To the venue owner – an ERRCS system is an expense with no ROI.
To the Emergency Responder – an ERRCS system is a MUST – with life safety for
responders, AND the public, depending on it.
Comba Telecom is committed to providing highly affordable,
state of the art solutions so venue owners can ensure
that First Responders get the coverage they need and deserve,
while making the cost to the venue owner as low as possible.
Comba's CriticalPoint 700MHz/800MHz single or dual band channelized Fiber DAS was designed
with public safety first responders in mind. Fully compliant with the IFC and NFPA (National Fire Protection Association),
CriticalPoint's Fiber DAS supports up to 32 channels (Class A) or 3 sub bands (Class B) along with 2W (Remote Unit) of downlink power per band. The channelized uplink squelch and channelized uplink AGC functions (Class A) ensure minimum interference to base stations and optimizes communications quality.
It includes comprehensive alarming capabilities, which supports all NFPA and IFC required monitoring and alarming, and also provides local and SNMP based remote monitoring. The built-in signal generator and isolation testing function provide great convenience to system integrators during deployments. Finally, the unit can be ordered either AC or 48V DC powered, allowing for flexibility depending on the design of the system.
In addition, by utilizing Comba's well-known high efficiency amplifier design, the Fiber DAS provides a very small footprint, light weight design, low electrical operating costs, and low UPS backup costs. Comba's total vertical in house design and manufacturing capabilities, and supply chain management resources, ensures that the CriticalPoint Fiber DAS is a very affordable, reliable and state of the art.
*Public Safety Fiber DAS MU FOU Expansion Unit, 4 port/8 port now available.
up to 32
band (Class A)
power for each
fast and easy
isolation test to
NEMA 4 enclosure
This provides Comba with much lower cost – and in addition, internal manufacturing also allows us to maintain a higher level of quality control and better control over lead times.
In addition, Comba's design team puts forth great efforts to ensure that there is no "over design" of any part of the CriticalPoint products, that could result in unnecessary extra weight or cost.
First, there is a mandatory isolation test that must produce satisfactory results prior to being able to commission the Fiber DAS.
Secondly – in the event that something changes the isolation (and causes oscillation) while the Fiber DAS is in use, the CriticalPoint BDA will shut down and issue an alarm.
Comba tests and certifies it's products through a Nationally Recognized Test Lab (NRTL) to meet the strict UL requirement standards. Click to view Comba's UL Standards Testing and Product Certification process pdf.
How does this work: our Fiber DAS amplifies and passes RF (radio frequency) – RF can carry analog traffic, or it can carry digital packetized traffic. As stated, our Fiber DAS is simply amplifying and passing the RF - we do not read, manipulate, or modify, nor really even "see" or know, what the traffic content is.
A way to look at this: consider the Fiber DAS and the antenna infrastructure as plumbing in a home or building – all the plumbing does is carry water. The water can be hot water or cold water - or could be potable or non-potable water – the plumbing doesn't care. And in a similar fashion, our Fiber DAS does not care what the traffic content over the RF is comprised of.
So how can analog and digital, which are different, be carried simultaneously? The end devices (base station and mobile devices) operate on either analog or digital – meaning that an analog device won't even see the digital traffic, and the digital devices won't even see the analog traffic. So – both types can be mixed over the same RF path with no chance of one interfering with the other.
To minimize or eliminate any call quality issues resulting from using these very narrow channel bandwidths, Comba has released updated firmware for our Class A Fiber DAS devices that allows for channel bandwidths of 75KHz. Utilizing a 75KHz channel bandwidth will result in group delay figure of 15usec maximum – which is well within the tolerances required for excellent call quality on P25 Phase II networks. This updated firmware is available directly from Comba and is available on Comba's portal which you can access here: Firmware Download
These kits are available directly from Comba – following is a link to the specification sheet for the kit; the specification sheet also includes the part number and other information necessary to order the kit. Link: BIAS-T KIT FOR NON-TRUNKED RADIO SYSTEMS
1. On your computer, open Chrome.
2. At the top right, click More Settings.
3. At the bottom, click Advanced.
4. Under "Privacy and security," click Content settings.
5. Near the bottom, click PDF documents.
6. Turn on Download PDF files instead of automatically opening them in Chrome.
Chrome will now download the generated Report.