On Wednesday 01 May 2019 22:02:01 Gene Heskett wrote: > On Wednesday 01 May 2019 21:09:11 bari wrote: > > There are some younger versions still around, we just don't like to > > brag :) > > Hang out a shingle then. Radio people are getting desperate.
And I should add that TBT, I have enough on my plate already. But its a job thats going begging. If I was out of pocket for more than 6 hours in the middle of the night, I'd have to hire a caretaker for my wife. Shes broken a hip and a leg in the last 2 years, hobbles with a walker 15 feet to a potty chair I have to dump and I do the food for both of us too. > > > Back in the early 80's I wrote antenna design software for microwave > > in Basic using Dos 2.1 on 8MHz PC's. It would take hours days to > > print out results on a dot matrix printer. I came across and old > > copy of it and it ran in seconds on a modern PC. Thats generally Chebyshev stuff. Most ATU's are some form of a pi network, not more than 5 or 7 poles as it has to be fairly broadband. I think the only butterworth I ever saw was in the directional array at KOTA-AM. Elmer Nelson, the designer of that was rather proud of the FCC mandated null point, we could drive across it and for about 20 feet it was gone. A kilowatt one mile away. Some sideband noise but not enough to tell what the song playing was. That null was 20 some db deeper than the commish specified. He also did some microwave filters, that combined with the 30 db of cross polarization, made it possible to do a two-way link from the middle of Agate Beds National Monument in western Nebraska to R.C.S.D., doing the program and commercial switching for KDUH-tv located about 30 miles east of the Monument. One 7GHz dish pointed each way, at the studios, the KOTA-tv transmitter site on Skyline Drive, a shack in the middle of nowhere called Hermosa SD, to a knob sticking out of Battle Mtn just north of Hot Springs SD, and 90 miles across the top of Pine Ridge back to the Monument, then east to the transmitter site. We had to shave the brush on Pine Ridge about every 4 or 5 years as it was well within the first fresnel zone. That Chebyshev stuff plays hell with group delay when its a 90 db brick wall cutoff 2 or 3 MHz from the edge of the channel, so Elmer designed a delay corrector that worked at the 70 MHz if of his receivers, getting rid of 99% of the edge breakups in the pix. Elmer was Tepco, but that was no connection to Tokio Electric( think Fukushima ). And that dominates a google lookup today It may still exist, but not Elmer unless he's made it well to north of 100 yo. Was in a metal building about 2 mi south of R.C.S.D. on highway 79 the last time I was there in '92 or '93. And Elmer looked in failing health then. As most anyone 90 yo does. I don't like mirrors anymore myself. He was the CE at KOTA at the time while I was a fresh 1st phone. 1960's. But Helen Duhamel ran us all off. She was difficult to please. Her son Bill, still thinks he can get a CE for 15k$ a year. I just chuckled and said offer 4x that if you want a real engineer and walked away. I'd go back for the right money except Rapid City is not the same place since the flood in 72. Now? No way. All the displaced people bought up all the accessible land all the way to Deerfield Lake, and put up no trespassing signs. Then they write letters to the editor because they are smashing up their cars running into the deer they won't let the hunters cross their 50 yard wide strip to harvest. There's a hundred square miles of those black hills that haven't had human footprints in the snow since the mid 70's. Buncha libtards. It was a hunting and fishing paradise before the flood. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
