Cobra 148 gtl rx/tx ok but hissing noise on background

[manuelflo]

Cobra 148 gtl rx/tx ok but problem is a constant tone noise on background with rf control down . Volume control can control constant tone noise. Sqwelch cut tone noise... mic ok. Only happens on ssb am ok. Thanks in advance for any help

 

[BayouRadioAmplifier]

so nobody replied here to this one. ? ? ?

are you new to SSB mode?

go to ch. 38 LSB during the day, and are
you hearing the madness there?
test your receiver there.

some hiss is normal in SSB receive.

what version 148 radio do you have?
the tag on the back of radio.?

Red China, Free China, Flip, made?

 

[nomadradio]

constant tone noise

When I see the word "tone" I think a musical note, like from a flute or a guitar string. I think what you meant was a hiss, like the sound of compressed air coming from a leaky hose.

The "hiss" will always be louder on sideband modes USB and LSB, fainter on AM when the antenna is not connected. The difference is not so much when the antenna is connected.

73