Hi folks,
First post here.
I'm currently working on a little project of my own. It's a communications system,
I have a Canford audio comms box linked to a baofeng 888s two way radio. By turning on the
VOX system on the radio and connecting the output side of the cans headset, via a noise gate
to the input side of the radio, I have managed to create a rudimentary (half duplex) wireless comms system.
The whole system is boxed up neatly and the radio is run from the 20v power source through this:
http://www.amazon.co.uk/DC--DC-Conv...=1425573897&sr=8-4&keywords=dc+buck+converter
Set to 3.5v
As I said, the whole function works rather well, the radio talks to the comms system without a problem,
the issue I have is that when I talk to the radio from the comms, Although I can hear voice I'm getting lots of 'pulsating/modulating' interference.
I have solved the issue part way by turning off the display on the buck converter. When this is turned off
a lot of the noise goes away, However there is still some about and I can't locate it. It becomes an issue
because once it starts making noise, not only is the output signal modulated, but some kind of feedback loop
is created and it locks the noise gate open meaning the VOX on the radio doesn't stop transmitting.
I have tried resistors and capacitors and diodes of various values in series and parallel with the output signal path (to the gate) and nothing seems to help. Everything is grounded properly and if I pull power from
the buck and use the cans box on it's own the noise is completely gone so I'm pretty sure it's interference from the buck.
I've had a look around the net and can't really find anything specific enough for my needs
(now someone will post a generic link identifying my problem and a simple way to fix it)
Please help...
Thanks in advance!
First post here.
I'm currently working on a little project of my own. It's a communications system,
I have a Canford audio comms box linked to a baofeng 888s two way radio. By turning on the
VOX system on the radio and connecting the output side of the cans headset, via a noise gate
to the input side of the radio, I have managed to create a rudimentary (half duplex) wireless comms system.
The whole system is boxed up neatly and the radio is run from the 20v power source through this:
http://www.amazon.co.uk/DC--DC-Conv...=1425573897&sr=8-4&keywords=dc+buck+converter
Set to 3.5v
As I said, the whole function works rather well, the radio talks to the comms system without a problem,
the issue I have is that when I talk to the radio from the comms, Although I can hear voice I'm getting lots of 'pulsating/modulating' interference.
I have solved the issue part way by turning off the display on the buck converter. When this is turned off
a lot of the noise goes away, However there is still some about and I can't locate it. It becomes an issue
because once it starts making noise, not only is the output signal modulated, but some kind of feedback loop
is created and it locks the noise gate open meaning the VOX on the radio doesn't stop transmitting.
I have tried resistors and capacitors and diodes of various values in series and parallel with the output signal path (to the gate) and nothing seems to help. Everything is grounded properly and if I pull power from
the buck and use the cans box on it's own the noise is completely gone so I'm pretty sure it's interference from the buck.
I've had a look around the net and can't really find anything specific enough for my needs
(now someone will post a generic link identifying my problem and a simple way to fix it)
Please help...
Thanks in advance!