Rangemaster HAMILTON AM1000 - Manual (Page 15)

The transmitter should sound as loud as others on the dial, if it doesn’t there is a problem. It may be an audio
impedance mismatch, or the level may need to be turned up. If the audio level isn’t high enough you won’t get
good range, audio is a gate on the power, keep your audio turned up as high as you can.
We have found the most common cause of low range is the audio setup, even more common then grounding
problems. Not enough audio power (volume) and/or an impedance mismatch. If you are using an 8 ohm (low
impedance) output which would be a headphone or speaker output you may need to find a way to use a line level
output. An impedance mismatch will lower the audio level and reduce the fidelity, and may cause distortion. If
you have a line out type source it needs to go to the high impedance jack on your audio adapter. In either case if
you can’t get the audio loud enough so it is as loud as other stations in your area without distortion then there is a
problem in the audio chain.
To get more Range:
Try to locate the transmitter near something that will reradiate the RF energy such as high tension power lines.
The signal will tend to follow lakes and rivers. Use as high a audio level as you can. Get the unit as high
as you can but not so high you can’t safely get to it to tune it.
Most of the time low range is a problem with the ground. (see the troubleshooting manual) if you can remove your
ground and not see a difference in the tune voltage or range then the ground is likely the problem. If when you are
tuning the “Cap Tune” you don’t see much movement of the meter, then you probably have a poor ground.
Placement of the Transmitter is important, keep it away from metal and other objects.
One way to look at it is that the antenna is the (plus) of the battery and the ground is the (negative) of the battery.
To get good radio current flow (from the antenna to the ground) you need the antenna to be placed so that the radio
waves can flow out from it without being blocked. And the ground needs to have low resistance.
If when you are standing at the antenna you have a high wall to the North for example, you probably will not get
good range in that direction. Distant objects will have little effect though if they are higher, if the transmitter was
on a one story house and there was a two story house 200 meters away, then the signal would not be affected
much.
If there is a lot of electrical noise in the area you may have range problems. You can listen to a test radio and usu-
ally tell how quiet the band is, listen for a quiet “hiss”. If you hear nasty hum, sparking, ect , then that is a indica-
tion of high noise.
It will be harder to get good range in metro city areas, as they are usually noisy with radio interference.
Watch out for high power microwaves, they can blank out the AM dial. If there is a radar dish nearby you can for-
get good AM radio reception.
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See trouble shooting manual for more troubleshooting information!