MCX-90/MCX-100 PROM PROGRAMMING

Specifically in reference to the MCX-90, it is very similar to the MCX-100, with 16 channels instead of 32. The information below for the MCX-100 should also work for the MCX-90.


The VHF radio uses this programming directly. For UHF use, divide all
frequencies FIRST by three. Also, Syntor radios use this same programming
algorythm but have a different IF freq on rcv.


I . FREQ.  PROMS

Frequency PROMs will be programmed as follows:

 1. All locations in the PROM will be filled. Undefined channels will 
    be strapped to previous channels.

 2. "Blank" channels will exist on transmitter only and the PROM word will     
    contain all "F" hex on that transmitter channel.
    (the read order of the prom is byte 7,6,4,0,1,2 : 2&5 not read)

 3. Types of frequency PROMs will be:

    A.     Case 1 256 X 4 for  < 16 channels (N82S129)
    B.     Case 2 512 X 4 for  > 16 channels (N82S131)

      Original Field proms were MMI 5301-1J for 16 ch, and MMI 5306-1J
      for 32Ch.  Note: the R1800 field programmer software/firmware  
      was upgraded to use the Signetics N82S style proms.  Other proms,
      once programmed with the correct data (i.e. 74s288) don't use the
      same programming algorythms, and will be destroyed by the 
      programmer.

 4. Frequency information for the PROM fills eight consecutive locations
    in the PROM for each channel.

 5. Channel locations in the proms are as follows:


16 ch RF prom:

Addr  Ch   Addr  Ch    Addr  Ch
           50-57 R10   A8-AF T5
00-07 R16  58-5F R11   B0-B7 T6
08-0F R1   60-67 R12   B8-BF T7
10-17 R2   68-6F R13   C0-C7 T8
18-1F R3   70-77 R14   C8-CF T9
20-27 R4   78-7F R15   D0-D7 T10
28-2F R5   80-87 T16   D8-DF T11
30-37 R6   88-8F T1    E0-E7 T12
38-3F R7   90-97 T2    E8-EF T13
40-47 R8   98-9F T3    F0-F7 T14
48-4F R9   A0-A7 T4    F8-FF T15

32 channel RF prom:

Addr    Ch   Addr   Ch   Addr    Ch
000-007 R32  0B0-B7 T6   160-167 R28
008-00F R1   0B8-BF T7   168-16F R29
010-017 R2   0C0-C7 T8   170-177 R30
018-01F R3   0C8-CF T9   178-17F R31
020-027 R4   0D0-D7 T10  180-187 T16
028-02F R5   0D8-DF T11  188-18F T17
030-037 R6   0E0-E7 T12  190-197 T18
038-03F R7   0E8-EF T13  198-19F T19
040-047 R8   0F0-F7 T14  1A0-1A7 T20
048-04F R9   0F8-FF T15  1A8-1AF T21
050-057 R10  100-07 R16  1B0-1B7 T22
058-057 R11  108-0F R17  1B8-1BF T23
060-067 R12  110-17 R18  1C0-1C7 T24
068-06F R13  118-1F R19  1C8-1CF T25
070-077 R14  120-27 R20  1D0-1D7 T26
078-07F R15  128-2F R21  1D8-1DF T27
080-087 T32  130-37 R22  1E0-1E7 T28
088-08F T1   138-3F R23  1E8-1EF T29
090-097 T2   140-47 R24  1F0-1F7 T30
098-09F T3   148-4F R25  1F8-1FF T31
0A0-0A7 T4   150-57 R26
0A8-0AF T5   158-5F R27

6. The frequency band to be determined by the customer frequencies.

Range Table

Range I  136 < Fc  <  162 Mhz
Range II 146 < Fc  <  174 Mhz

7. The following steps will  be performed to generate the eight PROM
   words for each channel:

   A. Determine range from Table in 6.

   B. Subtract 21.4 Mhz from all Receiver freqs.

   C. Determine the reference freq.
         a. Divide frequency to synthesize by 5Khz
            If the result is an integer, then D0,D1 = 1 of word 7
         b. If the result is a real number, try dividing by 6.25 Khz.
            If the result isn't an integer, then the frequency cant 
            be synthesized. If it is an interger then D0=1,D1=0 of word 7

   D. Determine N
          N = Freq/REF freq (typical ref freq is .005 Mhz [5 Khz] 
              or .00625 Mhz [6.25 kcs]

   E. Calculate Integer NA,NB
      NB=INT(N/63)
      NA=N-(63*NB)
      NB=NB-NA
      IF NA=0; then NA=63; NB=NB-64

   F. Convert NA, NB to binary bits.
          32  16  8   4   2   1
      NA= A5  A4  A3  A2  A1  A0

          512  256  128   64   32   16   8    4    2   1
      NB = B9   B8   B7   B6   B5   B4   B3   B2   B1  B0

   G.  Construct PROM words 0,1,3,4 from the bits in NA & NB
       (note a * means this bit is inverted from the value you got above. 
       If it was a 1, enter 0 - if 0 then enter 1)
        A3  A2  A1  *A0 --> W0
        B1 *B0  A5   A4 --> W1
        B5  B4  B3   B2 --> W3
        B9  B8  B7   B6 --> W4

   H. Set PROM word 2 and 5 to 1111 ( F hex)

   I.   Determine PIN shift bit    S0             VCO1         VCO2
   Range 1 Synthesizer         D2 word 6       D2  word 7    D3 word 7
   Below 120.6 Mhz                 1               0            1
   120.6-126.6 Mhz                 1               1            1
   126.6-132.5 Mhz                 1               0            0
   132.5-138.4 Mhz                 1               1            0
   138.4-144.3 Mhz                 0               0            1
   144.3-150.2 Mhz                 0               1            1
   150.2-156.1 Mhz                 0               0            0
   Above 156.1 Mhz                 0               1            0

   Range 2 Synthesizer
   Below 130.6 Mhz                 1               0            1
   130.6-136.8 Mhz                 1               1            1
   136.8-143.0 Mhz                 1               0            0
   143.0-149.2 Mhz                 1               1            0
   149.2-155.4 Mhz                 0               0            1
   155.4-161.6 Mhz                 0               1            1
   161.6-167.8 Mhz                 0               0            0
   Above 167.8 Mhz                 0               1            0

   J. Dual front end bit
       Bit D3 of word 6 is 0 when FC < (fmax+fmin)/2
       A good way to remember this, is, the lower front end is selected with
       the bit being 0, and the high front end is selected with a 1. Try to 
       split the total freqs between the two front ends, if your spread is
       greater than 6 mhz.

   Assemble the front end bits:
      Word 6 = D3(front end bit),D2(S0),D1(1),D0(1) 
               ( D1 and D0 spare - set high)
      Word 7= D3(VCO2),D2(VCO1),D1,D0 
               (1,1 if 5 kc channel, or 0,1 if a 6.25kc channel)
               hence     VCO2,VCO1,1,1 - if a 5 kc channel
                         VCO2,VCO1,0,1 - if a 6.25kc channel

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