Tetra-Mobile-Stations Detector
******************************

Restrictions of the demoversion
*******************************

- The demoversion is only available for the ICOM R10.

- The demoversion will run 4 hours until you need to 
  restart the TMS-Detector program. You have to quit 
  and to restart the program, if you want to continue.
  
- The demoversion will only log 20 messages. You have
  to quit and to restart the program, if you want to 
  continue.   

- Do not expect software updates for the demoversion.

- The demoversion do not need and can not use the TMS
  timing circuit. You can use the original ICOM R10 
  C-IV cable or any compatible cable to direct control 
  the R10 by the TMS-Detector program. The timeslot 
  sampling of the Tetra channels direct by the PC is 
  not as accurate as with the TMS timing circuit. 
  Therefore there is a higher probabillity to oversee 
  Tetra signals.



Schematic for a very simple ICOM-PC C-IV cable
**********************************************     

                                                     PC RS-232
            Gnd-----E
                      [BC547C] B---4.7kOhm------TX (Pin3, Sub-D-9)
                    C
                    |                  [1N4148]
                    |                  x--|<---RTS (Pin7, Sub-D-9)
                    |                  |
                    |                4.7kOhm
 3.5mm mono plug    |                  |
 to the ICOM R10    |                  x--------RX (Pin2, Sub-D-9)
                    |                  |
 C-IV bus (tip)     |                  C
 -------------------x--10---B [BC547C]
                      kOhm             E
                                       |
 --------------------------------------x-------Gnd (Pin5, Sub-D-9)
 Gnd              
            BC 547C                
           ---------  view on      
           \ C B E /  the leads    
             -----                                                    

Note: This circuit is very simple and does not provide a negative 
      voltage on the RX line. If you get problems with this circuit, 
      you probably have to build a level interface with a Maxim 232.
      


Maxim232 level interface (the correct C-IV interface solution)
**************************************************************

                    [1N4148]         [7805]
RTS (Pin7, Sub-D-9)--->|--x----x----Vin   Vout-x +5V
                          |    |(+)    GND     |
DTR (Pin4, Sub-D-9)--->|--x   470uF     |      |
                    [1N4148]   |        |      | (+)
                              Gnd      Gnd     x---47uF--Gnd
                                               |  
GND (Pin5, Sub-D-9)------Gnd                   |
                                               |
                                               |
                           [Max232]            |
                  x------1          /--16------x +5V
                  |(+)      (+)     |
                 10uF    2----10uF--^  15------x-----Gnd
                  |                            |
                  x------3             14      |
                                               |
                  x------4             13      |
                  |(+)                         |
                  x-10uF-5             12      |     Gnd    3.5mm mono plug 
             (+)                               x---------   to the ICOM R10 
        Gnd----10uF------6             11
                                                 C-IV bus (tip)
RX (Pin2, Sub-D-9)-------7             10--------x-------  
                                                 |         
TX (Pin3, Sub-D-9)-------8              9---|<---x
                                           BAT43      
         


What to do against to much computer noise?
******************************************

- Try to use an external antenna far away from any computers.
  Even five or ten meters away the noise level will be lower.

- Try to shorten some interferences with a 10pF condensator
  between Gnd and the C-IV line.
  
- Do you get fewer interferences, if you disconnect the R10
  from the AC/DC adaptor? Try the following EMI filter:
  
    DC Plug -x--1uH--x--1uH--x-- to DC/AC  
             |       |       |      adaptor
    R10     10pF    100pF   1nF
             |       |       |
    Gnd  ----x--1uH--x--1uH--x-- Gnd