Comsec Associates, Inc. @ComsecGov

Testing, Inspections, Training, Code Development, and Compliance Consulting for In-Building Public Safety Communications Systems BDA DAS ERRCS comsec.us La Canada, CA Joined October 2008

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Comsec Associates, Inc. @ComsecGov

4 years ago

This ERRCS was tested after installation, and had its annual inspection done by a large alarm company, and both identified that the donor antenna alarm wasn’t working correctly. A check of the alarm connection revealed the installer failed to strip the insulation off the wires.

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Comsec Associates, Inc. @ComsecGov

4 years ago

The weather today is why we push for proper lightning grounding for your installations, unlike the zip-tied lightning arrestor shown here.

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Comsec Associates, Inc. @ComsecGov

4 years ago

I have yet another horror story for you. The installer wanted to save money installing a public safety system into a 25 story building. The solution: mount corner reflector antennas on the roof pointed down.

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Comsec Associates, Inc. @ComsecGov

4 years ago

Antenna feedline grounding kits come with weatherproofing for mounting outdoors in the elements. If you attach the ground kit inside a sealed NEMA-4 enclosure, there is no need for weatherproofing within the enclosure.

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Comsec Associates, Inc. @ComsecGov

5 years ago

Did an annual inspection recently on a DAS that didn’t seem to be working very well. The installers didn’t cut any cables to length, leaving dozens of coils of exposed antenna feedline. I’m amazed the fire and electrical inspectors let this go during final inspection.

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Comsec Associates, Inc. @ComsecGov

5 years ago

This is how to ground a lightning arrestor. This box is attached to the EMT conduit at the building entry port.

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Comsec Associates, Inc. @ComsecGov

5 years ago

Just to be certain we’re all clear on the concept, lightning arrestors don’t arrest lightning unless they are grounded. We find far too many floating lightning arrestors.

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Comsec Associates, Inc. @ComsecGov

5 years ago

Please cut cables to length. I had to issue a correction for this one today.

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Comsec Associates, Inc. @ComsecGov

5 years ago

To clear up a common misconception, this is what grounding looks like.

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Comsec Associates, Inc. @ComsecGov

5 years ago

This is NOT what grounding looks like. If your ground bars look like this, replace them before an electrical surge makes the decision for you.

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Comsec Associates, Inc. @ComsecGov

5 years ago

Yes, there is a service antenna up among the conduits.

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Comsec Associates, Inc. @ComsecGov

6 years ago

Very nice installation by HCI. They needed to drop the antenna a bit to clear piping, and unlike a lot of installers, took the trouble to install it properly.

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Comsec Associates, Inc. @ComsecGov

6 years ago

Saw this in an apartment building. Not sure if they are worried the antenna will be stolen, or will escape.

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Comsec Associates, Inc. @ComsecGov

6 years ago

This should work well. Feels like something is missing..?? Oh well, let’s go grab a beer.

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Comsec Associates, Inc. @ComsecGov

6 years ago

Taking grounding to the extreme.

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Comsec Associates, Inc. @ComsecGov

7 years ago

The installer couldn’t understand why the in building coverage wasn’t working as predicted.

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Comsec Associates, Inc. @ComsecGov

7 years ago

The local AHJ has a requirement that the signal booster system be shielded from nearby simulcast sites, and direct the majority of energy to the more distant donor site. The contractor retained the RF engineers at Tech/Knowledge to design the system, and this was their solution.

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Comsec Associates, Inc. @ComsecGov

7 years ago

A best practice is to mount antennas using nuts and bolts. Please refrain from jamming antennas under conduit and “calling it good.”

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Comsec Associates, Inc. @ComsecGov

7 years ago

A best practice is to have indoor “service” antennas visible from 360 degrees around the antenna. Playing “let’s hide the antenna behind metal” blocks signals from and to the antenna.