Product Review and Short Takes from QST Magazine January, 2005 Product Reviews: • An Antenna Tuner and Audio DSP Filter for Elecraft K2 and K2/100 Transceivers • Alinco DJ-C7T Pocket-sized VHF/UHF FM Transceiver Short Takes: • EasyLog5 Copyright © 2004 by the American Radio Relay League Inc. All rights reserved.
PRODUCT REVIEW An Antenna Tuner and Audio DSP Filter for Elecraft K2 and K2/100 Transceivers Reviewed by Larry Wolfgang, WR1B Senior Assistant Technical Editor When I built an Elecraft K2 and began to operate with that radio, I realized that this was no ordinary rig, kit or otherwise. The original Product Review radio included most of the options available at the time—KSB2 SSB adapter and the KNB2 noise blanker and the KBT2 internal gel-cell battery.
KAT100 control cable in parallel with an RS232 computer control cable, so both the tuner and the computer interface can be used at the same time. Alignment and Test After the construction is complete there are a few tests and alignment steps before you are ready to operate through the tuner. I was pleased to see all the proper LEDs light and the K2 main display acknowledge the tuner when I first connected the tuner and turned on the radio.
Table 1 Elecraft KAT100 Automatic Antenna Tuner Manufacturer’s Specifications Measured in ARRL Lab SWR range matched: Up to 10:1 typ (varies with band, smaller range on lowest bands). Tuning time: 1-5 seconds typical for initial tune-up, <1/2 second to recall stored settings. SWR display: 1.0:1 to 9.9:1 (on K2 LCD); 1:1 to 5:1 on 10 front panel LEDs. Current drain: 200-300 mA typical, 700 mA max. Enclosure size: 1.3 × 7.8 × 8.3 inches (HWD). Weight: 3 pounds (approx).
you don’t like the default settings for low and high frequency cutoff for the SSB filters, you can change those to suit your preferences. The RTTY filters also have adjustable center frequencies and bandwidths. I won’t describe the entire process of setting these filter parameters in this review. Suffice it to say that you will tap the DISPLAY button and then press and hold RCL a few times to reach the filtersetting menu. Then the BAND+ and BAND– buttons adjust the filter values up and down.
idea is that you can balance the system gain for the various types of signals. You can set the gain of the band-pass filters by mode. In addition you can set the SSB noise reduction gain as well as the CW noise reduction gain. Oh, And There is a Clock, Too! As if all this isn’t enough, the KDSP2 also includes a real time clock and calendar. The clock provides date and time readouts on the K2 display, and includes a lithium battery to keep the clock running even without connection to the supply.
duty handheld in areas where various VHF and UHF signals—not just amateur— proliferate. The receiver’s dynamic range hovers in the low 50 dB range in both ham bands. This level of performance does not offer a great deal of protection against infiltration from nearby in-band signals— or even signals in adjacent commercial bands, including Public Safety, paging systems and even broadcasters.
of the radio is for the charger or to connect an external supply of up to 6.5 V dc. audio not only crystal clear but very full and natural sounding. Getting Things Under Control Visiting Other Radio Worlds The gray front-panel pushbuttons bear clear, white legends for their primary functions—V/M (VFO/memory), SCAN, BAND, PWR and FUNC . These access major, secondary and, in some cases, tertiary functions, and the most important of these are spelled out in blue legends above each button.
By Steve Ford, WB8IMY EasyLog5 E asyLog5 is a complex piece of software. That is both a compliment and a caution. This is not merely a computerized ham log. EasyLog5 will control your radio (if your radio has computer-control capability), manage awards, allow you to send CW, send and receive PSK31 and PSK63, send pre-recorded audio (“voice keying”), monitor your favorite DX cluster and more. And when I say “more,” I really mean much more.
