It's been a while since I looked at a Mitreck manual but IIRC there were 2 reed sockets on the mobile. Normally only one was populated and a jumper was installed to use the same reed for T/R. 2 reeds would allow cross coding as Skipp mentioned. Any Mitreck manual should have the PL board layouts (there were more than one), the DPL boards and as I recall the reedless PL board in the later manuals.
Milt N3LTQ ----- Original Message ----- From: "skipp025" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Saturday, May 26, 2007 12:57 AM Subject: [Repeater-Builder] Re: Repurposing Mitrek PL Board? > Re: Repurposing Mitrek PL Board? > > The typical mobile two-way radio including the Mitrek is a > half duplex operation. During receive the board decodes the > ctcss tone and provides a logic line output to turn on the > audio amplifier (speaker audio). > > Note at least one contact pin of the board interface plug is a > logic line function that changes state with transmit mode. The > board then changes over to tone encode mode during tx and spits > out the tx sub tone from that audio section of the board. > > There is only one tone reed or frequency select part on the stock > board so only one tone choice is used for transmit and receive. > > Moving along... when the board is populated with all the parts > you can receive decode one tone and transmit a different tone > when the board switches over to tx mode. We call it cross code > and it's very useful in some multi site systems. > > I haven't tried it with the Mitrek board but I do know the MSR-2000 > Repeater board will allow transmit and receive ctcss (tone) operation > at the same time (full duplex). Per my previous post the chips are > the same as the Mitrek board with different motorhead part numbers > (go figure). > > So there is a chance the fully populated Mitrek Board might allow > full duplex or at least cross code ctcss operation if the two > sections can be enabled at the same time. Sometimes that's allowed > as a normal option for various product but I don't believe the > Mitrek was ever offered up as a full duplex radio. I would not > expect the tone board to operate full duplex without some > modification. Just for the sake of fun trivia... your board also > fits the Motrek radio. > > Getting dizzy yet? > s. > >> Kris Kirby <[EMAIL PROTECTED]> wrote: >> So would this board be an encode-only board or decode-only? >> I fear encode only... >> Kris Kirby, KE4AHR <[EMAIL PROTECTED]> > >> >> On Fri, 25 May 2007, skipp025 wrote: >> > If the board is untouched (no parts removed) then it's possible >> > that board version has the capacity to cross-code tones when the >> > other missing parts are installed. > > > > > > > > Yahoo! Groups Links > > >
