HELP ME PLEASE !!! Trouble with FM PRO I (humm noise)

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ssi
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HELP ME PLEASE !!! Trouble with FM PRO I (humm noise)

Post by ssi »

Hello !!!

I'm buy FIVE FM pro I but I have a problem !

I create DIPOLE 1/4 wave antenna with coaxial cable RG8.

When I put (The OUTPUT Gain at minimum) all it's okay.

When I put the Output GAIN at 1/4 or 1/2 power or Full power I have a VERY BIG Hummm NOISE in the sound :( Why ???

And I have a BUZZ sound on my transmitter !!!

I use switching power supply 15 VDC

THANKS IN ADVANCE FOR YOUR ANSWER !!!

Nick Lavoie
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pcs
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Post by pcs »

What is FIVE FM pro I ?
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
ssi
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WHAT !!! ???

Post by ssi »

I buy (5X) MAX PRO I - 7W

YOU UNDERSTAND NOW !!!
HELLO :) !!!
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pcs
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Post by pcs »

The brum problems are usually when:

1.) MAX PRO I is not in a metal enclosure.

2.) Your SWR is not that good and you have RF radiation
on the outer shell of your coax.

3.) Antenna too close to transmitter and audio setup.

4.) Antenna / Coax too close to power supply.

5.) Power supply not RF shielded/blocked. Try using battery
and see if it makes any difference.

6.) Ground loops with your audio stuff. Disconnect audio jack,
if the hum is gone than you've got a problem with your audio setup.
Best regards,
Marko - PCS Electronics
--------------------------------------------------------
Turn your PC into a FM radio station!
http://www.pcs-electronics.com
fax +386 4 2316 128
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