Amateur Radio Antenna Conduits - Work in Process

Work is coming along as we get our new Antenna Feed Conduits installed up to the roof.

This is being installed in the back corner of the warehouse next to the main Electrical Circuit Breaker Panels. Two conduits; one with 6 coax cables installed, and the other with a 12 conductor signal cable and electric power line.

The bottom steel NEMA box currently has 6 each, type N coax connectors. The internal coax and cabling inside the conduits will be installed. There will be conduit pull tapes installed to easily add future cables as we need them. The U shaped wall mounted brackets in the photo have been extended to the left to enable future conduits if needed. To the right of the box is a piece of angle iron that will support overhead cable trays that will extended over our operating and work benches.

The conduits have been installed through the roof. The roof was re-sealed again. These conduits will be shortened to be about 6 inches tall to connect to a matching weatherproof steel NEMA box on the roof.

The roof top box is still under construction. The coax lightning arresters still have to installed. The terminal strips you see in the photo is for the control cable terminations. The box will be installed on pressure treated 4x4 lumber to keep it off the roof for drainage purposes. We are adding an electrical outlet on the inside and outside of the box for auxiliary uses. Still awaiting some parts that will arrive this week.

This means that next weekend, weather permitting, we should be able to install the roof top box. We have a roll of LMR400 coax, the crimp style coax connectors, the brand new crimping tool, and the coax cable stripper tool.

Question: Does anybody have any experience installing coax connectors? We could sure use your assistance next weekend.

We are getting closer to a full operating Amateur Radio Station at the Dallas Makerspace.


I’m very familiar with coax crimps for n type. Actually most types. I’ll see about grabbing the kit from work for chamfered etc.

Hope that counts as one penetration and not two…

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I expect Rich can clarify, but my understanding is that under a certain size, does not count as a roof penetration as defined by the landlord. So this is actually zero penetrations per our contract.

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A conduit is not a penetration. If you ever get up on the roof you will see that any of the large A/C units have the large opening and multiple conduits for AC power, thermostat wiring, drainage, etc.

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Thomas @benemorius did the “pilot” holes Sat night.

The last pict is checking / marking the holes topside.

edit - A reminder to the AR SIG @Team_Amateur_Radio - Y’all need to start having mtngs to decide on what you want to do.


Been talking on the dfwtraffic net, expect to see some emails soon

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Event scheduled for Saturday after the DPRG meeting, if another admin will publish (I don’t feel it appropriate to push it myself since I created it)



I feel the same way; approving something I submit is a conflict of interest…

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@benemorius Did you move back or just visiting?

Today I finished assembling the roof top steel NEMA box. The conduit mating connectors were installed. All of the coax lightning suppressors were mouted with a solid copper backing plate. A separate grounding lug was also installed. Ready to mount on the roof this weekend.


Do we have the ability to receive ADS B data at the space? If we currently don’t, I can start another thread to discuss possibly adding an antenna to receive the data.

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I’m usually busy Second Saturday of each month.

I’d like to attend, but won’t be available until evening, if then.

I’m not aware of an ADS-B receiver at the space. That would be an interesting project.

The Roof Top Antenna unit is now installed on the Roof.

Inside the unit are the Lightning Suppressors mounted to a copper grounding plate. Not shown in the picture is the heavy copper grounding wire that is now connected to the copper plate and down the one conduit to connect to the inside box.

On the other side of the box is a GFCI electrical outlet inside the case and another outlet mounted on the outside of the case. There is a 15 conductor cable that is wired to the terminal blocks for auxiliary connections.

Notice that there are pull tapes already installed in the conduits. Ready for the coax runs and whatever we wish to add later on. The key to unlock the cabinets will be setting on top of the wall mounted cabinet by the new Amateur Radio area.


Duct seal the conduits to keep the condensation down.


This is amazing work. The install is top notch and will support the SIG for a long time to come. Congrats to everyone who contributed to the work!

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A very big Thank You!

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Great work. I did a lot of antenna installs/coax runs when I was working in LMR but most of the time the customer had another contractor install the conduits and roof penetrations. I have to say, this looks 100x better and cleaner than 99% of the runs I had to work with in the past.

If we have the tools needed, I would gladly help with coax runs when I’m off work. I don’t have my crimpers or heliax prep bits anymore as I work in a different field nowadays. I may be able to get coax/connectors at cost through a friend though.

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For those who wonder, The temp difference if not sealed will cause condensation when going from a conditioned to non-conditioned space. I had to argue with an electrical contractor about this, Which I then showed him the condensation & he still balked about putting in $5 of duct seal.