Contributors

Reading this document

On going development of this document is being done in the MO-ARES yahoo group. Alternately, you may email your comments/suggestions to Bryan at k0emt@arrl.net.

Why

In the event of an emergency or exercise, an interoperability plan can address connectivity issues and increase the effectiveness and speed of the response.

The idea is if you have these VHF frequencies in your rig, you will be able to start working as a communicator no matter where you are in the state. This plan is designed to augment your existing structure, not totally replace it. If you have an operational repeater or simplex net, by all means utilize it. However, please continue to monitor HVCall.

The APRS/Packet/DATA frequencies are meant to supplement your existing plan and the Missouri Emergency Packet Network (MEPN).

Example:
Instead of having one Moniteau ARES op contacting Cole ARES to pass traffic for MARS on one freq and another Moniteau op contacting Morgan ARES to pass MESN traffic on a different freq (both with active directed nets- assuming we know the frequency on which to contact them). One op could go to "HVCall" and contact the Liaison stations for Cole and Morgan. Once they have made contact they could QSY to HVTac6 to pass the traffic, leaving the call freq clear. "Morgan, QSY to HVTac6, I'll call you. Moniteau, K0EMT."

Neighboring Districts only need to know the one frequency to contact each other.

Naming

To alleviate confusion, standard mnemonics shall be used in all equipment to refer to individual channels. These are listed in the table below. Should the equipment not be capable of alphanumeric channel mnemonics, the radio should be placarded to indicate the channel mnemonic and its corresponding position on the radio's selector switch.

Naming Guide

• V refers to 2M VHF
• U refers to 70cm UHF
• L refers to 6M 'Low Band' VHF, scene ops
• M refers to 6M 'Mobile Low Band' VHF, wide area/mobile

Frequencies

VHF 'Wide Area' Frequencies

UHF 'Scene' Frequencies

6M 'Wide Area/Mobile' Frequencies

6M 'Scene' Frequencies

Repeaters

Specifics for repeater use will be determined on a per incident basis. Use the simplex part of the plan to disseminate the repeater frequencies and PL. Operators should be prepared (have manual) to program odd splits if needed, PL's, etc.

Mode of Comms

20K0F3E, standard FM voice.
As NBFM becomes more prevalent in the future, this may be revised.

Tone/CTCSS

Calling frequencies - NO PL, NO CTCSS, NO DCS
Tactical frequencies - PL/CTCSS 100.0

This Tone was chosen to avoid interference from or interfering with Public Safety entities using 156.7.

Do NOT use CTCSS unless needed to help manage QRM.
ALWAYS transmit PL.

Power Output

Users are strongly encouraged to increase antenna gain and directionality before increasing power.

No more power than the minimum needed to establish a near full-quieting circuit.

Adhere to the FCC regs requiring the use of the minimum power needed to establish the circuit and RF Safety limits.

VHF - 2M and 6M

UHF

The UHF frequencies are intended for on scene operations. For this reason and to minimize the possibility of interfence with other stations:

Time Out Timer (TOT)

All stations operating in mobile relay mode, where permitted, shall be configured to immediately drop transmit carrier upon cessation of input signal. Reasonable hysteresis time in squelching action of weak received signals, or in signals that have achieved a critical bit error rate (BER) are permitted. Prolonged "hang time" in excess of 500 ms is not permitted.

Priority Levels

1. Emergency or urgent operation involving imminent danger to life or property;

2. Disaster or extreme emergency operation for mutual aid and inter-agency communications;

3. Special event control, generally of a preplanned nature (including Task Force operations)

4. Joint training evolutions

   To resolve contention within the same priority, assuming all radio equipment is exercising the lowest output and effective radiated power level practicable, the channel should go to the organization with the wider span of control/authority. This shall be determined by the SEC/DEC for the operation or by the levels of authority/government identified in the contention.

Use

Calling

After contact has been established, change frequency to the primary frequency of the calling party or the frequency directed. The calling party will then initiate the exchange.

(See example above and Primary Intra-District Comms below)

Alert paging and SCADA operations are not permitted on Calling or TAC channels. Temporary base station receivers shall not be muted by either selective calling alert mechanisms or DTMF signaling devices.

VHF

• District to District
• County to County
• Mobile/Rover to County
• Incoming amateur response to IC or amateur section chief

HVCall IS THE PRIMARY CALLING CHANNEL OF THIS PLAN.

Command/NCS should have someone assigned to monitor this frequency.

HUCall, HMCall and HLCall are secondary calling channels.

Command/NCS may not be monitoring these frequencies.

UHF

Primarily Intra-County use and on site tactical use.

6M

The 'M' frequencies are for Point to Point and Mobile operations.
The 'L' frequencies are intended for on scene tactical operations.

Staging

Primary Intra-District Comms

APRS

HVAPRS is used for VHF APRS networks. HUAPRS is used for local UHF APRS networks.

Packet

Data

Local area determines protocol, DCC guidelines should be followed. May be used for PSK31, MFSK, 9600baud Packet, APRS, JT44, etc.

Could be modulated with either FM or SSB depending upon stations mode capabilities.

If additional data channels are needed, stations could move up in 10 KHz increments.

VHF

UHF

Since the tactical frequencies are intended for use by low power portable stations within a limited geographic area, you should be able to use the same frequency at multiple locations.

Suggested use of non-primary HVTac frequencies

Also, keep in mind that spectrum is a shared resource.
Do not interfere with any existing operation.

Command/Admin Net

Logistics/Resources

This person will work closely with Staging.
Ideal is to have them co-located.
Staging monitors HVStage.

Digital Modes

For instance, you have a team that is equipped with APCO 25 compliant gear. They are assigned to operate on HVTac0. The team leader is also monitoring/checked in to the Command/Admin net.

Tactical Frequencies

The shelter command should be monitoring and checked in to the Admin Net.

Shelter command should:

• Determine if a Tactical frequency is needed
• Determine a clear Tactical frequency
• Advise NCS of the local use of the tac freq, by name

• Continue Monitoring their Tactical frequency
• Continue Monitoring their NCS assigned Net frequency
• Advise NCS when the operation on the Tactical freq has terminated

Security

Distribution

Interoperability with Public Safety

Equipment used on these frequencies should be FCC Part 90 type accepted.

© 2010 St. Louis County ARES^®

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