Syntor-X Code Plug Layout (or "You don't need the Suitcase Programmer")
Thanks to Mike Blenderman, K7IC, for filling in many of the blank fields.

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Sample Programming Sheet  

A QBASIC Program to generate PROM data for the Low Band Syntor X contributed by Brian Ellsworth, KA1JY

Feedback from users

The Syntor-X code plug contains a generic standard 2816-type 2Kx8 EEPROM. The 2816 can be read and written using virtually any standard EPROM programmer.

Each mode is specified by 16 bytes, starting with mode 1 at address $0000. Thus, mode 1 is contained in addresses 0000 through 000F, mode 2 in addresses 0010-001F, etc. There are a total of 32 entries for up to 32 modes. The modes account for 512 bytes of the EEPROM. The second 512 byte block contains optional Operator Select Coded Squelch codes (MPL). The EEPROM address lines are hooked up to access only 1024 bytes of the total 2048 bytes so these two 512 byte blocks account for all the usable space in the code plug.

(H Nibble = D₇D₆D₅D₄ L Nibble=D₃D₂D₁D₀)

Byte	Nibble	Field	Function
0	H	M1M2M3M4	Channel Scan non-priority scan list
0	L	M5M6M7M8	Channel Scan non-priority scan list
1	H	M9M10M11M12	Channel Scan non-priority scan list
1	L	M13M14M15M16	Channel Scan non-priority scan list
2	H	M17M18M19M20	Channel Scan non-priority scan list
2	L	M21M22M23M24	Channel Scan non-priority scan list
3	H	M25M26M27M28	Channel Scan non-priority scan list
3	L	M29M30M31M32	Channel Scan non-priority scan list
4	H	XP7XP6XP5XP4	Transmit PL / DPL / Disable
4	L	XP3XP2XP1XP0	Transmit PL / DPL / Disable
5	H	XM0XS0XP13XP12	Transmit PL / DPL / Disable
5	L	XP11XP10XP9XP8	Transmit PL / DPL / Disable
6	H	RP7RP6RP5RP4	Receive PL / DPL / Disable
6	L	RP3RP2RP1RP0	Receive PL / DPL / Disable
7	H	RM0RS0RP13RP12	Receive PL / DPL / Disable
7	L	RP11RP10RP9RP8	Receive PL / DPL / Disable
8	H	T4T3T2T1	Time-out
8	L	T0X0CR0	Time-out, Power control, Ref. Freq.
9	H	ST1ST0TB0P24	Scan Control
9	L	P23P22P21P20	Scan Control
A	H	SS0SQ1SQ0P14	Scan Control and Squelch Control
A	L	P13P12P11P10	Scan Control and Squelch Control
B	H	V1V0C1C0	Tx synthesizer program address 6
B	L	V1V0C1C0	Rx synthesizer program address 6
C	H	B9B8B7B6	Tx synthesizer program address 4
C	L	B9B8B7B6	Rx synthesizer program address 4
D	H	B5B4B3B2	Tx synthesizer program address 3
D	L	B5B4B3B2	Rx synthesizer program address 3
E	H	B1B0A5A4	Tx synthesizer program address 1
E	L	B1B0A5A4	Rx synthesizer program address 1
F	H	A3A2A1A0	Tx synthesizer program address 0
F	L	A3A2A1A0	Rx synthesizer program address

Bytes 0, 1, 2, 3 - Channel Scan non-priority internal list. Any bit set to a zero will include the corresponding mode in the non-priority scan list. 0xFFFFFFFF is an empty non-priority scan list.

	Byte 0:	Byte 1:	Byte 2:	Byte 3:
D7	- mode 1	- mode 9	- mode 17	- mode 25
D6	- mode 2	- mode 10	- mode 18	- mode 26
D5	- mode 3	- mode 11	- mode 19	- mode 27
D4	- mode 4	- mode 12	- mode 20	- mode 28
D3	- mode 5	- mode 13	- mode 21	- mode 29
D2	- mode 6	- mode 14	- mode 22	- mode 30
D1	- mode 7	- mode 15	- mode 23	- mode 31
D0	- mode 8	- mode 16	- mode 24	- mode 32

 

• When Selectable Scan is enabled the radio will not use the above scan list. Fixed Scan must be enabled to use this scan list (see Byte A details).

Bytes 4, 5 - Tx PL / DPL / Disable codes. 0xFFDF is PL/DPL Disabled with no MPL Select (0x00C0 also works).

• NOR - Normal DPL codes.
• INV - Inverted DPL codes (this is a result of the DPL signal inversion, not a logical bit inversion).
• All 9 bit values are logically inverted. i.e. DPL 023 would be stored as 754, or 047 would be 730.
• There are 84 standard DPL codes.
• DPL codes are exactly the same format for Tx and Rx. Use this table for Rx DPL also.

• All 14 P₁₃ - P₀ bit values are logically inverted and are shown above as logically inverted values with control bits.
• PL Code = format (control bits + logical invert ( convert to integer ( PL Frequency * 18.0616)))
• Formatting involves swapping the 2 bytes of the 16 bit integer result.

Byte 4:

D7 - PL P7 , DPL I0		I = 0 - DPL NOR normal signal	I = 1 - DPL INV inverted signal
D6 - PL P6 , DPL C0		DPL format ABC = DPL code (3 octal bytes for 9 bits total, logically inverted values). PL format P = PL code (14 bits, logically inverted values).
D5 - PL P5 , DPL C1
D4 - PL P4 , DPL C2
D3 - PL P3 , DPL B0
D2 - PL P2 , DPL B1
D1 - PL P1 , DPL B2
D0 - PL P0 , DPL A0

Byte 5:

D7 - MPL Select M0		M = 0 - MPL Operator Select	M = 1 - No MPL Operator Select
D6 - PL/DPL Select S0		S = 0 - PL code	S = 1 - DPL code
D5 - PL P13 , DPL E0		E = 0 - DPL disable	E = 1 - DPL enable
D4 - PL P12 , DPL A1
D3 - PL P11 , DPL A2
D2 - PL P10 , DPL always = 1
D1 - PL P9 , DPL always = 1
D0 - PL P8 , DPL always = 1

• The Yaesu VX-5R handheld does not like D_2-0 to be all-ones. Several Motorola-generated code plugs have contained other values. See http://kb8zqz.net/syntorx/#dplcoding for additional information and empirically determined bit patterns.
• All PL (P₁₃ - P₀) and DPL (A₂-A₀, B₂-B₀, C₂-C₀) bit values are logically inverted in bytes 4 and 5.
• All of the bits in bytes 4 and 5 have a dual function depending on PL or DPL selection, except for byte 5 - D₇ and D₆.
• The MPL Operator Select causes the radio to address the external System 90*s "Operator Selectable PL/DPL Encode" board (TRN4322A or TRN4324A). If the M8 line is pulled low by the board the radio will use M1-M6 to get the address of the Tx PL/DPL information from the board.

Bytes 6, 7 - Rx PL / DPL / Disable codes. 0xFFDF is PL/DPL Disabled with no MPL Select (0x00C0 also works).

• All 14 P₁₃ - P₀ bit values are logically inverted and are shown above as logically inverted values with control bits.
• PL Code = format (control bits + logical invert ( convert to integer ( PL Frequency * 61.17)))
• Formatting involves swapping the 2 bytes of the 16 bit integer result.

Byte 6:

D7 - PL P7 , DPL I0		I = 0 - DPL NOR normal signal	I = 1 - DPL INV inverted signal
D6 - PL P6 , DPL C0		DPL format ABC = DPL code (3 octal bytes for 9 bits total, logically inverted values). PL format P = PL code (14 bits, logically inverted values).
D5 - PL P5 , DPL C1
D4 - PL P4 , DPL C2
D3 - PL P3 , DPL B0
D2 - PL P2 , DPL B1
D1 - PL P1 , DPL B2
D0 - PL P0 , DPL A0

Byte 7:

D7 - MPL Select M0		M = 0 - MPL Operator Select	M = 1 - No MPL Operator Select
D6 - PL/DPL Select S0		S = 0 - PL code	S = 1 - DPL code
D5 - PL P13 , DPL E0		E = 0 - DPL disable	E = 1 - DPL enable
D4 - PL P12 , DPL A1
D3 - PL P11 , DPL A2
D2 - PL P10 , DPL always = 1
D1 - PL P9 , DPL always = 1
D0 - PL P8 , DPL always = 1

 

• All PL (P₁₃ - P₀) and DPL (A₂-A₀, B₂-B₀, C₂-C₀) bit values are logically inverted in bytes 6 and 7.
• All of the bits in bytes 6 and 7 have a dual function depending on PL or DPL selection, except for byte 7 - D₇ and D₆.
• The MPL Operator Select causes the radio to address the external System 90*s "Operator Selectable PL/DPL Decode" board (TRN4322A or TRN4324A). If the M8 line is pulled low by the board the radio will use M1-M6 to get the address of the Rx PL/DPL information from the board.

Byte 8 - Tx Time-Out T₄ - T₀, PA Power Control X₀ and Synthesizer Reference Frequency R₁ - R₀.

Tx Timeout Codes (T4-T0)
00000 - 7 min. 45 sec,	01000 - 5 min. 45 sec,	10000 - 3 min. 45 sec,	11000 - 1 min. 45 sec,
00001 - 7 min. 30 sec.	01001 - 5 min. 30 sec.	10001 - 3 min. 30 sec.	11001 - 1 min. 30 sec.
00010 - 7 min. 15 sec.	01010 - 5 min. 15 sec.	10010 - 3 min. 15 sec.	11010 - 1 min. 15 sec.
00011 - 7 min.	01011 - 5 min.	10011 - 3 min.	11011 - 1 min.
00100 - 6 min. 45 sec,	01100 - 4 min. 45 sec,	10100 - 2 min. 45 sec,	11100 - 45 sec,
00101 - 6 min. 30 sec.	01101 - 4 min. 30 sec.	10101 - 2 min. 30 sec.	11101 - 30 sec.
00110 - 6 min. 15 sec.	01110 - 4 min. 15 sec.	10110 - 2 min. 15 sec.	11110 - 15 sec.
00111 - 6 min.	01111 - 4 min.	10111 - 2 min.	11111 - Infinite

Byte 8:

D7 - Tx Time-Out T4
D6 - Tx Time-Out T3
D5 - Tx Time-Out T2
D4 - Tx Time-Out T1
D3 - Tx Time-Out T0
D2 - Tx Power Control X0		X = 0 - Low PA Power	X = 1 - High PA Power
D1 - Reference Frequency Selection R1		R = 00 - 6.25 KHz	R = 10 - 4.1667 KHz
D0 - Reference Frequency Selection R0		R = 01 - Not Used	R = 11 - 5 KHz

 

• The Tx time-out timer programs in 15 second intervals.
• The Tx Power Control bit is only used by some T53 and T83 model VHF radios. If it is installed, there is a separate PA power control adjustment for the low power setting on the common circuits board. The Motorola manual 68P81060E05-O, SYNTOR X High Band Systems Radio 150-174 MHz is the only one I am aware of that covers the T53 and T83 radios. The 68P81060E05-C, -B or -A manuals only cover the T43 and T73 SYNTOR X radios, 136-174 MHz. If a T53 or T83 radio will not put out full RF power, check the common circuits board and the Tx Power Control bit.
• The divider chip U602 contains the reference divider for the 14.4 MHz reference oscillator. The 4.1667 KHz reference generated with a 3456 divisor and is not normally used. The 5 KHz and 6.25 KHz reference frequencies are generated with 2880 and 2304 divisors, respectively. The Motorola manuals document the reference frequency divider codes sent to divider chip U602, not the codes (above) stored in the EEPROM.

Byte 9 - Scan Type ST₁ - ST₀, Talkback Scan TB₀, and Priority 2 Scan Mode P2₄ - P2₀.

Byte 9:

D7 - Scan Type ST1		ST = 00 - Double Priority Scan	ST = 10 - No Scan
D6 - Scan Type ST0		ST = 01 - Single Priority Scan	ST = 11 - Non-Priority Scan
D5 - Talkback Scan TB0		TB = 0 - Enabled	TB = 1 - Disabled
D4 - Priority 2 Scan Mode P24
D3 - Priority 2 Scan Mode P23
D2 - Priority 2 Scan Mode P22		P2 = 00000 - Secondary Priority Mode 1
D1 - Priority 2 Scan Mode P21		P2 = 11111 - Secondary Priority Mode 32
D0 - Priority 2 Scan Mode P20

 

• Double Priority Scan will scan primary priority mode P1 (byte A below), secondary priority mode P2 and any selected non-priority scan modes. Single Priority Scan will scan primary priority mode P1 and any selected non-priority scan modes. Non-Priority Scan will scan any selected non-priority scan modes. No Scan will disable scanning for this mode. In addition to programming the scan in the EEPROM the radio's J1 interface cable Channel Scan Enable line must also be grounded to enable any scanning.
• When System 90*s options have a "PRI" button the Operator can enable scanning or disable scanning with this switch (The radio's J1 interface cable Channel Scan Enable line is connected to the System 90*s "PRI" button). When there is no "PRI" button and scanning is desired, the radio's Personality Board Scan Enable Jumper JU1 is installed grounding the J1 interface cable Channel Scan Enable line. When using JU1, enabling scanning is not operator selectable and can not be disabled because JU1 is inside the radio and is not operator accessible.
• Many of the Syntor X System 90*s accessory optional control heads are unique to the Syntor X and will not work with other radios. The Syntor X can use some of the control heads from older Motorola radio lines. The development of System 9000 control heads appears to have obsoleted the Syntor X control heads before any other radios were designed to use them.
• Talkback causes an active channel that is being scanned to temporarily become the Tx mode when the PTT is pressed. If it is disabled pressing the PTT will transmit on the mode selected by the control head mode selector.

Byte A - Non-priority Scan Source SS₀, Squelch Type SQ₁ - SQ₀, and Priority 1 Scan Mode P1₄ - P1₀.

Byte A:

D7 - Non-priority Scan Source SS0		SS = 0 - Selectable Scan	SS = 1 - Fixed Scan
D6 - Squelch Type SQ1		SQ = 00 - AND/OR	SQ = 10 - not used
D5 - Squelch Type SQ0		SQ = 01 - AND/STD	SQ = 11 - STD/STD
D4 - Priority 1 Scan Mode P14
D3 - Priority 1 Scan Mode P13
D2 - Priority 1 Scan Mode P12		P1 = 00000 - Primary Priority Mode 1
D1 - Priority 1 Scan Mode P11		P1= 11111 - Primary Priority Mode 32
D0 - Priority 1 Scan Mode P10

 

• When Selectable Scan is enabled, the radio will only use optional System 90*s HLN4290A or TRN4326A Operator Select Channel Scan boards (up to 4 boards for a total of 32 modes) to select individual non-priority scan modes. When Fixed Scan is enabled, the radio will only use the programmed non-priority mode list in bytes 0 through 3 to select individual non-priority scan modes.
• The squelch type bit codes are: STD/STD, the receiver will unmute when the correct PL tone is detected, and will mute when the PL tone is not present. In the AND/STD case, the receiver will unmute when both correct PL tone is present AND the signal strength exceeds the squelch threshold; the receiver will mute when PL tone is not present. In the AND/OR case, the receiver will unmute when both correct PL tone is present AND the signal strength exceeds the squelch threshold; the receiver will mute when either PL tone is not present OR signal strength drops below the squelch threshold. The AND/STD setting is not used in the factory Rx PL/DPL programming. For Rx PL/DPL STD/STD guarantees the best received signal sensitivity. The Rx PL/DPL AND/OR programming is used as the factory AND squelch programming. The AND/STD setting is sometimes used in the factory programming when the Rx squelch is disabled (i.e. carrier squelch).
• The microphone hang-up box will disable the Rx PL./DPL when the microphone is "off the hook", regardless of the squelch type setting so the squelch threshold will determine if the receiver is muted or unmuted.

Byte B - Rx and Tx VCO range control, 3/4 variable modulus prescaler control and receiver extender control.

Byte B:

D7 - Tx Synthesizer V1
D6 - Tx Synthesizer V0		Tx V0 not used (800 MHz conventional radios only)
D5 - Tx Synthesizer C1		Tx C1 = 1 (low band radios only)
D4 - Tx Synthesizer C0		Tx C0 = 1 (low band radios only)
D3 - Rx Synthesizer V1		Rx V1 = 0 (800 MHz conventional radios only)
D2 - Rx Synthesizer V0		Rx V0 not used (800 MHz conventional radios only)
D1 - Rx Synthesizer C1		Rx C1 = 1 (low band radios only)
D0 - Rx Synthesizer C0		Rx C0 = 0 - Extender On	C0 = 1 - Extender Off (low band radios only)

 

• The divider chip U602 contains three dividers. They are the reference divider R (R₁ - R₀ see byte 8 above), the modulus 64 A divider (A₅ - A₀) and the modulus 63 B divider (B₉ - B₀). The external prescaler U601 programming bits C₁ and C₀ , phase detector U603 frequency change control bits S₁ and S₀ and the VCO frequency range control bits V₁ and V₀. All of this information is stored inside of U602 in six, four bit wide registers with 24 bits storage total (6 bits for A, 10 for B, 2 for R, 2 for V, 2 for C and 2 for S). The C, S, and V bits are brought out to external pins on U602 as C₁ pin 16, C₀ pin 15, S₁ pin 18, S₀ pin 17, V₁ pin 20 and V₀ pin 19. The two S bits are the only ones not programmed from the EEPROM. Every time the VCO frequency is changed (mode change, scanning or transmitting) U602 must be reprogrammed. So even though the Rx and Tx synthesizer codes are both saved in the EEPROM, only one of them at a time is loaded into the synthesizer via U602. Because there is only one reference divider R per mode in the EEPROM, both Rx and Tx must have the same reference frequency. If you really need to, the Syntor X 9000 can use different Rx and Tx reference frequencies in the same mode.
• The V₁ and V₀ bits control the VCO frequency ranges. The function of these bits is determined by the radio’s hardware design. The 800 MHz conventional radio V₀ is not connected and V₁ shifts the Tx VCO frequency up to the Rx frequency range for Talkaround (only on conventional radios). Because the 800 MHz radio VCO frequency doubler also doubles the range of the VCO, it does not need to have any incremental ranges. The VHF and UHF radios use the V₀ bit to shift the VCO approximately 53 MHz when changing from Rx to Tx and V₁ to make incremental shifts. The low band radio uses the V₁ and V₀ bits to make incremental shifts only.
• The C₁ and C₀ bits control the variable 3/4 modulus prescaler U601. The low band radio does not use this variable modulus prescaler so Rx bit C₀ is used to control the receiver extender instead (the low band U602 pin 16 is not connected, pin 15 only applies to the receiver extender circuitry and U601 is missing entirely). Even though the low band radio’s U602 pin 16 (C₁) is not connected, the RX C₁ bit is still used by the radio’s microprocessor and must be set to a 1 in order for the radio to function correctly.

 

• The factory Low Band radio frequency range is Tx & Rx 33 - 50 MHz.
• Rx IF is 75.7 MHz High Side Injection - Tx Injection = 172.8 MHz High Side

 

• The factory VHF Range 1 radio frequency range is Tx & Rx 136 - 154.4 MHz.
• Rx IF is 53.9 High Side Injection - Tx = VCO frequency

 

• The VHF Range 1.5 is a HAM band extension of a retuned VHF range 2 radio. The actual ranges above are determined by the retuning of the radio.
• Rx IF is 53.9 High Side Injection - Tx = VCO frequency

 

• The factory VHF Range 2 frequency range is Tx & Rx 150 - 174.
• Rx IF is 53.9 High Side Injection - Tx = VCO frequency

 

• The factory UHF Range 1 radio frequency range is Tx & Rx 406 - 420 MHz.
• Rx IF is 53.9 High Side Injection - Tx = VCO frequency

 

• The UHF Range 1.5 is a HAM band extension of a retuned UHF range 2 radio. The actual ranges above are determined by the retuning of the radio.
• Rx IF is 53.9 MHz Low Side Injection - Tx = VCO frequency

 

• The factory UHF Range 2 radio frequency range is Tx & Rx 450 - 470 MHz.
• Rx IF is 53.9 MHz Low Side Injection - Tx = VCO frequency

 

• The factory UHF Range 3 radio frequency range is Tx & Rx 470 - 488 MHz.
• Rx IF is 53.9 MHz Low Side Injection - Tx = VCO frequency

 

• The factory UHF Range 4 radio frequency range is Tx & Rx 482 - 500 MHz.
• Rx IF is 53.9 MHz Low Side Injection - Tx = VCO frequency

 

• The factory UHF Range 5 radio frequency range is Tx & Rx 494 - 512 MHz.
• Rx IF is 53.9 MHz Low Side Injection - Tx = VCO frequency

 

• The factory 800 MHz frequency range is Tx 806 - 825 MHz, Rx 851-870 and Talkaround Tx 851-870.
• Rx IF is 53.9 MHz Low Side Injection - Tx = VCO frequency * 2

 

• In reality most radios can exceed their original factory frequency spread rating. Many range 2 VHF radios (24 MHz spread) will stretch down to 144 MHz (30 MHz spread), even without retuning.
• A low range vs. a high range is an incremental step from one frequency range to the next higher or lower frequency range. A band shift or changing VCOs is a large frequency change (usually around 53.9 MHz).
• The VHF and UHF radios have models with different frequency coverage ranges. Because individual VHF and UHF radios can not cover an entire band, Motorola created different model radios that cover individual band segments (i.e. radio ranges). These ranges are numbered (i.e. Range 1, Range 2, etc.) and should not be confused with the incremental low and high VCO ranges (i.e. a VHF range 2 radio also has low and high VCO ranges). Remember, a radio range and a VCO range are not the same thing.

Byte C - Rx and Tx 63 modulus B divider data.

Byte C:
D₇ - Tx Synthesizer B₉
D₆ - Tx Synthesizer B₈
D₅ - Tx Synthesizer B₇
D₄ - Tx Synthesizer B₆
D₃ - Rx Synthesizer B₉
D₂ - Rx Synthesizer B₈
D₁ - Rx Synthesizer B₇
D₀ - Rx Synthesizer B₆

Byte D - Rx and Tx 63 modulus B divider data.

Byte D:
D₇ - Tx Synthesizer B₅
D₆ - Tx Synthesizer B₄
D₅ - Tx Synthesizer B₃
D₄ - Tx Synthesizer B₂
D₃ - Rx Synthesizer B₅
D₂ - Rx Synthesizer B₄
D₁ - Rx Synthesizer B₃
D₀ - Rx Synthesizer B₂

Byte E - Rx and Tx 63 modulus B divider data and 64 modulus A divider data.

Byte E:
D₇ - Tx Synthesizer B₁
D₆ - Tx Synthesizer B₀
D₅ - Tx Synthesizer A₅
D₄ - Tx Synthesizer A₄
D₃ - Rx Synthesizer B₁
D₂ - Rx Synthesizer B₀
D₁ - Rx Synthesizer A₅
D₀ - Rx Synthesizer A₄

Byte F - Rx and Tx 64 modulus A divider data.

Byte F:
D₇ - Tx Synthesizer A₃
D₆ - Tx Synthesizer A₂
D₅ - Tx Synthesizer A₁
D₄ - Tx Synthesizer A₀
D₃ - Rx Synthesizer A₃
D₂ - Rx Synthesizer A₂
D₁ - Rx Synthesizer A₁
D₀ - Rx Synthesizer A₀

• The synthesizer code (A, B, C and R) can digitally program any Voltage Controlled Oscillator (VCO) frequency for any Syntor X radio (low band, VHF, UHF or 800 MHz). In fact, even with the V₁ and V₀ VCO frequency range control bits, an individual Syntor X VCO can only cover a very tiny part of this total frequency range. The problem is the VCO and other components of the radio can not keep up with all the possible frequency codes. A DC steering voltage with a finite range is used by the Phase Locked Loop (PLL) to control the VCO frequency (i.e. the synthesizer code A, B, C and R programs a frequency, the V₁ and V₀ bits select a VCO range that matches that programmed frequency, and the steering voltage via the PLL locks the VCO on frequency). The VCO range selected by V₁ and V₀ is supposed to keep the VCO steering voltage within its finite range. If the DC steering voltage is not kept within its finite range the synthesizer may not work reliably or work at all (i.e. not locking on some frequencies when it is hot or cold etc.). The actual VCO frequency ranges are determined by the design, hardware and tuning of the VCO (these VCO ranges are sometimes referred to as PIN settings). If the PLL can not steer the VCO to the programmed frequency the PLL unlock Light Emitting Diode (LED) will light up. If the radio is in good working condition and the VCO will not lock, it is because of a synthesizer programming error, the frequency is outside the range of what the radio is physically capable of or the VCO microstrip trimming capacitors need adjustment. Adjusting the VCO microstrip trimming capacitors is only ever necessary to move the frequency coverage of some radios and it may require using different V₁ - V₀ VCO frequency ranges than the original factory settings.

• C_(value) is used in the frequency calculations, however, the corresponding C₁ and C₀ values are used to program the synthesizer.
• Here is how to convert a frequency into a synthesizer code (all frequency calculations are in Hz):
• f_(vco) is determined by the desired Tx frequency, or the Rx frequency plus the IF frequency for high side injection or the Rx frequency minus the IF frequency for low side injection. The exceptions are the 800 MHz and low band radios. In the 800 MHz case, all programmed VCO frequencies are doubled, so after you determine f_(vco) (as described above) simply cut it in half. In the low band Tx case, subtract the desired Tx frequency from the Tx injection frequency and make it the f_(vco) frequency. The low band Rx programs normally using the low band IF frequency (see above).
• The Syntor X can only program frequencies that are a multiple of the reference frequency (i.e. 145.005 MHz is a valid frequency because it is a multiple of 5 KHz - and 145.007 MHz is not a valid frequency because it is not a multiple of any valid reference frequency - and 145.050 MHz is a valid frequency that is a multiple of either the 5 KHz or 6.25 KHz reference frequencies).
• Make sure that f_(vco) can be divided by at least one of the reference frequencies without any remainder. Use that reference frequency for f_(ref).
• f_(ref) is the reference frequency (in Hz) selected by R from byte 8 above.
• N = f_(vco) / f_(ref) (if N has a decimal remainder check f_(vco) and f_(ref) for errors)
• C_(value) = N modulus 3
• Use C_(value) to lookup C₁ and C₀
• For all radios except low band radios:
• N₍₁₎ = N / 3 (integer result only, throw away any decimal remainder)
• If C_(value) equals 0 then subtract 1 from N_(I)
• A = N₍₁₎ modulus 63
• If A equals 0 then set A = 63 and subtract 63 from N₍₁₎
• N₍₂₎ = N₍₁₎ / 63 (integer result only, throw away any decimal remainder)
• B = N₍₂₎ - A
• Convert A, B, C₁ and C₀ into binary and format them into the above synthesizer code bytes
• Set the R₁ and R₀ bits to match f_(ref) (a mode’s Rx and Tx must share the same reference frequency)
• Pick out a suitable V₁ and V₀ code to Finnish
• The VHF RSS prefers the 5 KHz reference frequency. All other radios prefer the 6.25 KHz frequency.

• The C₁ and C₀ values must be converted to a corresponding C_(table) value so the frequency can be calculated.
• Here is how to convert a synthesizer code into a frequency (all frequency calculations are in Hz):
• The frequency reference R₁ and R₀ bits must be decoded into an f_(ref) reference frequency in Hz.
• The V₁ and V₀ codes are only used by the VCO hardware and are irrelevant to this calculation.
• A, B, C₁ and C₀ must be separated from the Rx or Tx synthesizer code bytes.
• Use C₁ and C₀ to lookup C_(table)
• A and B must be converted from binary to base 10.
• It may not be possible to tell which radio the synthesizer code is from (many VCO frequencies overlap).
• For all radios, except 800 MHz and low band radios, use the following formulas (enter all frequencies in Hz):
• f_(vco) = ((((64 * A) + (63 * B)) * 3 ) + C_(table)) * f_(ref)
• f_(Rx) = f_(vco) + 53.9 MHz low side injection OR f_(Rx) = f_(vco) - 53.9 MHz high side injection
• f_(Tx) = f_(vco)
• For low band radios use the following formulas (enter all frequencies in Hz):
• f_(vco) = ((64 * A) + (63 * B)) * f_(ref)
• f_(Rx) = f_(vco) - 75.7 MHz
• f_(Tx) = 172.8 MHz - f_{(low band vco)}
• For 800 MHz radios use the following formulas (enter all frequencies in Hz):
• f_(vco) = ((((64 * A) + (63 * B)) * 3 ) + C_(table)) * f_(ref)
• f_(Rx) = (f_(vco) * 2) + 53.9 MHz
• f_(Tx) = f_(vco) * 2
• The f_(vco) frequency can be used to look up and confirm the V₁ and V₀ codes are correct.
• f_(vco) is the actual VCO frequency
• f_(Rx) is the actual receive frequency.
• f_(Tx) is the actual transmit frequency.
• The above formulas have been effective, but, not all VCO frequencies have been tested.

 

• Programming synthesizer code Tx nibbles (in bytes B, C, D, E and F) with hexadecimal C_ F_ F_ F_ F_ creates an Rx only mode. Pressing the PTT will sound an audible alert tone on the radio’s speaker and the Tx PA will not be activated.

PL, DPL, MPL, Talkback, Syntor X, Syntor X9000, and System 90*s are â trademarks of Motorola Inc.

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