"Hal Rosser" wrote in message
...


Please guys
Without going to war with each other over the answer and leaving me not
knowing who to believe, is an MFJ analyzer a good choice in the under
five hundred dollar range? Would using one of the one watt HTs do for a
signal source or is that still to high.
--
Tom Horne

Tom,

A one watt HT will do fine, but the signal will still be too strong close
in to work with. You need to get the power down to perhaps one milliwatt
or less to plot the antenna pattern in a field or car park. You can make
up an attenuator to reduce the power from the HT. Just making up a patch
lead between the HT and the antenna with a 50 ohm, 1 watt resistor
shorting the core and outer will probably reduce the signal to something
you can work with while still giving the transmitter a load to work into.
(You can make up exactly 50 ohms using two 100 ohm, 1/2 watt resistors).
Or make up a simple single transistor 'bug' transmitter from a handful of
components. Plenty of designs available through Google No need to spend
more than a couple of dollars. The 9v battery is likely to be the most
expensive bit.

Mike G0ULI

Mike's right - but if you don't have an MFJ 259 antenna analyzer yet, this
would be a good excuse to go ahead and get one. Its just great when
working with antennas.
You can get one for about half of your $500 budget.


Tom

It has just occurred to me that if you can make or get hold of a switched
attenuator to stick in between the antenna and the input socket of your
remote receiver, you can make very accurate measurements indeed. I am
thinking of the type with 8 or 10 switches. The first switch gives 1dB of
attenuation, the next 2dB, 4dB, 8dB, and so on. So long as you have some
sort of signal strength meter you can monitor on the receiver, you just
switch in enough attenuation to give the same meter reading at each test
location and record how much attenuation you have switched in at that point.
The more attenuation, the better the received signal. That will allow you to
determine relative signal strength to within 1dB which is going to be good
enough for your purposes. The attenuator can be used for all kinds of
projects, so it might be worth taking the time to build one irrespective of
what you end up using for a signal source. The usual Google search will turn
up construction details, just resistors and switches in a screened box with
some PCB offcuts or copper foil to provide internal screening between each
section.

I agree with Hal, the MFJ kit is jolly good for the price. It does what it
says on the box, just don't expect miracles.

Mike G0ULI