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Dear SPARC Members and Friends,

Thank you to everyone who attended last night’s in-person meeting of the South Pasadena Amateur Radio Club. We especially appreciate everyone who helped with setup and teardown of the tables and chairs before and after the meeting.

We were also very pleased to welcome several visitors:

• The White family: Garrett and Ryden
• The Sun family: Ashley, Crystal, Justin, and April

A special thank you goes to our members who made an extra effort to welcome our visitors and explain what we were doing in an accessible and engaging way for non hams. Kevin KB7JYF, Steve KN6ZOO, Mark WB6CIA, and Rick KI6ZKM all went out of their way to help make the evening enjoyable and educational for everyone.

Last night’s activities focused on our ongoing 6 meter project work and testing. Topics and demonstrations included:

• Discussion of the 6 meter antenna builds from the prior two meetings
• Review of the importance of testing standing wave ratio (SWR) before operating an antenna system
• Demonstration of the RigExpert 500 MHz Antenna Analyzer
• Testing of 6 meter simplex operation on 51.5 MHz
• Testing of 6 meter repeater operation through the Mt. Harvard repeater (53.62 MHz, -0.5 MHz offset, PL 107.2)

We also tested several newly-built 6 meter antennas for Colleen NR6M, Vince KF6FLJ, Efren KN6YYN, and John AC6VV. All antennas performed very well, with resonance near 51.0 MHz and SWR remaining under 3.0 through approximately 53.0 MHz.

In addition, we tested several 6 meter radios provided by Jeff W2JCL, Efren KN6YYN, and Stan KR6CV.

Our attempts to use the Mt. Harvard repeater were successful, although operation was somewhat hampered by desensitization. Because the repeater input and output frequencies differ by only 500 KHz, and our transmit and receive antennas were separated by only a few feet, local interference effects were significant during testing.

Finally, everyone is invited to join next Wednesday’s simplex net on May 13 at 7:30 PM. We will:

1. Begin on our usual 2 meter simplex frequency, 145.6 MHz
2. Switch to 6 meter simplex on 51.5 MHz
3. Then switch to the Mt. Harvard 6 meter repeater: 53.62 MHz, -0.5 MHz offset, PL 107.2

Please program and test the repeater settings in advance of the net if possible.

Thanks again to everyone who attended and contributed to another successful SPARC meeting.

73 de Jeff W2JCL

At our November meeting, SPARC members shared the antennas they use to get on the HF bands at home. Here are a selection of pictures and comments on each antenna.

Chameleon Emcomm II

The antenna is pointed northeast but is not very directional. It handles 200 watts on SSB, 100 watts on digital. Thanks to its 5 to 1 coil, the wire is resonant on 20, 40, 80. Using the antenna on 30 and 80 requires a tuner. The tripod was purchased on Amazon and spray-painted matte black to blend into the environment.

Comet CHA-250B vertical

The Comet is mounted on a pole attached to the garage on a hinged base so it can fold it down if conditions are windy. The antenna is self-contained, requiring no radials. It receives impressive DX like Brazil, Japan and Australia. However, it picks up a fair bit of noise too. A key advantage is its small, unobtrusive footprint.

MFJ Mobile Ham-tenna Whips

This is a pair of MFJ “HF Mobile Ham-tenna Whips” on a back-to-back bracket, forming a dipole configuration. The pairs of whips are tuned to a single band [10, 20, 40m] and do a good job. The bracket and whips are mounted on a fiberglass push-up mast with a tripod base. It provides the benefits of a dipole without requiring a support in, say, the neighbor’s tree. Tuning for a low SWR requires adjusting the whip length with an Allen wrench.

29’ random wire

In the box is a 9:1 UNUN that is meant for a “random” wire.  The antenna is designed not to be resonant on any particular ham frequency, and it requires an external tuner to provide acceptable SWR from 6 to 40 meters.  Build instructions are available in this PDF.

Although the instructions call for a random wire, it is necessary to avoid certain wire lengths so that the antenna is not accidentally resonant on any particular frequency. Here is a chart of safe wire lengths. 

NA4RR Hexbeam

The NA4RR Hexbeam covers 20m through 6m. The most difficult issue was getting it mounted on the mast. The second issue is aligning the antenna direction with the rotor control direction.

Cushcraft R7

This Cushcraft R7 is mounted at about 33 feet, covering the 10, 12, 15, 17, 20, 30, and 40-meter bands. The 40-meter band performs best. The 20-meter band has been somewhat limited, the 15-meter band challenging, and the 10-meter band works occasionally. Here are a few links for further reference:

• Cushcraft R7 Setup at VE3XYD QTH
• Cobweb vs. Cushcraft R7
• eHam Reviews of the Cushcraft R7
• Cushcraft R7 Antenna Assembly and Installation

Cushcraft A4S Yagi

This Yagi works on 10, 15, 20, and 40. It reaches essentially anywhere on earth, even the South Pole. The element lengths are 20 feet long, spaced 10 to 15 feet apart. It’s mounted on a Tri-Ex crank-up tower, requiring no guy wires, that nests down to 23 feet. The tower is just over 60 feet tall when fully deployed. There are rotators on both the tower and the Yagis on the chimney. 

Halloween Special Event Update

Our October 31 special event station W6H was a fun night of operating, even though our location didn’t have the best propagation. Here is a map of our contacts, and check out a few photos posted on our Instagram account.

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