I thought I'd start a new thread for this since it was brought up in the airspace thread. If you already know all of this, don't be offended, someone else may have forgotten.
If you are having trouble contacting FSS, first make sure they're the only ones that you're having trouble talking to to rule out radio trouble. Try to get a radio check from ATC or a unicom in the area to make sure your transmitter is readable. If that isn't possible, try to tune in an ATIS or ASOS to make sure you are receiving properly. We've all heard the guy who keeps transmitting "This is N1234, how do you hear me?" and somebody says "Loud and clear!" and then "This is N1234, can anyone hear me?" Make sure the volume is up and your audio panel is configured correctly. Most of us fly our own airplanes and we know how our equipment works, but maybe the mechanic or the kids messed with something or you bumped a switch.
Your antenna may also exhibit some directional characteristics depending on the installation. It may put out a stronger signal to the front or rear that it does to the sides. You might try turning 90 degrees and see if that doesn't help. You all know that VHF is line of sight, so climbing will increase the distance that you can transmit and receive. Approximate line of sight distance is the Square Root of two times the height of the antenna (altitude) or SQRT(2*A).
Height AGL Distance (statute miles)
1000 44
2000 63
3000 77
That's in theory anyway. I'm pretty sure I can't talk to anyone 77 miles away with my old antique Narco antenna and it's old wiring.
Now that you know your radio works, make sure you have the right frequency dialed up.
FSS antennae are either colocated with a VOR or NDB, or by themselves (RCO), or on the field with a FSS. The frequencies and the name of the station are indicated around the frequency box of the navaid or adjacent to the RCO symbol (looks like a circle with a dot in the middle). The common FSS frequency is 122.2, but it is not available at all locations. Coverage is said to be "most of the contiguous US from above 5000 feet." According to our line of sight calculation above, an FSS antenna could be as much as 100 miles away SQRT(2*5000)=100 (although I doubt that...maybe out in the desert?)
Probably the most common setup that you'll see is the FSS colocated with a VOR. The frequencies will be above the VOR "box" and the name of the station will be below it. If the freq. is presented with an R next to it (122.65R), that means the FSS can only receive on that frequency (not you). You transmit on that frequency and listen over the VOR or another VHF FSS frequency. If the VOR frequency is underlined, that means no voice services are available.
You should contact the FSS by name and give them the frequency that you are using and your location: "Montgomery County Radio, Cessna 1234A 25 north of Industry VOR on 122.2" Give them a little while to get to you. Sometimes there is a long line of pilots trying to get through. You may not hear them because they are talking on different frequencies.
References:
AIM 4-1-3, 4-2-2, 4-2-3, 4-2-6, 5-1-4,
EDIT: Forgot to mention that 121.5 will get their attention, too, but should be used in an emergency or else the "Guard Police" will start shouting at you from the flight levels.
Airline Guy: "You're on guard!"
Me: "So are you!" Or "Touche' " Or "I didn't know you speak French?"
