|
This page contains a few quick pointers to HF use; lessons that some VKS-737 subscribers have learned
and want to share.
(Please use the navigator bar below to skip UP and DOWN the page).
Navigator: [ HF Power Supply ]
[ Radio Checks ] [ Garbled
Transmission ]
Interference (natural)
HF always has some natural background interference (known as hash; or "static"
to the uninitiated).
To reduce the level of this interference, you could try other frequencies or try at a
different time of the day, but it will always be there to some degree.
A tip for better communications through strong hash
is to turn your incoming speaker volume way down low. Then put
your ear close to the speaker. At low speaker volume, hash is
poorly reproduced while voice gets much better treatment.
Your incoming signal could be much easier to understand !
Navigator: [ Interference ] [ Radio
Checks ] [ Garbled Transmission ]
HF Power supply
( to be written )
Navigator: [ Interference ] [
HF Power Supply ] [ Garbled Transmission ]
Radio Checks, with a Network base
Mobile stations are often heard asking a base station for
radio check. Base operators don't mind this if time permits, because
it is useful practice for mobiles (effective communications, when
in remote areas, can be vital).
If you need advice on your radio's performance, you can call in
and request a check, but this should be when traffic levels on
the sched are light. If you can't find a convenient slot, you
could ask for a response from any mobile, in "off sched"
times. VKS-737 subscribers on air at the time are usually quite happy to respond.
Performance factors for radio checks are:
A. Readability ( rated as 1 - 5 )
1 - Unreadable
2 - Barely readable (only occasional words perceptible).
3 - Readable with extreme difficulty (some content missed).
4 - Readable with practically no difficulty (maybe occasional words missed).
5 - Readable with no difficulty (100% copy).
B. Signal Strength ( also rated as 1 - 5 )
1 - Very quiet, (very low level) barely audible.
2 - Quiet signal, (low level) audible only with considerable difficulty.
3 - Moderately loud (fairly strong signal) fairly audible above
background noise.
4 - Loud Signal (Strong signal) comfortable audio level, almost
completely over-riding background noise.
5 - Very Loud (very strong signal) As if speaking face to face,
completely masking background noise level.
Notes:
1. Amateur radio operators have a more technical system of rating
- we use the 5 X 5 for simplicity.
2. Operators may not have instrumentation available; they will
provide their best estimate of the signal factors
Navigator: [ HF Power Supply ] [ Radio
Checks ] [ Garbled Transmission ] [
Interference ]
Garbled Transmission
( to be written )
All contributions welcomed [
Network Staff ]
|