We had 'PL' capability 35 years ago and were using it then. Neil - WA6KLA
Don Pomplun wrote: > > You say "NOT often found in amateur radios". My recollection of the > history is that way back when there was no PL capability; this was > followed by transmitting 100 Hz PL; then programmable PL xmit; and now > I see many more radios capable of PL encode AND decode. > Our situation is that we have small local workgroups who need to > converse locally, and occasionally chat with everybody in all groups. > If I thought about it, I could probably figure out a "best way" to > arrange this with simplex & separate T&R freqs, and different PLs. > However, it might be too complicated for the average user to deal > with. > 73, > Don > > At 09:00 PM 5/18/2005 -0700, you wrote: > > > Don, > > > > You're absolutely correct. I was using the term "simplex" in the > > sense > > of TX and RX on the same frequency. Although certainly not a > > universal > > definition, the term "half duplex" is often used to describe TX and > > RX > > on two different frequencies but not simultaneously. Some might > > consider that practice to be wasteful of spectrum. > > > > Perhaps a more efficient alternative is to configure the simplex > > repeater radio to use different CTCSS tones for TX and RX. The user > > radios must, of course, be capable of encoding and decoding > > different > > tones, but that capability is not often found in Amateur grade > > radios. > > > > 73, Eric Lemmon WB6FLY > > > > Don Pomplun wrote: > > > > > I agree that hearing everything twice would get old quickly. > > > What's wrong with this: The simplex repeater box listens on one > > freq, > > > then retransmits on another. Everybody hears each transmission > > only > > > once, albeit with a delay. > > > Isn't the main advantage that of avoided cost? > > > > > > > > > At 07:38 PM 5/18/2005 -0700, you wrote: > > > > > >> The Zetron 19B "Simplexor" was the only simplex repeater that > > seemed > > >> to > > >> work properly, since it was designed for public-safety > > application, > > >> primarily for forwarding 2-tone sequential paging signals > > followed > > >> by a > > >> voice message. The 19B could be set to repeat the tones and > > message > > >> a > > >> certain number of times. Best of all, it was designed to plug > > into > > >> most > > >> Motorola and Kenwood commercial radios, and the voice quality was > > >> excellent. I use the word "was" for a reason; the 19B Simplexor > > was > > >> > > >> discontinued a year or so ago. > > >> > > >> Not every radio user appreciates a simplex repeater, since all > > >> listeners > > >> hear every transmission twice. That gets old, really quick! > > >> > > >> 73, Eric Lemmon WB6FLY > > > > > > > > > > > > > > > > > > > > > > > > > > > > > --------------------------------------------------------------- > > > Yahoo! Groups Links > > > > > > * To visit your group on the web, go to: > > > http://groups.yahoo.com/group/Repeater-Builder/ > > > > > > * To unsubscribe from this group, send an email to: > > > [EMAIL PROTECTED] > > > > > > * Your use of Yahoo! Groups is subject to the Yahoo! Terms of > > > Service. > > > > > > > > > > > > > > > > > > > Yahoo! Groups Links > > > > > > > > > > --------------------------------------------------------------- > Yahoo! Groups Links > > * To visit your group on the web, go to: > http://groups.yahoo.com/group/Repeater-Builder/ > > * To unsubscribe from this group, send an email to: > [EMAIL PROTECTED] > > * Your use of Yahoo! Groups is subject to the Yahoo! Terms of > Service. Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Repeater-Builder/ <*> To unsubscribe from this group, send an email to: [EMAIL PROTECTED] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
