew Night, where members share their ongoing projects and plans. Photos by Kerry Veenstra.

Plumbing—um, that is—Loop Antenna by Dwight KJ6MUL.
Yes, it works!


JV K6HJU’s HSMM-MESH node resurrects a Metricom/Ricochet poletop-radio case. The case has an RF seal! It has a weather seal! It’s made of powder-coated forged aluminum!


The circuit board of a WRT54GL just fits in JV’s Metricom enclosure. JV added an Anderson Powerpole connector to the circuit board. Not shown: the pilot lamp that is visible through a transparent window.


Rich KE1B showed us his portable 70-cm-to-160-m DXpedition in a box! It can be checked as airplane baggage.


Rich cut the foam to provide a place for everything. (Except the laptop and the Buddipole Antenna, which are carried separately.)


Highlights: Universal power supply with international power adapters, USB drive with all manuals, tiny iP30 antenna tuner, cheat sheet of Buddipole Antenna dimensions for all bands, and spare batteries for everything (of course!). The system, once set up, is 100% computer controlled.


Glen KG0T likes to use 2-meter repeaters on long road trips, but he doesn’t want to read the repeater directory while driving (good idea!). So instead, he constructed and programmed a GPS-based mobile-rig controller that automatically keeps the rig’s first eight channels set for the eight closest repeaters!


Glen is working on a new version that uses the development board of a Texas Instruments MSP430 Launchpad (the MSP430-microcontroller development kit is only $4.30, folks, shipping included).


Brad N6BHT used a NEMA Type 4 enclosure (Bud Industries model SNB3741) for his HSMM-MESH node. He fabricated two mounting brackets that allow easy attachment to his tower using U bolts.


Kerry K3RRY, who is preparing for a new tower, models his still-pristine hard hat. It’ll get some use soon. (He’s also modeling his UCSC Grateful Slug hoodie. We don’t know why.)


Kerry’s Champion Radio Fall-Arrest Harness (resting on the floor) is connected to a Guardian Double-Leg Internal Shock Lanyard with Rebar Hook. The remaining items in the carrying bag are a 4-foot rope lanyard, a canvas tool bucket, and a canvas tool bag. Kerry already has used this equipment while replacing the 2-meter antenna on the club’s tower (under JV’s supervision). Total cost of Kerry’s safety equipment? About $300. (A bargain when you think about it.)


John AC6SL showed us several low-budget antennas for HSMM-MESH. He used many of these to connect with K3RRY’s node, which is 3 km away with a 24-dBi directional antenna. This one, a parabola constructed of aluminum-foilwrapped manila-folder stock, is placed on the stock antenna of a WRT54GL.


John’s double-parabola version rests on both antennas of a WRT54GL. This one uses slots in blue packing foam to position the sheet-metal reflectors.


John’s Yagi for HSMM-MESH. Once again, blue packing foam positions antenna elements, which in this case are short lengths of solid copper wire.


Brad examines John’s repurposed dish-network antenna. This one uses a bi-quad feed. When in use, the WRT54GL router itself attaches at the feed point.


Carefully cut double-thickness corrugated cardboard helps form this deep-parabolic-antenna-in-a-box. The deep parabola captures 75% of the antennas’ emissions. Longer, surplus, antennas are attached to the WRT54GL. The cardboard positions the router inside the box so that its antennas lie at the parabola’s focal point. The system works well, but it’s not waterproof—unless in a pinch John throws a tarp over it!


John uses a laser pointer to confirm the location of the parabolic reflector’s focus.