Ham Station Sheet Metal Ground Plane

Antennas requiring ground planes are called ground plane dependent and having an appropriate ground plane can greatly affect performance.

Ham station sheet metal ground plane.

Copper strap is sold at hardware and roofing stores as flashing. You can bond equipment together at rf by connecting each piece of gear to a copper strap or pipe with a short piece of strap or wire. It is found that for a monopole antenna like a quarter wavelength vertical the ground acts as a plane to reflect the radio waves so that an image of the top half of the antenna is seen in the earth. It is possible to simulate this function by replacing the real earth.

The individual station equipments already have their own ground reference but when they are interconnected grounding each equipment to the main ground bus as shown in fig 1 creates ground loops. Consider also that most cars have a coat of paint between the mag mount and the sheet metal. Sometimes we set ourselves up for problems without knowing it. Ham gear usually has a ground terminal just for this purpose.

3 the problem is not rf at all but is a dc power supply ground loop back into the audio system. Each time a ground loop is created a small inductive coil is formed the ground wire completes the loop. Ideally you d have a ground plane of around 1 4 wavelength in radius which a pizza sheet can provide on vhf uhf bands but isn t even close on the hf bands. A ground plane is a reflective metal surface that the signal from an antenna bounces off of to better meet the antenna s design goals.

A very large pizza sheet might be around a meter in diameter or iow 50cm in radius. Then connect the bonding strap or pipe to your ac safety ground rod with a heavy wire. Why or when is a ham station ground necessary. I guess what i m simply not clear on is how a mag mount antenna s ground plane is connected electrically.

Used under and in back of equipment this 1 16 inch thick pre drilled copper sheet creates an rf reference plane that is typically connected to the existing grounding bus. K7trf aug 19 2016. 5 we have poorly installed connectors or defective cables. 4 equipment has a design defect.

Both of these should result in some level of electrical isolation between the antenna feed shield and the sheet metal. Dx engineering radio rf ground plane kits provide an effective method of reducing stray rf pickup by equipment and interconnecting cables.