Weather Station Setup FAQ

Weather Station Hardware Setup

How far above the trailer roof should I mount the remote sensor?

Four to five ft. above the roof is sufficient.

What should I use for a pole?

Use a  7/8 inch outside diameter (OD) pole for the mast when you set up. You can use a telescoping fiberglass pole designed for Tractor trailer cleaning or pool cleaning. You can use a pvc pipe, or make an aluminum pole.

How long can the remote sensor cable be?

We recommend and can supply a 100 ft db9 cable for the Alta and AltaCom2. The ACx and AC4xR use a cat5 cable, and during weather station setup you can use a 100 ft. cable which we supply.

(AC2) Can I get a remote sensor extension cable (serial cable) locally?

No, even if the pin-out is correct you will not have sufficient ground for the sensors and your temperature and RH readings will be artificially high and erratic.

Can I put the antenna up near the remote sensor?

Yes, but you need to mount the antenna on a large piece of metal, at least one ft. square. This is called a reflective ground plane and will help you get the best distance on paging.

Can I make the antenna cable longer?

You do not want any total cable length greater than 35 ft. Even though we supply a quality low-loss cable, adding distance and connections will weaken transmit distance.

How do I mount the J20(AC2) J40(AC4x and 4xR)?

Use an electrical outlet box and cover designed for outdoor use (a deck or an RV) so the connections will be watertight when not in use. The covers can be either 2 separate flip ups or a full face flip up.

How do I orient the Anemometer (wind speed)?

There is a silver mark on the wind sensor that indicates zero degrees, or a direct headwind. During weather station setup for drag racing, you should orient the silver mark parallel to the track pointing down track. This means that a 0 degree wind is always a headwind and 180 degrees is always a tailwind no matter what track you go to. There is a diagram in the weather station setup manual that illustrates this.

Weather Station Software Setup

I’m Having Trouble Connecting Merlin to my Weather Station

In brief you need a current Windows Operating System, the current version of Merlin, and correct drivers for the cables that connect between the weather station and your PC. Here’s a weather station setup document that covers serial connectivity in detail for all Altalab weather stations.

Download Merlin Software, most current version.

Download Merlin Manual

  • What Racers Say:

    "If you're running in the other lane, I'd prefer you get your weather off of the end of your finger .... but if you want to know what you are going to run before the lights come down on the tree, I'd suggest you have an Altalab in the trailer." Jeff White, Crew Chief NHRA Top Dragster