Mixing Product? 1760 AM 2343 UTC 22 Jan 2014

[ChrisSmolinski]

Noticed this while checking the extended band. I have a carrier that will appear on 1760 for a minute or so at a time, with what sounds like the audio of two stations. So perhaps some sort of mixing product? The interesting thing is that it doesn't fade out, it completely drops out, then comes back again full strength.

[Kilokat7]

I've got it here too, but very weak.  I can tell there's audio there at times, but it's much too weak to understand any of it.  Sounds like a harmonic or mixing product.  Check for parallels on 880 if you have good enough audio.

[ChrisSmolinski]

Thanks for the suggestion Kilokat7, I will do that.  This reminds me of the station I coped on 6850: http://www.hfunderground.com/board/index.php/topic,14877.0.html which BOR says is a mixing product between CBC 690 and 6160, in how the carrier and audio instantly appear and disappear, vs fading in and out.

[atrainradio]

Chris and Kilokat- I always get a harmonic on 150 kHz of 950 WKDN an one other station. I forget the other station, but not only that, I get a harmonic somtimes on 2420 kHz of the 50kw flamethrower 1210 WPHT. It is really bad sometimes becuase its transmitting antenna is but just 1 mile away from me!! I can actually see the tower from the back window of my house!

[cmradio]

I always get a harmonic on 150 kHz of 950 WKDN an one other station.

That is likely a receiver image.

...I get a harmonic somtimes on 2420 kHz of the 50kw flamethrower 1210 WPHT. It is really bad sometimes becuase its transmitting antenna is but just 1 mile away from me!! I can actually see the tower from the back window of my house!

Their 2nd may far exceed FCC recommendations for surpression and spectral purity, but you're just so close you'll hear it anyway. Had that living right next to military transmitters of CKN... their 2H was -90dB down, but when you're belting out a million watts....

Peace!

[atrainradio]

What do you mean by a reciever image?
And sheesh a million watts?? Thats enough to start hearing it in the metal bed springs like I've heard has happend to some!

[cmradio]

What do you mean by a reciever image?

All superheterodyne receivers fall victim to image response.

The I.F. frequency in generated by either the sum or difference of the received signal of the local oscillator. When the unwanted mathematical relation (sum or difference) is demodulated, that becomes the "image".

And sheesh a million watts?? Thats enough to start hearing it in the metal bed springs like I've heard has happend to some!

Our neighbourhood had "singing" gutters when two gutter sections corroded and made a diode. We fixed it with a cordless drill and rivets

Peace!