VK Logger Ham Radio Forum Archive

Not sure if this is the right place to put this
I am receiving a signal on 471mhz sounds like telemetry and after much research, in fact about 2 minutes, I discovered that it is possible that it may be telemetry from the town water supply monitoring system. But I don't want to leave it at that I would like to decode what's being transmitted even if it's only once. Any ideas what software I could use to decode? I have tried Fldigi but all I get is garbage on screen, but maybe that's all I will get anyway

Adrian

Do an ACMA database search on the exact frequency and area. Do you live close to a golf course? They use a lot of telemetry for watering systems, typically the Toro and Rainbird systems. Pretty easy to track.


Sent from my iPad using Tapatalk

Hi Adrian,

From one Adrian to another, I suppose you mean telemetry on 471MHz. The unit for Frequency is Hz, named after Mr. Heinrich Hertz.. All units named after people have an upper case first letter. The prefix for Mega is a upper case "M". The prefix for milli is lower case "m". So 471mHz is 0.471 hertz.

All this info is on the web:

http://en.wikipedia.org/wiki/Internatio ... m_of_Units

73, Adrian, VK4OX.

(c/o Pedant's Corner)

OK stand corrected post was sent from my iPhone which didn't autocorrect for the first time. MHz not mhz
I live about 1km as the crow flies from the town water tank signal is strong


Adrian

try listening to a few of the samples here to see if you can ID it.

http://www.sigidwiki.com/wiki/Signal_Id ... tion_Guide

or

http://www.nonstopsystems.com/radio/radio-sounds.html

VK4KL wrote:Not sure if this is the right place to put this
I am receiving a signal on 471mhz sounds like telemetry and after much research, in fact about 2 minutes, I discovered that it is possible that it may be telemetry from the town water supply monitoring system. But I don't want to leave it at that I would like to decode what's being transmitted even if it's only once. Any ideas what software I could use to decode? I have tried Fldigi but all I get is garbage on screen, but maybe that's all I will get anyway

Adrian

Quite possibly BELL 300bps or 1200bps FSK modulation

This could also be low powered devices like crane controllers, as well as telemetry.
There is provision for licenced 10mW controllers and up to 5W for telemetry. I have seen plenty of gear, typically 1200bd using Bell 202 tones or similar running things like river/water level sensors, often using the 5W Maxon data radios.

To decode, you could try some of the Amateur software.

I have tried all modes in FlDigi with no luck just garbage on the screen but like I said it's probably all I will get

Adrian

Adrian
A few questions...

Is it a continuous signal?
Does it come in bursts (packets)?
If it is in bursts, did you try decoding with Pocsag (IIRC)? It could be a paging system signals, or similar...
see here... http://www.discriminator.nl/pdw/index-en.html

73 Bruce VK2EM

Sample of telemetry
Comes in bursts sometimes 1 every 60 seconds or so sometimes 2-3 every 5 seconds
Sometimes I can hear a second burst but from a repeater(?) much lower in strength.
will have a look at other software to try decoding

Adrian

VK4KL wrote:Sample of telemetry
Comes in bursts sometimes 1 every 60 seconds or so sometimes 2-3 every 5 seconds
Sometimes I can hear a second burst but from a repeater(?) much lower in strength.
will have a look at other software to try decoding

Adrian

I seem to recall for the deep dark past the some of those systems used a standard packet TNC