Archives August 2021

intrinsically safe

Intrinsically Safe

Intrinsically safe two-way radios are essential for certain environments.

Environments such as gas installations, where there is a potential risk of explosion.

Explosive atmospheres in the workplace include flammable gases, vapours, and flammable dust.

An example of where vapours can be dangerous is in a ships battery room.

Vapour emitted from charging batteries, produces potentially flammable vapour.

Vapour can ignite, causing damage and potential loss of life.

Conventional walkie talkies pose a small potential risk of causing a spark.

A spark could result in an explosion.

The Dangerous Substances and Explosive Atmospheres Regulations 2002 (DSEAR) places duties on employers to eliminate or control the risks from explosive atmospheres in their workplace.

What is an explosive atmosphere according to DSEAR?

DSEAR defines an explosive atmosphere as a mixture of dangerous substances mixed with air, under atmospheric conditions, in the form of gases, vapours, mist or dust in which, after ignition has occurred, combustion spreads to the entire unburned mixture.

Atmospheric conditions are commonly referred to as ambient temperatures and pressures. That is to say temperatures of –20°C to 40°C and pressures of 0.8 to 1.1 bar.

What is ATEX?

ATEX is two European directives on controlling potentially explosive atmospheres.

1) Directive 99/92/EC (also known as ‘ATEX 137’ or the ‘ATEX Workplace Directive’) covers the minimum requirements for improving the health and safety protection of workers potentially at risk from explosive atmospheres. 

2) Directive 94/9/EC (also known as ‘ATEX 95’ or ‘the ATEX Equipment Directive) on the approximation of the laws of Members States concerning equipment and protective systems intended for use in potentially explosive atmospheres. 

The EU ATEX directives still currently apply to the UK.

ATEX intrinsically safe radios are available to meet the directive requirements.

ATEX radios are specially sealed to stop the risk of a spark causing an explosion.

lincoln UK

Lincoln Cathedral Two Way Radio

Lincoln cathedral now uses Hytera two-way radio to coordinate services and visitors.

Their existing otdated analogue based system was very old and needed replacement.

Yesway Communications’ were approached to quote for a new system, and we were awarded the contract;

A full radio range survey was carried out, including from the roof!

Whilst we were up on the roof, we surveyed the existing wireless communications systems, that are up there.

Being a high building on a high hill, the cathedral is naturally a popular place to mount an antenna on top.

This popularity has resulted in a number of antennas being mounted on the central tower roof.

Although modern digital two-way radio equipment such as the Hytera BD505 has excellent resistance to RF (Radio Frequency) intererence, we wanted to thoroughly analyse potential interference issues.

Lincoln cathedral is over 1000 years old and built of thick stone.

After extensive testing, we decided to move the system from VHF to UHF.

VHF is great in open country, but there was a coverage blackspot, that changing to UHF solved.

The original two-way radios used the older analogue technology, which is gradually being superseded by digital.

There are two types of digital two-way radios, DMR and dPMR.

DMR has emerged as the dominant standard in much the same way that VHS video recorders (remember them) became more popular than the Betamax standard.

The equipment we recommended to Lincoln Cathedral was the Hytera BD505.

Hytera BD505
DMR Digital Technology

The Hytera BD505 offers IP54 ingress protection, making it ideal for mainly indoor use, inside the Cathedral.

The compact design and DMR digital technology gives the cathedral a radio that is easy to carry, and with excellent sound quality.

Ongoing support and customer service is being provided, and we are so honoured and grateful to Lincoln Cathedral, for choosing us to serve them.

long range walkie talkies

Long Range Walkie Talkies

Long-range walkie talkies for hire have changed in recent years.

The traditional way was to use a repeater system.

A repeater system receives a weak signal and retransmits it.

This increases range.

Repeaters require an antenna system, located on a hill or high tower.

The reason that the antenna needs to be high, is to overcome obstacles and the curvature of the earth.

Obstacles such as hills and buildings, reduce or attenuate the radio signal. In the case of a hill, it will block a signal completely.

This is because radio signals used by walkie talkies, normally are at a frequency above 30 MegaHertz (Mhz).

Radio signals above 30 Mhz generally operate in a ‘line of sight’ manner.

Line of sight means that they go in straight lines, rather than bounce off the Ionosphere (for example), like frequencies below 30 Mhz.

The traditional way to cover a wide event coverage area was to use a repeater system.

The repeater system utilised a temporary antenna tower.

The tower would be located so that the antenna could ‘see’ over the object that was blocking the signal (such as a hill), thus extending the communications range.

Long-range walkie talkies are now available that do not need repeaters.

The new technology combines the instant communication of a two-way radio, with the coverage of a mobile phone.

By using the data capability of mobile phone networks, national or even worldwide coverage is possible.

Long range walkie talkies are available to buy and rent from Yesway.

By using this new technology, you do not require the expense of a repeater system and antenna.