SSB Noise / Whining

[Ringworm]

Ok, newbie ssb question here.

Galaxy 95T, Wilson 1000 mag mount (no coiled coax) Antenna tuned to 11 meter. Mobile.

What is that whistling or whining sound when on ssb? It goes from a higher to lower pitch when using the clarifier, and it almost disrupts the rx, get's in the way of hearing what's going on. It doesn't happen all the time, but most of the time. Sometimes it's louder, and sometimes quiet and distant.

I did notice it'll come on, sometimes, when people on the other end are speaking.

Is it my tuning habits, something going on with the radio, normal?

Thanks your the help.

 

[Captain Kilowatt]

Sounds like you are picking up an AM signal while receiving on SSB. It is called heterodyning and is the result of two signals mixing together. In this case the two signals are the AM carrier of the station you are hearing and the carrier injection oscillator of the SSB radio you are using.Since SSB has no carrier the receiver must reinject a carrier in order to decode the audio. Next time you hear it switch to AM mode and see if you hear anyone clearly.

 

[midnight special]

have you got your anl/nb turned on?

 

[Ringworm]

The anl/nb is turned on. I have switched the radio to AM while on SSB and listening to the "sound", AND hearing someone speaking: When switching to AM the "sound" and the people speaking (receive?) go away and don't seem to be on AM.

I'm going to try to record what's happening, post it on YouTube, and i'll post the link here.

 

[M0GVZ]

The anl/nb is turned on.

Turn it off, it ruins the selectivity.

 

[Ringworm]

Turn it off, it ruins the selectivity.

Oh, ok will do, had no idea. Thank you.

 

[n8fgb]

First thing to do is disconnect the antenna. If the noise dose no go away, it is coming from your car. Might alternator whine.
Rich

 

[Captain Kilowatt]

Odd that the OP said it comes on when "people on the other end are talking". Alternator whine should be present with or without a signal present and in AM mode as well as SSB. Not sure but IIRC it doesn't change pitch when the clarifier is adjusted.

 

[Moleculo]

Definately a heterodyne. It goes with the territory on these frequencies.

 

[C2]

We need the youtube so we can stop guessing. a couple of my radios have drifting birdies