Featured in QST, AUGUST 2000
A portable communications center featuring a VHF/UHF, 50/35 watt transceiver (Kenwood TM-V7A)
Can also accommodate a Kenwood TM- G707 or TM-261 (same size chassis and Mounting Bracket)
A built-in 12.5 amp switching power supply runs off 120 VAC. Box can also be powered from external DC.
Enclosed 36 amp/hour, (2) 6 volt gel-cells, can power the unit at low (5 watts), intermediate (10 watts) or high power.
The gel-cells are charged when connected to line voltage and external DC. Four voltage LED's provide battery status.
A cooling fan with two speeds circulates air around hot components and exhausts at the rear.
A 4 inch, front mounted speaker, can be switched off. Two top mounted jacks are provided for headphones or audio out for packet operation.
Basic needs are stored in the top, such as pens, flashlight, spare fuses, adapters and the microphone.
"Boom Box" upgraded with a Dual Band Kenwood TM-V7A Transceiver
"Boom Box" upgraded with a Dual Band Kenwood TM-G707 Transceiver
Original Box with a Kenwood TM-261 Transceiver
Internals with Kenwood TM-261 Transceiver
Subchassis and Radio Bracket
Kenwood TM-V7A/G707 Transceiver
This is the PCV J-Pole antenna I use with the Boom Box. It is a larger version of the Bicycle Jurassic Duck featured at the bottom of my ARES home page. The PVC antenna sets up in about 10 minutes and is stored, broken down, in the back of my truck for emergency use. Unlike the bicycle antenna, which uses small CPVC plastic pipe, this version is built into an 8 foot length of 1/2 inch PVC pipe. Several sections of 1 1/4 inch PVC, reinforced with a wood center, act as a mast for the J-Pole and are screwed together. The feed line exits via a PVC tee at the base of the J-Pole and is sealed against the elements with RTV sealant. Just connect up a coax feedline to the pigtail at the tee fitting and you're in business. Overall height is about 22 feet. The tripod stand is bolted to a foldable 1/2 inch plywood base. For windy conditions, the mast can be guyed with synthetic lines and a couple of concrete blocks can be placed on the plywood base.
PVC J-Pole antenna broken down. Note wood supports that overlap threaded joints.
2009 update
Schematics and parts list is no longer being supplied due to others modifying and posting my design on their sites without my consent.
Questions? Comments? Contact WX2NJ
