Tone & Signaling Formats
 

CTCSS/PL

Continous Tone Coded Squelch (CTCSS) aka PL, Private Line™, & Channel Guard™ is used to differentiate each user on a single frequency. A sub audible tone is sent continuously during each transmission. Example Police Dept. 1 may use 131.8, Police Dept. 2 may use 107.2. It does not offer a "Private Channel" as many radio salesman would like the end user to belief. It is simply a way for multiple users to share the same frequency without hearing each others units. It does not allow multiple simultaneous conversations.

The chart below outlines the commonly used designators for the different PL tones.

The Wulfsburg Flexcomm is a frequency agile radio covering 30-512MHz commonly used on Aero-Medical helicopters. The tone # is programmed in when needed, and is often given on dispatch "Ground contact Engine 3-1-1 on 46 decimal 46, tone #14". This is a good way to find PL's for agencies to use with scanners capable of PL.

Tone/HzMotorolaWulfsburgIcomTone/HzMotorolaWulfsburgIcom
67.0XZ11136.54Z2520
71.9XA22141.34A2621
74.4WA33146.24B2722
77.0XB44151.45Z2823
79.7WB55156.75A3124
82.5YZ66162.25B3225
85.4YA77167.96Z3326
88.5YB88173.86A3427
91.5ZZ119179.96B3528
94.8ZA1210186.27Z3629
97.4ZB13192.87A3730
100.01Z1411203.5M13831
103.51A1512206.68Z
107.21B1613210.7M232
110.92Z1714218.1M333
114.82A1815225.7M434
118.82B2116229.19Z
123.03Z2217233.635
127.33A2318241.836
131.83B2419250.337
69.3WZ254.10Z

DPL

Digital squelch, or DPL, uses a small sub-audible digital code versus a sub-audible tone. You can have regular or inverted codes. This results from the electronics & system used to send the digital code & how it is recovered in the radio. This is not the forum to discuss the technical operation of DPL, suffice it to say that you get 2 codes for each of the standard DPL codes, normal & inverted. The chart below outlines both.

CodeInvertedCodeInvertedCodeInvertedCodeInverted
023047155731325526516432
025244156265331465523246
026464162503332455526325
031627165251343532532343
036172172036346612546132
043445174074351243565703
047023205263364131606631
051032212356365125612346
053452223134371734624632
054413225122411226627031
065271226411412143631606
071306243351413054632624
072245244025423315654743
073506245072431723662466
074174246523432516664311
114712251165445043703565
115152252462446255712114
116754255446452053723431
122225261732454266731155
125365263205455332732261
131364265156462252734371
132546266454464026743654
134223271065465331754116
143412274145466662
145274306071503162
152115311664506073
032051315423

DTMF Paging & ANI

Standard Dual Tone Multi Frequency (DTMF) aka Touch-Tone™ tones are used for both paging and Automatic Number Identification (ANI). DTMF is also used to activate features of some radio systems like phone patches, remote receivers/transmitters, or to activated alarms remotely.

DTMF ANI will sound like a very quick series of tones which may start, end, or start & end each radio call.

DTMF format paging sends digits for 100ms, 100ms off. Number of digits depends on system, usually at least 4 digits.

Knox format is similar to DTMF, uses different tones though, and is primarily used as a means to unlock special lock "Knox"boxes for fire departments.

DTMF Tones
1209133614771633
697123A
770456B
852789C
941*0#D
Knox Tones
1052116212971430
606123A
672456B
743789C
820*0#D

Digital ANI

Digital Automatic Number Identification (ANI) is way to send information back to the dispatcher. This information can contain the radio ID, users ID, vehicle location via Automatic Vehicle Location (AVL), be used as an emergency indicator or "Man Down" alert.

There are 5 digital ANI formats presently being marketed, these include Motorola MDC-1200™, GE/Ericsson GE-Star™, Transcrypt Flash Call, Control Signal, and Midian Zap. All 4 formats are proprietary & incompatible with the other. These systems also allow for stolen radios to be "stunned": to disable them, & to be activated for the dispatcher to listen in to the area around the radio.

You will know if a system in your area is using these, as it is a short digital burst that begins, ends, or both each radio conversation. Sounds like a short schreech.

5/6 Tone Paging & ANI

This format is used for both tone pager activation and for Automatic Number Identification (ANI). This format was originally developed for tone only pages using the MetroPage™ format (Metro PageBoy™ etc.). Pagers can have 2 addresses per capcode. Thus you could get two different alerts to the pager with two different meanings, Tone 1 Call Home, Tone 2 Call Office etc..

Today most of the 5/6 Tone pagers are gone, but the format lives on in ANI needs for Public Safety. ANI allows for the number of the radio to be sent on each transmission. You may have heard it as a long tone & a quick series of tones, or just a quick series of tones when each user starts a radio call.

The chart below outlines the tones used for the 6 internationally used formats. CCIR & ZVEI's are most commonly used in Europe. EIA/MetroPage is used in the US.

Tone #EIACCIRZVEI1ZVEI2ZVEI3/DZVEIPZVEIEEA
0600198124002400220024001981
174111241060106097010601124
2882119711601160106011601197
31023127512701270116012701275
41164135814001400127014001358
51305144615301530140015301446
61446154016701670153016701540
71587164018301830167018301640
81728174720002000183020001747
91869186022002200200022001860
A2151240028008858259701055
B2435930810810740810930
X/C20102247970740260028002247
D2295991885680885885991
R/E45921102600970240026002110
FNo Tone105568026006806802400
Timing
Preamble673ms673ms673ms673ms673ms673ms673ms
Gap65ms65ms65ms65ms65ms65ms65ms
Tone33ms40ms100ms100ms100ms100ms100ms
X Tone65ms40ms100ms100ms100ms100ms100ms

The Preamble is used as a battery saving mechanism, similar to todays digital pagers, thus the pager looks for its preamble, if not heard it shuts off to standby mode.Not all systems use the Preamble, that is why its called 5/6 tone paging. You may only have 5 tones when not using the Preamble.

In 5/6 tone paging a consecutive number is never sent. thus a pager with capcode 1-12344, would be sent using the a Preamble tone of 1/600Hz, followed by a 65ms gap of silence, then 2/882Hz, 3/1023Hz, 4/1164Hz each 33ms long, the second four is transmitted using the R (Repeat) Tone of R/459Hz.

The second address of a pager is activated by sending the X tone after the pagers capcode, thus 1-12345X.

The chart above inlcudes both 5/6 Tone & HSC Tones. For 5/6 Tone pagers only Tones 0-9, X, & R are used. Tones A-F are for use in HSC Pagers and 5/6 Tone ANI systems.

Hexadecimal Sequential Code (HSC) Paging

This format is an extension of the 5/6 tone paging format to allow for numeric display pagers versus the early tone only pagers using 5/6 tone formats. An example of these pagers is the Motorola BPR-2000. This format has been replaced by newer digital formats, and is only used on Public Safety systems, private systems, and some very small common carrier systems. New pagers are not available, used pagers are still available.

For EIA/MetroPage the timing of the tones is increased to 65ms. Upto a 12 digit message may be sent.

Tone #EIA
A2151
B2435
C2010
D2295
E459
FNo Tone

2 Tone Sequential Paging

This is the format most listeners will be familiar with. This format is the most common method to alert volunteer ambulance & fire departments. It has various names including QuickCall II™ & Type 99™. This format also goes by 1+1 in some radio equipment. This format uses 2 tones, A & B for standard paging, a third & fourth tones C & D are used to provide group call and second call to each pager.

This format uses a timing of Tone A for 1 second & Tone B for 3 seconds. For All Call Tone B is sent for 8 seconds, where all pagers have the same A tone. Group Call with Tone A & C, and Second Code Call with tone A & D.

The original form of this system, QuickCall I™ uses 4 tones, and is commonly called 2+2 paging. Where Tones A & B are sent for 1.25 seconds, and tone C & D are sent for 1.0 second. The 2+2 format only uses tones from the Motorola groups of A, B, & Z.

The GE version of this format uses Tone A 1.0 second, a gap of 180 ms., and Tone B 3 seconds.

The tables below outline the tones of the various groups for each series by Motorola & GE.

Tone#Mot. 1Mot. 2Mot. 3Mot. 4Mot. 5Mot. 6Mot. 10Mot. 11GE AGE BGE C
0330.5569.11092.4321.7553.91122.51472.91930.2682.5652.5667.5
1349.0600.9288.5339.6584.81153.41513.51989.0592.5607.5712.5
2368.5634.5296.5358.6617.41185.21555.22043.8757.5787.5772.5
3389.0669.9304.7378.6651.91217.81598.02094.5802.5832.5817.5
4410.8707.3313.0399.8688.31251.41642.02155.6847.5877.5862.5
5433.7746.8953.7422.1726.81285.81687.22212.2892.5922.5907.5
6457.9788.5979.9445.7767.41321.21733.72271.7937.5967.5952.5
7483.5832.51006.9470.5810.21357.61781.52334.6547.5517.5532.5
8510.5879.01034.7496.8855.51395.01830.52401.0727.5562.5577.5
9539.0928.11063.2524.6903.21433.41881.02468.2637.5697.5622.5
A
B
Diag.569.1979.9569.1569.1979.9979.9742.5742.5742.5

Tone #Mot. ACodeMot. BCodeMot. ZCode
0358.9CA371.5CB346.7CZ
1398.1DA412.1DB384.6DZ
2441.6EA457.1EB426.6EZ
3489.8FA507.0FB473.2FZ
4543.3GA562.3GB524.8GZ
5602.6HA623.7HB582.1HZ
6668.3JA691.8JB645.7JZ
7741.3KA767.4KB716.1KZ
8822.2LA851.1LB794.3LZ
9912.0MA944.1MB881.0MZ
A1011.6NA10471.NB977.2NZ
B1122.1PA1161.4PB1084.0PZ
Diag.979.9979.9979.9

QuickCall I codes may be used in two different forms: DZJZ-EZHZ or DJ-EH. They both have the same meaing, the first just specifices the tone series each time. The second assumes a given tone sereis is used, and known to the agencies using the system. The Diagonal Tone is not used in 2+2/QuickCall I systems, but when the A, B & Z series is used in the 1+1/2 Tone format this tone is used.

Plectron Paging

This is an early system used to alert many volunteer type organizations. This system uses a single tone sent,or two tones sent in one of two formats. The chart below are the standard Plectron tones.

Single Tone - 3 seconds of A tone
Slow Duotone - 3 seconds of A, .25 seconds of B
Fast Duotone - .75 seconds of A, .25 seconds of B

Tone #Freq.Tone #Freq.Tone #Freq.Tone #Freq.
282.2517.811992.0251820.0
294.7540.7121036.0261901.0
307.8564.7131082.0271985.0
321.4589.7141130.0282073.0
335.6615.8151180.0292164.0
350.52672.0161232.0302260.0
366.03701.0171287.0312361.0
382.34732.0181344.0322465.0
399.25765.0191403.0332575.0
416.96799.020992.0342688.0
435.37834.0211530.0352807.0
454.68871.0221598.0362932.0
474.89910.0231669.03062.0
495.810950.0241743.01957.0

Reach Tone Paging

REACH format is billed as a "High Speed" paging system very similar to the 2 Tone Sequential systems by Motorola & GE. REACH format uses a A tone of 2.0 seconds, and a B tone of 0.8 seconds. Group Call is 5 seconds. REACH tones are outlined in the table below.

Tone #Freq.Tone #Freq.Tone #Freq.Tone #Freq.
03960.0152354.0301400.045832.0
13824.0162274.0311352.046804.0
23694.0172196.0321306.047776.0
33568.0182121.0331261.048750.0
43446.0192049.0341219.049725.0
53329.0201980.0351177.050700.0
63215.0211912.0361137.051676.0
73106.0221847.0371098.052653.0
83000.0231784.0381061.053631.0
92898.0241723.0391025.054609.0
102799.0251664.040990.055588.0
112704.0261608.041956.057549.0
122612.0271553.042923.058530.0
132523.0281500.043892.059512.0
142437.0291449.044862.060495.0

Zetron Tone Paging

Zetron uses a series of tones for its Fire Dispatch & Alerting system.

The tones are outlined in the table below.

Tone # Grp. 1Grp. 2Grp. 3Grp. 4Grp. 5
01980.01177.01400.0832.0588.0
12704.01608.01912.01137.0804.0
22612.01553.01847.01098.0776.0
32523.01500.01784.01061.0750.0
42437.01449.01723.01025.0725.0
52354.01400.01664.0990.0700.0
62274.01352.01608.0956.0676.0
72196.01306.01553.0923.0653.0
82121.01261.01500.0892.0631.0
92049.01219.01449.0862.0609.0

SECODE/Digital Dial Alerting

This system is prevalent in the EMS community to "open a line" to hospitals to alert them to incoming patients from ambulance companies. The 2 standard tones used are 2805 & 1500. This system was also used by the older IMTS mobile telephones, prior to cellular.

The system sends a steady tone, and pulses this tone very similar to pulse telephone dialing.



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