Topband: Finding buried radials

[Tom Rauch]

> Does anyone know of a way to find buried radials, short of 
> digging up the backyard? I've tried a dip meter and a 
> field strength meter all to no avail. Want to add more 
> radials between the ones I have, but after several years 
> not sure where they are. Thanks for any and all help. Ron 
> KB7ZR


Ron,

I fashioned a loop antenna out of copper tubing gapped the 
top and soldered to a double sided PC board box. It has a 
long metal handle so I can hold it a few feet away.

The box has a simple J310 FET and a tuning cap and 
bandswitch that switches in padding caps.

I use it with a portable noise locating receiver but there 
is no reason it would not work with a portable SW BC 
receiver.

What I do is snap a large ferrite bead wound with several 
turns of wire over the wire or cable I am trying to locate, 
and connect my MFJ-259 to that bead winding. That way I can 
excite the cable or wire with RF.

I can locate cables that are two or three feet deep with it. 
I can literally find a cable that is a few feet deep within 
inches of the exact location. Of course it is MUCH more 
accurate for a surface wire.

A metal detector will not work because it runs on such a low 
frequency it can't detect things the size of straight wires 
less than 1/2 inch or so diameter unless it is iron or 
steel. There just won't be strong enough eddy currents in a 
small diameter copper wire. I find 1/2 inch or large cables 
near the surface with my metal detector, but deep buried 
cables or small wires near the surface  require a loop 
antenna of some type and a signal source of some type that 
injects current in the wire.

You MIGHT be able to ground one end of an ohm meter to the 
radial junction and probe the earth with the other probe. 
I've seen that work before with an analog meter, Simpson 
260, on high ohms scales.

73 Tom