73 Amateur Radio Today – August 1979
Issue Contents:
You Can Watch Those Secret TV Channels
– a complete MDS receiving system …… K0JB K0FQA 32
Simple Dual-voltage Supply
– power for many projects …… W4VCZ 44
Bargain Zener Classifier
– Novice project …… WD8AAM 46
What the Hell is a Decibel?
– 1/10 of a bel of course …… WA5EBB 48
Frosting for the FT-901DM
– simple improvements for Yaesu’s superb performer …… K4TWJ 50
Mods for the Mark
– desirable extras for your Wilson HT …… K9EID 52
The History of Ham Radio
– part IX …… W9CI 56
Add-on Keyboard for Your Keyer
– the “a la carte” design …… K4BZD 60
Little Extras for the Century 21
– easy add-ons …… KN4JJG 64
The Many-talented 723
– how can regulated supplies get much simpler? …… WB0SKX 68
One-chip Tone Decoding
– how simple can it get? …… WB0VGI 72
Computerize That Mailing List
– club secretaries this is for you …… WB5UTJ/n5AUX 78
More Power to You
– 12-v supply has current limiting over-voltage protection the works …… K9MLD 90
Hit the Panic Button!
– a kill-switch system protects you and your ham shack …… AA6C 94
A Powerful Plus For Your TR-2200A
– improved supply/charger is a first-rate addition …… W6RON 96
Build a Wide-range Rf Resistance Bridge
– with a multitude of uses …… K4KI 100
Try the Potted J
– a 2m antenna impervious to the elements …… Staff 106
Testing the DSI 3600A Frequency Counter
– as much accuracy as you’ll ever need …… WA6ITF 108
The Tri-polarlzed VHC Antenna
– should be a killer for VHF …… K8UR 116
The One-Note Pipe Organ
– cw never sounded sweeter …… WB7CMZ 120
A Better Heathkit “Cantenna”
– improved metering circuit for an old standby …… W5ZG 124
The 80 Meter Coax L
– compact design really works …… AA4AG/dA1KV 126
73 Amateur Radio Today – August 1979
