Hi. My hat is off to you for some really good detective work there. I'm not sure I would have had the ingenuity to figure out how to test that out. Very creative. 73, de Lou K2LKK At 10:16 AM 8/2/2007 -0500, you wrote: >Brett Winches writes: > > Does the drake have a hand held remote control like the 71 does? > > I don't know, but that turned out to be a real learning >experience for me in the mid eighties. > > At that time, I wanted to see if I could make an Apple >II computer control the ICR71 . I built a photo cell circuit >so as to be able to turn the IR flashes in to something the >Apple II could read. I then wrote a timing program in assembler >that counted processor cycles and waited for the infrared signal >to go off if it was on or on if it was off. it would store the >count in a table. > > I thought I had figured it out and even wrote a table of >values for each button press on the remote. > > I wrote another assembler program to toggle one of the >game paddle bits on and off in the Apple and fed that signal to >a driver feeding some infrared LED's I had scavenged from a >defunct TV remote. > > To make a long story short, it didn't work at all and I >was mystified. > > Then, I thought that there might be a carrier on those >data which was too fast for the 1-MHZ processor on the Apple to >follow. > > I remember taking that ICR71 receiver, connecting the >antena input through a capacitor to the collector of the photo >transistor and tuning around 100 KHZ while hitting buttons on >the remote. > > Sure enough, I heard bursts of carrier about every 33 >KHZ and I realized that IR remotes use a carrier and then gate >that on and off with lower-speed data. > > I couldn't make the Apple II get the timing right to do >the 33 KHZ carrier, so I built a 33-KHZ generator using a >crystal and some divide-by counters to get the frequency down to >33 kilohertz. > > When I ran the control program I had written on the >Apple and had it modulate that carrier, it did work. > > For a while, I had the Apple II set the R71 to 9.580 >megahertz every Sunday morning and turn on a cassette recorder >to get the Radio Australia DX program which they used to have.It >all actually worked pretty well after I learned how infrared >remotes work. > > Of course, each manufacturer has its own pulse code and >carrier frequency so each new remote is a new project. > >Martin McCormick WB5AGZ Stillwater, OK >Systems Engineer >OSU Information Technology Department Network Operations Group > > > >-- >No virus found in this incoming message. >Checked by AVG Free Edition. >Version: 7.5.476 / Virus Database: 269.11.2/933 - Release Date: 8/2/2007 >2:22 PM Louis Kim Kline A.R.S. K2LKK Home e-mail: [log in to unmask] Work e-mail: [log in to unmask] Work Telephone: (585) 697-5753