PSR500/PSR600: heard on other frequency

[scanmanmi]

My scanner stopped at 257.05 on some muffled noises on AM mode. I found it was a grabled 94.5 FM. I subtracted them and came up with 162.55. There is a nearby weather station on 162.525 though. I have heard voices on some wierd freqs like 166 or 171 or something like that. What up?

 

[ScannerSK]

My scanner stopped at 257.05 on some muffled noises on AM mode. I found it was a grabled 94.5 FM. I subtracted them and came up with 162.55. There is a nearby weather station on 162.525 though. I have heard voices on some wierd freqs like 166 or 171 or something like that. What up?

That sounds like intermodulation to me. The following article explains it somewhat:
Wiki on Intermodulation

Shawn

 

[Ubbe]

You could probably solve it by using a FM trap filter. If you use the BNC rubber antenna you could look out for fliters that has BNC male-female, like the super expensive one from Stridsberg.

/Ubbe

 

[krokus]

My scanner stopped at 257.05 on some muffled noises on AM mode. I found it was a grabled 94.5 FM. I subtracted them and came up with 162.55. There is a nearby weather station on 162.525 though. I have heard voices on some wierd freqs like 166 or 171 or something like that. What up?

Most radios use 10.7 MHz as an IF, which gives you a 21.4 MHz offest image possibility, too. Is there a military user, on 141.15 MHz, nearby?

Sent via Tapatalk

 

[737mech]

Plus one FM Trap

I think you will really really like your scanner if you decide to install an fm trap. Good ones are available from Dale at Parelectronics or you can try a cheap one from Radioshack. Try it, you will finally hear what you've been missing out on.

 

[vagrant]

I am a fan of PAR filters and and have four different ones. I also use a Radio Shack FM filter and this particular combined notch filter that is for AM & FM. HPN-30118 Combined Notch Filter | Scanner Master

In particular, I use that combined notch filter on the scanner in my vehicle. The filters I use are worth every penny and resolve RFI issues I have, some of which I cause myself.

 

[scanmanmi]

I will get a trap. I am starting to listen to Air band and was wondering if they attenuate those freq inadvertently.

 

[Ubbe]

I will get a trap. I am starting to listen to Air band and was wondering if they attenuate those freq inadvertently.

Yes, they do.

You have to look at filters specificly made for airband monitoring. They usually trim the attenuation curve 10MHz lower or do not attenuate as deep in the FM broadcast range.

/Ubbe