QEX Subscription Order Card

American Radio Relay League Newington, Connecticut, U.S.A. 06111 U ARRL Member 6.00 Non-Member 12.00 in Canada, Mexico, and U.S. by First Class Mail U ARRL Member 11.00 Non-Member 17.00 Elsewhere by Airmail ARRL Member 21.00 U Non-Member 27.00 Remittance must be in U.S. funds and checks must be drawn on a bank in the U.S. Prices subject to change without notice. QEX, The ARRL Experimenter's Exchange is available at the rates shown at left Maximum term is 12 issues, and because of the...

Cheap Moonbounce

Many radio amateurs are interested in moon-bounce operation, but are precluded from participation because of real estate or budget restrictions. A communications method that uses computer power, rather than high power and high gain setups, may be just the ticket for such people. Of course, the laws of physics must be considered, and something must be sacrificed if power and antenna gain are lowered. That means bandwidth and the subsequent speed of communications. Host typical moonbounce QSOs...

Packet Radio With the Tono EXLE Communications Terminal

A complete stand alone VHF HF Packet, AMTOR, RTTY and CW terminal is accomplished by combining the Kantronics Packet TNC with the Tono EXL-5000E communications terminal. How is this done Steps one through nine can explain 1 Wire the RS-232-C cable supplied with the Kantronics unit as follows Brown and white wires should be connected to the individual phono-plug tips. Connect the shield and black wire together, then attach this to the previously wired phonoplug shields. The other wires are...

Assistance for Acssb Builders and Groups

After reading Bill Tynan's, W3XO, column in QST on ACSSB Jan 1985, p 63 , I was reminded about the previous Ham Radio paper Dec 1980, p 48 by James, Eagleson, WB6JNN. Somehow all of this seems familiar, like somebody reinventing the wheel Fifteen to eighteen years ago during the last years of AT amp T Long Lines HF radio circuits, they installed a Linkoplex system that was developed in England, A pilot carrier was always used for AFC, but this provided AGC and bandpass shaping as you described...

High Performance DTMF Decoder Simplifies Control of Remote Base Stations

Dtmf Remote Control Pic

17020 Snyder Rd., Chagrin Falls, OH 44022 The need for a compact, low power, and maintenance free DTMF decoder resulted in the design described here. It replaced an existing circuit which used several NE-567 decoders and required regular tweaking for satisfactory operation. The primary application was to control various functions of a VHP base station by using OTMF signals received on either the telephone line or an auxiliary receiver. To keep the circuit as small as possible, printed circuit...