Mobileers Answer Page

Some thoughts about operating on the "Top Band"

Excellent article by Howard Francis, W9NHM on getting on 160 easily. Click here for W9NHM article	Antennas Antennas for 160 - click here
Feed line considerations Open line is best...but we can settle for coax, if you insist! We are also believers in antenna tuners or matching networks to assist in making the best match and best frequency flexibility. Click here for more information regarding feedlines on 160 meters	Grounding Information Click here for Grounding Details

Grounding methodology

Your ground system can never be robust enough! Put down more wire now!

	Visit W8JI for expert grounding information
Easy Way to Install Your Ground Wires	A nifty way to bury radials without any digging!
Important Polyphaser Notes	Great detail information on grounding your station.
Check Your Grounding Connections	How to verify your ground connections are good
A good source for open wire and coax arrestor systems	An interesting source for arrestors...at less cost from Polyphaser: Industrial Communication Engineers (ICE)

When operating on 160 a single ground rod will not work. You need to install a grounding system consisting of many radials all tied to a common point. This will provide excellent ground for RF and also can be part of your lightning protection. (An exception to this rule is if you are able to install a dipole or similar antenna that does not work against ground as a vertical does). Refer to the manuals and hand books shown below for more details on building your ground system for 160 meters.

We feel proper grounding (actually a ground system) is most important and most overlooked part of your 160 meter station. Hams often spend much time on their antenna and neglect their ground system. When working the higher frequency HF bands, the ground system may not be as essential as we find here on 160 meters. Thus hams become somewhat casual regarding the importance of a suitable ground system.

The following links contain a wealth of information regarding grounding and your ground radial system necessary for your antenna system. Notice that we always include the grounding system as a main part of your antenna system. A pair of 8 foot ground rods will not suffice here on 160 meters!

Grounding details at W9HLQ. Two copper straps tie the tower to the inside bulkhead plate. Copper block from power distribution panel is used to terminate my radial farm. Stainless steel is used to separate the copper terminal block from the aluminum tower. Stainless steel straps provide bonding forces. Everything is sprayed with water resistant lithium grease to reduce corrosion. It looks messy, but it works well.

Cables on the left go to the radio gear, the cables on the right side of the bulkhead go up and outside to the tower common ground point (see tower base photo above). It looks messy, but hopefully the lightning will not care.

Cables are removed from bulkhead when storms threaten. The bulkhead is grounded by heavy copper straps to outside tower common ground point, local water lines, and the electric power ground. Lightning surges may well travel down the feedlines and into the house. The bulkhead hopefully will then direct those surges to ground. Simple feed through coax fittings are used. A better system would include the use of gas discharge protectors.

Your Grounding System: How Many Radials Do you Need?

The following data is from the 2005 ARRL Handbook. The article is by John Stanley, K4ERO, in his December 1976 QST article. This will give you the trade offs when designing your 160 meter grounding system.

Notice that case #6 (*)is deemed as the best configuration, one that is used by commercial AM radio stations (120 radials and over 4 miles of wire!) Note that the minimal configuration has 16 52 foot long radials has a 3 db signal loss over the perfect situation - half your power is lost in the vertical antenna system (don't forget losses in your feed line and antenna tuner!)

* this is deemed as the best configuration - set as the standard of comparison (this chart is valid for 160 meters only)

Summary: a configuration of 16 radials each 50 feet long should be considered the minimum acceptable ground system.

Essential reading about grounding!

Useful grounding related links shown below:

Interesting links relating to our interests

Operating Mobile on 160 Meters

Operating mobile on 160 meters poses some real challanges to obtain a good signal. It can be done, but you need to pay attention to several factors that are not an issue when operating, say, on 2 meters. The reference material shown below addresses most of the issues concerning your 160 meter installation.

160 Meters with your Screw Driver Antenna by W9HLQ

Good reference material

Home | Picture Menu | Daily Gathering | Hint/Tips | Luncheon | Member List