So in a nutshell, microwave is a band of precision and pinpoint accuracy? Common sense that people shouldnt use wood for anything outside that demands long-term stability. Not only do the elements cause warping, but also prone to termites, etc. Wow!
Thanks for all the good input! John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn ----- Original Message ----- From: DCFluX To: [email protected] Sent: Wednesday, May 12, 2010 9:43 AM Subject: Re: [Repeater-Builder] Just curious... Microwave frequencies Generally microwave is used for point to point communications such as intercity links for telephone and studio to transmitter links for television and radio stations. The power generated by the transmitter is fairly low in the 10-100mW range but the antenna gain of a dish is extremely high 30-40dB depending on frequency and size of the dish, making a 100mW transmitter have an ERP that is 100 - 1000W. With that being said it is probably not a good idea to hang around the appreture of the dish while one of these systems is running. These frequencies are a challange because of the water vapor and rain really like to absorb them and with antenna gain that high the beam width is extremely narrow. I have a 6ft cookie that is .8 degrees wide. Longest path I saw was 65 miles on 12 GHz, had 15 foot dishes on both ends. Normal towers have a tendency to twist depending on wind and temperature variations so its a good idea to mount the dishes with super thick poles directly into the ground with concrete. The local cable company put a system on 24 GHz that went 1 mile. worked great until it rained and got humid, they mounted the dishes on wooden phone poles and they twisted to the point where the link quit working. On Wed, May 12, 2010 at 9:32 AM, La Rue Communications <[email protected]> wrote: With that being said, how popular is the rest of the microwave band? Is it one of the more dangerous bands if used improperly? John Hymes La Rue Communications 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn ----- Original Message ----- From: DCFluX To: [email protected] Sent: Wednesday, May 12, 2010 9:27 AM Subject: Re: [Repeater-Builder] Just curious... Microwave frequencies No 800 band for hams, closest is 902-928 which is the 33cm ham band, it is also used by ISM type devices such as cordless phones, baby monitors, 802.11 internet and wireless video senders. 10 S. Aurora Street Stockton, CA 95202 http://tinyurl.com/2dtngmn
