[Lowfer] New idea for Lowfer transmitting

[Bill Ashlock]

Bob,

>there is a good near field device that can be calibrated to determine
>ERP in the RSGB's LF handbook. Consists of a direct conversion rcvr
>that is calibrated to a DMM with a Helmholtz coil. The article is a good
>read

Yes, I've read this article in detail. One of the problems with this 
approach is the DC receiver. This unit uses a low beat frequency to get 
around some of the problems but this makes for a poor audible copy - and the 
audio is important when measuring weak lowfer signals at up to and sometimes 
exceeding 100 miles. A good DC receiver is probably more complex than my 
superhet SVM.

Another problem I find is using an H-probe antenna. It's a mess trying to 
hold the antenna, the head phones, and the SVM at the same time. I much 
prefer my mag mount E-probe which allows me to stay in the car. The trick is 
to stay at least 100ft from any group of trees and I find this to be not 
much of a problem.

The most difficult problem to overcome with either probe type is the 
presence of power line noise on just about any road you drive these days. I 
make measurements in large parking lots, cemeteries (avoiding ghosting <G>), 
school playgrounds, and even off the side of interstate highways.

Bill

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