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Transceiver signal interference

I have a Yaesu FT-840 Tranceiver that seems to have AC line interference imposed on its output signal. I need a solution! Can you help me?

Dave

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You have an oscillsocope to see the
signal imposed on the output signal.or
are you talking about sound(hum)
AC line interference is usually
power supply filter caps or
output filter caps or bad
ground (ground loop)
1 check grounds
2.check for bad antenna cable
3.check power & output amp filter capacitors

Posted on Dec 23, 2007

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The FT-840 uses a die-cast RF power amp with thermally switched fan to ensure full power output (up to 100 watts). The digitally synthesized local signals ensure clean, low-noise transmitter output on all HF amateur band. There might be no AC line interference. it has strong Rf output. any AC line intersect does not affect its radio performance. Check and adjust RF power so to maintain proper output. some times more RF power generated at the output may cause interference. adjust Rf power..Even some unfiltered Noise getting the other end of the end may calso cause interference. Check for any Ripple voltages present at the output. Contact authorised service station for further Rectification. thank you shanth

Posted on Dec 23, 2007

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