Product Review and Short Takes from QST Magazine March 2009 Product Reviews: Analog HF/VHF wattmeters High end dual-lever keyer paddles Short Takes: RPC Electronics RTrack All-in-One APRS Tracker Copyright © 2009 by the American Radio Relay League Inc. All rights reserved.
product review QST Compares Analog HF/VHF Wattmeters Reviewed by Bob Allison, WB1GCM ARRL Test Engineer A standalone wattmeter is a “must have” in any Amateur Radio station and is the first piece of test equipment that many hams own. Whether you’re operating in your shack, car, boat or out in the field, your wattmeter shows you at a glance how much power your transmitter is putting out.
an RF sensing circuit disComet CMX-1 connects the battery when Frequency range 1.8-60 MHz the AWM-30 is not meaPower range 1-2000 W suring power. The ON/OFF Power requirement 11-15 V dc, 200 mA (lamps only) PEP measurement None switch controls only power Size (height, width, depth) 3 × 4.25 × 1.5" to the lamps. Price $170 The instruction sheet is four pages and includes a Actual Power (W) Indicated Power (W) schematic diagram. Out of Frequency (MHz) 2 14 28 50 the box, the AWM-30 didn’t 5 W CW 4.0 4.0 3.
and SWR with the power disconnected. I was surprised that it does not measure reflected power or display SWR in the PEP mode. Power accuracy is very good, though I did notice a jump up of a few watts when switching from AVG to PEP in the key-down CW test. The large 3.75 × 3.25 inch meter face is easy to read and provides good resolution with tick marks every 0.5 W up to 20 W (multiply by 10 or 100 for higher power ranges). A rear panel receptacle accepts 13.
can’t be switched off.) The PM2000A reads average power and SWR with the dc power disconnected. The accuracy of the meter tested was reasonable except for 1 kW peak power readings, which were quite high compared to the Lab equipment. The 4 page manual gives instructions for calibrating the PM2000A to match readings from a known power meter, and an easy screwdriver adjustment brought the errant readings into agreement. The PM2000A is equally at home in the shack or in the field.
Table 1 High End Dual Lever Paddle Summary Model Return, Bearings and Base Hardware and Contacts N2DAN Mercury Attracting magnetic return; Four race bearings; Chrome-plated steel base Dislodging Fingerpieces Pressure* Coarse threads, locknuts; 1.6 oz/ Long and heavy levers; 2.8 oz Flat rhodium-plated silver contacts Long flecked dark purple rounded plastic; 1.1 to 2" above operating surface Weight (lb) Price 3.
gerpiece height above the operating surface is identical to my original, ranging from 1.1 to 2 inches. Contacts for a cable to the keyer are recessed on the bottom of the paddle, with an exit hole in the back for the cord. I tied a knot for strain relief before soldering the wires to the three terminals. With one exception, everything about this Bencher Mercury exudes quality.
BEGALI SCULPTURE The Begali Sculpture has captured center stage as a state-of-the-art dual-lever paddle. The Sculpture is like an exceptionally fine musical instrument. It can be played by people at any skill level, but it’s no wonder that experts have snapped up this engineering and artistic masterpiece. Begali makes nine regular paddle models and three straightkeys, plus limited editions.
short takes RPC Electronics RTrak All-In-One APRS Tracker Larry Wolfgang, WR1B QEX Editor lwolfgang@arrl.org Many readers are familiar with the Automatic Packet/Position Reporting System (APRS), first developed by Bob Bruninga, WB4APR. Bob’s recent QST article describes the many ways we can use APRS.1 The RTrak unit is a complete APRS tracker package, but does not receive or decode APRS data.
