### CHANNEL FREQUENCY PROGRAMMING by TELINDEL and LEN160E Radiotelephones

( An answer to concrete question by CM6LAR, Lazaro, Cuba )

The TELINDEL (LEN160E) PLL oscillator generates the frequencies for receiver mixer and transmitter, that are equal. (Transmitter frequency is represent a PLL's frequency + 10.7 MHz). Channels are programmed by installing diodes in the Diode Matrix.

The Diode Matrix is a printed card board with vertical and horizontal tracks which on certain position are connected by diodes (aka diode-comb), or wire links (when one-channel version).

Horizontal rows are the common wire (cathodes) of the diode-combs. Their numeration (from 1 to 10) correspond to the channel number. The channel switch connected them to GND.

Vertical columns (letter symbol: A, B, C, D, E, F, G, H, I, K, L, M, N, P - writed in reverse order on board) are connected to the corresponding programming inputs of synthesizer S 187 - Siemens, or Bulgarian IC CM1630P : A2, A4, A8, A16, A32, A64 and B1, B2, B4, B8, B16, B32, B64, B128 .

Diode matrix allows programming up to 10 channel frequencies. Each channel frequencies is a result of its own division factor N.

N = ( f (channel, kHz) - 10700 ) /  12.5

Note: "N" is always a 5-digit even number for a frequency range 144-174 MHz and at channel spacing 25 kHz.

Programming of columns A2, A4, A8, A16, A32 and A64 is specified by the LAST TWO DIGITS of "N". The number consisting of these two digit is expressed as a sum of the numbers: 2, 4, 8 ,16, 32, 64 (binary coded form, BCD). At the same time they are also representing indexes of the corresponding A-columns. The number of the above-mentioned series that are used in composing a 2-digit are represented by "1"(High) and all remaining numbers of the same series that are not used by "0"(Low). The formed sequence of 1 and 0 specifies diodes'number and position in the matrix "comb" for columns A2....A64 where each column represented by 0 is connected through diode whose cathode is directed (by a common wire) to the row of the corresponding channel.

Programming of columns B1, B2, B4, B8, B16, B32, B64 and B128 is specified by the FIRST THREE DIGITS of "N". The number consisting of these three digits is expressed as a sum of some of the numbers: 1, 2, 4, 8, 16, 32, 64, 128 (binary coded form, BCD). At the same time they are also representing indexes of the corresponding B-columns. The numbers of the above mentioned series that are used in composing a 3-digit number are represented by "1"(High) and all remaining numbers of same series that are not used are represented by "0"(Low). The newly-formed sequence of 1 and 0 specifies the diodes'number and position in the matrix "comb" for columns B1....B128 where each column represented by 0 is connected through diode whose cathode is directed (by a common wire) to the row of the corresponding channel.

EXAMPLE:

Channel #1 = 144.675 MHz  = 144675 kHz :))

N = (144675 - 10700) / 12.5 = 10718

A = 18 ( 2+16 ) --> Programming columns A and D - free ( 1, high) & 4 ps.diodes( 0, low) for B, C, E, F

B = 107 ( 1+2+8+32+64 ) --> Columns G, H, K, M, N - free ( 1, high) & 3 ps.diodes( 0, low) for I, L, P

Note: In reverse order - from Right to Left! the diode-comb look thereby :
P,      N,   M,   L,   K,   I,   H,   G    /   F,     E,   D,   C,   B,   A    ( Are Letters on matrix board )
B128                                        B1  /  A64                            A2    ( Are corresponding Programm inputs of the synthesizer IC )

* Common wire of the comb (diode cathodes) is connected to corresponding Channel-row

lz1len / 04.11.2005 / eof

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