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The transmitter needs to be properly grounded. See this paper. Use #12 or #10 wire (Radio Shack 15-035 40 feet) or larger and connect one end to the binding post on the RANGEMASTER unit. The binding post on newer transmitters will accept up to a #10 wire. If you use a larger wire you will need to install a splice to connect to the binding post on the transmitter. Run the ground wire down to the ground with as direct a path as possible to a ground rod in the ground (Radio Shack 15-530 4 foot, 15-529 8 foot). Sometimes you can get away with using the electrical ground of a building for ground, often it will not work at ALL! Also using an electrical ground is Gray in the FCC rules, it just depends on any inspecting agent whether it will pass or not. If there is concern about the intentional frequency radiating into an electrical ground a choke could be used, see below. The transmitter needs a reasonably direct path to dirt ground with good penetration into ground. Some electrical grounds will not do this. If you find that you are not getting a sharp peak in voltage when you tune the cap tune then you probably are using an unacceptable ground (see troubleshooting document). This ground could also prove to be a bad lightning ground also. See the hints page elsewhere for an example how to run a good ground wire. The path should be as straight as possible to dirt ground. Avoid running the wire by or near metal on the way down.

Avoid Placing your ground rod to close to your house or building. The ground rod needs to be in good dirt away from the sand/gravel foundation fill of the structure. You can place the ground rod 10-20 feet away from the building and bury the wire (preferably un insulated) a few inches below the ground. What works well is to use a flat blade shovel to create a "trench" the the wire can be laid into. Just insert the shovel into the dirt a few inches and rock it back and forth creating a trench. This way the wire can be installed without digging. Two ground rods, a 4 foot right at the building for anchor and lightning protection with another 8 foot rod 10-20 feet away into the yard for performance can be a good system. The rod that is in the yard can be totally buried so it doesn't interfere with traffic, lawn mowing, ect. Remember, all connections must be soldered, or bright and shiny and the tightly clamped. What you are doing is making an electrical connection with the earth, the more copper / dirt contact the better. The wire coming from the transmitter needs to be locked down (mounted) so that it doesn't move. The most common range problem is with the ground, either a bad connection, or the ground isn't good. The ground rod has been put into sand or gravel. You want the ground rod into good loamy soil, real dirt, the moister the better. See this e-mail for further information

Here is what the FCC had in mind when they wrote subpart (b) on the following Part 15:

The idea seems to be that intentional radiators have a limit of 3 meters. The total length of the transmission line, antenna and ground lead (if used) shall not exceed 3 meters. The typical definition for "Ground lead" in engineering is, or similar to " A Wire connecting a device to a local ground or GROUND. So following this standard engineering principle the ground lead would be the wire connecting the transmitter ground binding post to the local ground. This "Ground lead" wire length plus the antenna would be the 3 meter limit. If you are mounting the transmitter to a existing Metal mast or tower an inspecting FCC agent may consider an isolated wire down to the dirt "Gray" in the rules but a dedicated copper path to the dirt is best for lightning protection.

See this document concerning Part15.219(b)

A good way to clean RF out of any circuit is a choke, an Amidon ferrite FT-193-J (Best) or FT-240-77 (Better) or FT-240-43 (good) could be used. The ferrite should be located right at the transmitter. We try to keep these ferrites in stock if you need them, or you can get them directly from Amidon. Keep in mind that for the lightning protection in the transmitter to be effective the DC resistance to ground should be low, so we recommend not using a choke that has a high ohms value. Using an inductor in series with the ground wire will degrade the response time of the lightning protection in the transmitter, however a 75 volt gas tube can be installed in parallel with the inductor to improve the response time. A possibility would be the F2726-nd gas tube available at www.digikey.com. Scroll down to the bottom of this page for a picture of a FT-193-J ferrite that has been used as a choke to limit radiation into a ground wire. Installation Guideline   Diagram

Section 15.219 Operation in the band 510 - 1705 kHz.

(a) The total input power to the final radio frequency stage (exclusive of filament or heater power) shall not exceed 100 milliwatts.

(b) The total length of the transmission line, antenna and ground lead (if used) shall not exceed 3 meters.

(c) All emissions below 510 kHz or above 1705 kHz shall be attenuated at least 20 dB below the level of the unmodulated carrier. Determination of compliance with the 20 dB attenuation specification may be based on measurements at the intentional radiator's antenna output terminal unless the intentional radiator uses a permanently attached antenna, in which case compliance shall be demonstrated by measuring the radiated emissions.

We recommend following FCC law and fully cooperating with the FCC. If you have any issues with an FCC inspection we will help sort things out and work with the inspecting agent to get you into compliance.

Groundplanes:

A good ground plane can help your signal. All you need is a solid or wire mesh plane below the transmitter. The radius of your ground plane should be about equal to the distance from the ground plane to the tip of your antenna.

The inner circle of #4 wire should be about a foot in diameter, place around the pole that mounts the transmitter, laying flat, perpendicular to the pole. The #12 wire spokes should be soldered to the #4 wire ring with electrical solder. The wire going to the transmitter can be #10 or #12, or larger.

Here are some examples of what other people have done: