>Involved with a group about to establish a combination of 1k2 and 9k6
>repeaters in my locale and would appreciate finding out about some 'simple'
>things others have uncovered by such an undertaking. Can anyone point to
>sites on the 'web' that may assist with things like power supplies, solar
>installation(s), bit-regernaration, state-machine DCD and the likes. Sorry
>for the twist of topic. TIA
Andrew,
I have built a 9600 baud bit-regenerating repeater. It operates on two
meters using modified Motorola Mitrek Radios.
The repeater consists of:
Transmitter: Motorola Mitrek 70w high band deck tuned @ 42 W
Receiver: Motorola Mitrek 70w high band deck tuned @ 42 W
Ringo Ranger II (ARX-2B)
TX/RX Duplexers (110 dB isolation) (6 cavitiy)
TAPR 9600 baud modem with bit regen and clock options
115Ah deep cycle 12V battery
6A battery charger
ALPHA DELTA lightning arrestor
70cm control link
Custom controller
I would recommend the Mitrek radios for this project. I used two radios
which were modified for 9600. One is setup as transmitter, and the other as
receiver. The beauty of this arrangement is that if one radio dies then the
crystals and cables can be swapped and the repeater lives on!
You should order two (2) TAPR 9600 modems with bit regen and clock option
now. You only need one for the repeater, but I found that the PLD's onboard
are quite sensitive and I blew them out a number of times while building
the repeater. This list may be handing if you burn up a modem:
http://www.deskmedia.com/~jjeffers/packet/spare-ics.html Also TAPR is in
the process of discontinuing the modem.
If you have a real desire to build your own modem then that should be
possible too. I have investigated a PIC microproccessor and a MX589 GMSK
modem chip for this application. Use my DCD detection code
(http://www.deskmedia.com/~jjeffers/packet/pic/) to determine when you have
signal, then make a FIFO in software.
http://www.redrok.com/electron.htm Provides some ideas for solar charge
controllers, as does http://www.homepower.com/ccgo.htm Home Power is our
big alternative energy magazine around here. You have download the entire
thing from the web (PDF) at http://www.homepower.com/
I have been playing with this stiff for a while - if you have any more
specific questions please feel free to ask me.
73's,
-James Jefferson KB0THN
[EMAIL PROTECTED]
http://www.deskmedia.com/~jjeffers/
