Archives February 2011

Radio Hire Use Cases

How to Effectively control your Stewards During an Event

Stewards play a crucial role during any event.  Crowd control and safety being one of their critically important roles.

If an emergency situation was to occur, for example with a member of the public becoming ill of injured, time is of the essence.

Two way radio systems can be configured in number of ways to help stewards and event organisers effectively cope with emergency incidents.

For example, a button on the radio can be assigned so that when it is pressed an alarm alert is raised with the event controller, or other stewards.

Radios incorporating GPS technology can help other staff members track and locate a particular stewards location. This is an important feature, as it allows medical assistance to quickly be directed to the correct location, saving valuable time.

Another benefit of GPS technology for the stewards and management, is that the stewards may have been subcontracted from an external contractor, and therefore not be familiar with the layout of the event location. Therefore the GPS tracking technology eliminates the risk of potential confusion and uncertainty, as to exact location, when explaining where the incident has taken place.

For stewards that are working in remote locations within the site, a ‘Man Down’ solution may be appropriate. This solution prompts the radio user to press a button on the radio at a specific set time interval.

If the button is not pressed when prompted, then an alert alarm is sent back to the system controller. This system helps ensure that all stewards are ok, and if not, help can be sent out.

There area a range of options that can be configured into a radio system to help stewards with their duties, and we are more than happy to help you achieve the best possible system for your events particular circumstances.

radio communications services

School Cybersecurity over Two-Way Radio

School Cybersecurity over two-way radio is an important, as part of GDPR & Safeguarding.

Many schools have been sold ‘Walkie Talkies’, and other radio communications devices, through misleading advertising.

Private Channel

Private channel is a phrase that we have come across in two-way radio marketing, and its misleading.

Phrases like private channel, and privacy channels, mean that you aren’t likely to hear anyone else on your chosen channel.

It doesn’t necessarily mean that eavesdroppers cant listen to your conversations.

CTCSS & Colour Codes

CTCSS is short for Continuous Tone-Coded Squelch System.

It is a sub-audible tone that is added to a radio transmission to help reduce interference from other radio transmissions on the same frequency.

It allows multiple users to share the same frequency without hearing each other’s transmissions.

CTCSS is  used in analogue two-way radio systems, such as those used by businesses, schools, and public safety organisations.

CTCSS tones are typically in the range of 67-250 Hz.

Colour codes are used by two-way radios that use a digital transmission standard.

DMR (Digital Mobile Radio) is a digital voice and data standard for professional mobile radio (PMR) users.

DMR colour codes are used to divide a DMR channel into multiple “talk groups” or virtual channels.

Each talk group can have its own colour code, which is used to differentiate it from other talk groups sharing the same frequency.

In DMR, each radio has a unique ID, and each talk group has a unique ID, and when a radio is set to a specific colour code, it can only hear and talk with radios that are also set to the same colour code and same talk group ID.

This allows multiple users to share the same frequency and still maintain privacy and avoid interference.

Colour codes  identify different groups of users on the same frequency, so the radios can filter out transmissions not intended for the user’s group.

The Colour code is a setting on the radio, to join a specific group of users, and it’s usually set by the radio administrator.


Many schools buy off the shelf radios.

These ‘should’ be what is known as PMR446.

PMR446 radios do not need their colour codes (digital), or CTCSS (analogue) to be set up by a dealer / administrator, as they come pre set-up.

PMR446 is a low power licence free type of handheld walkie talkie.

If your school has bought a higher power licenced, ‘off the shelf’, then its probably operating illegally.

In the UK, all non PMR446 business radios, require the relevant OFCOM licence.

GDPR Implications

If other people can potentially listen in to your radio communications, then confidential information, is potentially at risk of falling into the wrong hands.

Safeguarding Considerations

Safeguarding our students, includes keeping confidential data.

We are aware of confidential data concerning children, being communicated over unsecure two-way radio, in the past.


In summary, two-way radio systems using CTCSS and Colour Codes, are used to provide users with privacy from hearing other users of the same channel.

They also reduce interference in radio communications, from other users.

However, it’s important to note that these systems do not necessarily ensure complete privacy, as third parties may still be able to listen in on conversations.

Additionally, it’s important for schools and other organisations to ensure that the radios they are using are legally compliant, and to be aware of the implications of GDPR and safeguarding when considering your school cybersecurity over two-way radio.

Action You Can Take

We will come to your school, and review your existing two-way radio communications equipment.

Once you are informed, then you are able to make appropriate decisions, regarding improving your school cybersecurity over two-way radio.

Written by Craig Miles

(01522) 740818

Superyacht cybersecurity

Superyacht Cybersecurity

Superyacht cybersecurity refers to the protection of a luxury yacht’s electronic systems, including navigation, communications, and entertainment systems, from unauthorized access or attack.

This can include implementing firewalls, encryption, and secure login protocols to prevent hacking, as well as ensuring that software and systems are kept up to date with the latest security patches.

Additionally, physical security measures such as biometric authentication and surveillance cameras can also be used to protect against intrusions.

As technology advances, the risks of cyber-attacks on superyachts are also increasing, making it essential for yacht owners and operators to implement robust cybersecurity measures to protect their vessels and their guests.

Contact Craig on 01522 740818 for help and assistance.


Superyacht Cybersecurity, written by Craig Miles

What does UHF stand for?

UHF in radio communications  stands for ‘Ultra High Frequency’

The UHF frequency band covers the range between 300 – 3000 Mhz (Mega Hertz).

UHF in radio communications is particularly useful in built up area such as cities, as the ‘wavelength’ is shorter the higher up  in frequency you go. This means that the shorter wavelength (compared to VHF) allows the signal to theoretically  go round  and through objects better.

Another advantage is that the aerials are shorter than with vhf equipment (remember higher frequency = shorter wavelength = shorter aerial). This is particularly useful for discreet and covert police operations. Shop security radios are also normally UHF.

A theoretical disadvantage of UHF compared to VHF is a shorter transmission range, though there are lots of factors involved in deciding which system will work best, and UHF systems  can be made to go long distances (worldwide in fact) by using it  in combination with the latest  internet combined technologies.

What is a Radio Repeater

A radio repeater is basically a radio receiver, and a radio transmitter in one unit.

The receiver part receives a radio signal from a walkie talkie or mobile two way radio on one frequency,  and then re-broadcasts it out again on another frequency.

The point of a Radio Repeater system is to increase the broadcast range.  For example a handheld walkie talkie may only have a range of a few miles, and is fairly line of sight.

With a repeater the fairly weak signal from a handheld walkie talkie (5 watts on VHF for professional equipment) is re-transmitted at maybe 25 watts of  RF power. Thus the signal can be heard further away.

Repeaters are also useful when there are hills in between two radios wishing to communicate, as is the case at the relatively high frequencies that private business radios operate on. As the signals are mainly line of sight, a repeater located on top of the hill can receive the signal from one radio, and re-transmit it, which can be received by the radio on the other side of the hill.

Motorola MXP600 Tetra Superyacht Radio

TETRA Superyacht Radio Communications

TETRA is increasingly popular for superyacht radio communications.

Tetra is a digital trunked radio system widely used by emergency services around the world, and is security focussed.

The word TETRA is short for Trans European Trunked Radio.


TETRA provides superyacht crew and owners, with instant voice and data communications.

Communications are secure and reliable, which has two primary benefits.


Crew are able to instantly communicate around the superyacht, and even to distant tenders.

Instant secure communications can be used by Stews for coordinating guest requests.

Engineers can communicate between engine room and other areas fo the yacht.

Owners & Guests

Owners and guests are able to make requests.

This could be done either directly using the radio, or more likely via a service call button, linked to the radio system.


Tetra is a trunked type of radio system.

Trunked systems do not allocate users to a particular channel or frequency.

When a radio transmits, the system allocates a channel for communication to take place.

Therefore the sender of the transmission, and the receiver of the transmission, are allocated a channel for that conversation.


The advantage of allocating users to a channel each time, is channel efficiency.

marine radios

Marine Electronics Directive

The Marine Electronics Directive (MED) is a set of regulations established by the European Union (EU) for marine electronics equipment.

The purpose of the MED is to ensure that marine electronic equipment used in EU waters meets certain minimum safety and performance standards, as well as to promote compatibility between different types of equipment.

The Marine Electronics directive applies to a wide range of equipment, including navigation equipment, communication equipment, and monitoring and control systems.

The MED requires that equipment must be CE-marked, indicating that it has been certified to meet the requirements of the directive, before it can be placed on the market in the EU.

The MED is enforced by national governments, who are responsible for ensuring that marine electronic equipment installed on vessels flying their flag meet the requirements of the directive.


What is GMDSS?

GMDSS stands for Global Maritime Distress and Safety System.

It is an internationally recognized system for ensuring the safety of life at sea.

GMDSS is covered by the Marine Electronics Directive, or MED.

Entel HT649, is a GMDSS radio, which we can supply from stock.

The Entel HT649 is a certified MED radio, and carries the wheelmark logo.

MED wheelmark logo

Entel HT649 Brochure Link

MED Fire Fighter

The industrial grade DTEx Marine Fire Fighter Series, is designed and approved to meet the latest MED standard implementation regulation MED/5.20, and European ATEX directive.

The ultra durable fire-red coloured DTEx Series sets the benchmark for next-generation MED compliant Firefighter radios.

Standard features include high visibility OLED display, high torque ergonomic controls designed for gloved-hand use, and industry-leading IP68 2m 4 hours submersible rating, to provide 100% reliability and usability even in the most extreme conditions.


01522 740818

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