Hi There are similar "protections" built into the TV station licensing process. In the case of TV it's a whole raft of issues that all boil down to how good the receiver needs to be. IMD, RF selectivity, IF selectivity, all figured in. I suspect there were other things I've forgotten about.
About every 10 years or so, the FCC used to sponsor a study done by one company or the other of how much things could be improved. Each and every study came to the conclusion that you could make a better TV and have more channels on the air. As far as I know, nothing ever changed as a result. They were interesting papers though. Frequency allocation and large scale receiver design have always gone hand in hand. It's been that way at least since WWII and likely before that as well. Bob -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Lester Veenstra Sent: Thursday, June 09, 2011 3:32 PM To: 'Discussion of precise time and frequency measurement'; [email protected] Subject: Re: [time-nuts] GPS interference and history... Actually Chuck it was intermod in the front end creating 10.7 directly. Lester B Veenstra MØYCM K1YCM [email protected] [email protected] [email protected] US Postal Address: PSC 45 Box 781 APO AE 09468 USA UK Postal Address: Dawn Cottage Norwood, Harrogate HG3 1SD, UK Telephones: Office: +44-(0)1423-846-385 Home: +44-(0)1943-880-963 Guam Cell: +1-671-788-5654 UK Cell: +44-(0)7716-298-224 Jamaica: +1-876-352-7504 This e-mail and any documents attached hereto contain confidential or privileged information. The information is intended to be for use only by the individual or entity to whom they are addressed. If you are not the intended recipient or the person responsible for delivering the e-mail to the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this e-mail or any documents attached hereto is prohibited. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Chuck Forsberg WA7KGX N2469R Sent: Thursday, June 09, 2011 8:17 PM To: [email protected]; Discussion of precise time and frequency measurement Subject: Re: [time-nuts] GPS interference and history... The image frequency for an FM receiver with a 10.7 mHz IF is 21.4 mHz above or below. Perhaps they were worried about receivers with IFs in the 5 mHz range? -- Chuck Forsberg WA7KGX N2469R [email protected] www.omen.com Developer of Industrial ZMODEM(Tm) for Embedded Applications Omen Technology Inc "The High Reliability Software" 10255 NW Old Cornelius Pass Portland OR 97231 503-614-0430 _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
