Operating instructions
DMH Series VHF Radio  Installation and Programming 
BK RADIO  Page 2-19 
2.4  CTCSS CHANNEL GUARD VALUES 
The CTCSS Channel Guard system may be set for any frequency in the range of 67 to 255.9 
Hz. However, since most systems adhere to the Electronic Industry Association (EIA) 
standards, tones should be selected from the following EIA list. In order to insure optimum 
performance, tone selection for use on the same radio frequency (RF) channel or adjacent 
channels in the same coverage area should be made from one of the Groups A, B, or C to 
the maximum degree possible. 
GROUP A  GROUP B  GROUP C 
 67.0 (XZ) 
 77.0 (XB) 
 88.5 (YB) 
*100.0 (1Z) 
 107.2 (1B) 
 114.8 (2A) 
 123.0 (3Z) 
 131.8 (3B) 
 141.3 (4A) 
 *151.4 (5Z) 
 162.2 (5B) 
 173.8 (6A) 
 186.2 (7Z) 
 203.5 (M1) 
 218.1 (M3) 
 233.6 
 250.3 
 71.9 (XA) 
 82.5 (YZ) 
 94.8 (ZA) 
 103.5 (1A) 
 110.9 (2X) 
*118.8 (2B) 
 127.3 (3A) 
 136.5 (4Z) 
 146.2 (4B) 
 156.7 (5A) 
 167.9 (6Z) 
*179.9 (6B) 
 192.8 (7A) 
 210.7 (M2) 
 225.7 (M4) 
 241.8 
 74.4 
 79.7 
 85.4 (YA) 
 91.5 (ZZ) 
* 50/60 Hz power distribution systems could cause falsing. 
The assignments in a given area shall be made from within one of the Groups: A, B, or C. 
2.5  CDCSS CHANNEL GUARD VALUES 
Codes for the CDCSS Channel Guard system may be chosen from the following list.  Since 
there are no EIA standards for the performance or compatibility of CDCSS Channel Guard 
systems it is recommended that an operational test be made on the intended system before 
wholesale assignments are made. In some cases either or both transmit and receive codes 
will require an inverted code to operate with existing systems. This can be done during the 
code programming of the system. Usually systems using direct Unit-to-Unit transmission 
(systems without mobile relays, repeaters, remote control, etc.) may use codes from the 
table. Systems with relays, etc., may use code variations for systems control and operational 
efficiency. The system operator or engineer should be consulted regarding the operational 
requirement on such systems. 
023  065 131 165 245 315 411 466 612 703 
025  071 132 172 251 331 412 503 624 712 
026  072 134 174 261 343 423 506 627 723 
031  073 143 205 263 346 431 516 631 731 
032  074 152 223 265 351 432 532 632 732 
043  114 155 226 271 364 445 546 654 734 
047  115 156 243 306 365 464 565 662 743 
051  116 162 244 311 371 465 606 664 754 
054 125     










