CTCSS CDCSS

What is CTCSS?

CTCSS stands for Continuous Tone Coded Squelch System.
Interference-Elimination Codes, sometimes refer to Tone Squelch, TalkGroup or Privacy Code.
It works like Key and Lock on Door. Walkie Talkie transmits sub-audible tone (Key) and opens the door (Lock) on Receiver. For example: Group A on Ch1 no CTCSS, Group B on Ch1 Code1, Group C on Ch1 Code38. Group B won/’/t be bothered by Group A (no Keys) C (wrong Key).  Group A can hear all groups because no Lock (incoming door is open).

Keep in mind that this feature doesn/’/t actually protect your privacy. As you see Group A who turned off CTCSS can hear all in the same channel. In addition, anyone who has chosen the same channel and code as you can still transmit to your radio.

 

CTCSS 38ch Standard Frequency Table

CTCSS FRS No.	Hz	CTCSS FRS ch	Hz
1	67.0	20	131.8
2	71.9	21	136.5
3	74.4	22	141.3
4	77.0	23	146.2
5	79.7	24	151.4
6	82.5	25	156.7
7	85.4	26	162.2
8	88.5	27	167.9
9	91.5	28	173.8
10	94.8	29	179.9
11	97.4	30	186.2
12	100.0	31	192.8
13	103.5	32	203.5
14	107.2	33	210.7
15	110.9	34	218.1
16	114.8	35	225.7
17	118.8	36	233.6
18	123.0	37	241.8
19	127.3	38	250.3

CDCSS  

Standard(N)			Standard(N)			Standard(N)			Standard(N)
											23	23	143	143		266	465	465
25	25			145		271	271		466	466
26	26		152	152			274		503	503
31	31		155	155		306	306		506	506
32	32		156	156		311	311		516	516
	36		162	162		315	315		532	532
43	43		165	165			325		546	546
47	47		172	172		331	331		565	565
51	51		174	174			332		606	606
	53		205	205		343	343		612	612
54	54			212		346	346		624	624
65	65		223	223		351	351		627	627
71	71			225			356		631	631
72	72		226	226		364	364		632	632
73	73		243	243		365	365		654	654
74	74		244	244		371	371		662	662
114	114		245	245		411	411		664	664
115	115			246		412	412		703	703
116	116		251	251		413	413		712	712
	122			252		423	423		723	723
125	125			255		431	431		731	731
131	131		261	261		432	432		732	732
132	132		263	263		445	445		734	734
134	134		265	265		464	464		743	743
									754	754