TWiRT 38 - Hot Air and Field Day

How to handle hot air at the transmitter site.  SBE responds to being left out by the FCC.  And Tom Ray invites you to Amateur Radio Field Day.

Kirk Harnack - Executive Director, Int'l Business Development, Telos-Omnia-Axia
Tom Ray - VP, Engineering, Buckley Broadcasting, WOR, New York, W2TRR
Chris Tobin - CBS Radio, New York
Chris Tarr - Entercom, Milwaukee, GeekJedi, and Broadcast Engineering Info

Show notes:

Letter to the FCC from the Society of Broadcast Engineers

ARRL Field Day

Download the show here...

TWiRT 38 - Hot Air and Field Day

Comments

[Peter Smerdon]

Another good topic guys.

One other thing to mention about air handling is to keep the transmitter's own air filters clean.

These days, with stable, reliable solid-state transmitters it just might be the most critical item of preventative maintenace left (right up there with regular generator load-tests).

Clogged filters causing low airflow thru the transmitter is a sure way to trigger premature failures - like on the next really hot day.

Oh, and I've retrofitted aircon into two transmitter buildings which previously had thermostat controlled ventillation fans. One in Brisbane in 1986, and one in Melbourne in 2006.
In both cases relibility improved.
I also left the vent fans in place at both sites, with their thermostats turned right up so they would only start if the aircon failed. In the later install, where I had plenty of remote control status channels, I set up an alarm for when the fan was running.

[Brian Urban]

A couple of tips on air conditioners. Put a low ambient kit on the unit--it will help prevent the unit icing up when outside temperatures get near the dewpoint. Really necessary in the south where winters don't get really cold and the A/C runs year around. Look into hot gas bypass when purchasing a new unit, especially if no heaters are installed. This will allow better humidity control in the building. Relatively cheap to install in a new unit at the factory, impossible to retrofit as it voids the refrigeration circuit warranty.

Controllers that switch primary/secondary units are commonly called lead/lag controllers. Bard seems to be the primary manufacturer. They can be retrofitted on existing systems as they are standard thermostat wiring. See
http://www.bardhvac.com/digcat/volume_3_cd/install_pdf_file/2100_telecomcntrlinfo.pdf
for installation details

[Brian Urban]

correct url for Bard controllers

http://www.bardhvac.com/digcat/volume_3_cd/install_pdf_file/2100_telecomcntrlinfo.pdf

[Brian Urban]

well, the url is still truncated. should end in .pdf