I believe I have it installed correctly, it gets fm radio just fine. I am not a mile from the police station and get nothing. I know that they are broadcasting on 154.280 because I hear it with my scanner. What could I be doing wrong?
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Have you changed the setting in the radio button section? Is it set to NFM?
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No, I thought it was supposed to be wide. I'll try that and get back to you....
br0adband
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Probably 98% of stuff above 25 MHz is done with Narrow FM except for the tiny 10 MHz window where FM radio sits between 88 and 108 MHz (that's Wideband FM with typical bandwidth of 180 kHz to get the whole signal in), and of course there's AM between 116 and 136-138 for civilian Air traffic then 225 to 380-385 MHz for military Air traffic - those are big chunks of the actual frequency space available, yes, but the actual amount of traffic in those areas is like a drop in the bucket in terms of monitoring. The 420-450 MHz Ham area is a huge chunk of spectrum with very little actual use, then 450 to 470 MHz for primarily business and commercial services with some police/fire/EMS/etc sprinkled in their now and again.
Then you've got content, still NFM based, in the 760 to 780 MHz range nowadays as well as traditional 851 to 861 MHz (the 861 to 868 part got swallowed up in the rebanding process, and lastly the 935-941 area for more NFM traffic (business use mostly depending on the area.
Simplest thing to remember: if it talks in the air, expect it to be AM - if it talks on the ground, expect it to be Narrow FM aka NFM, and it music or "radio" concerned it's Wideband FM aka WFM, and anything down under about 29 MHz will means shortwave/longwave/AM broadcast radio etc will be AM almost exclusively with Upper and Lower Sideband use as people wish.
As for why you're not hearing anything on something that geographically close with the RTL stick and you can with an actual scanner could be related to overload on the RTL (they're very susceptible to it in strong signals areas) or potentially desense where the strength of the signal is simply "too much". Try tuning the frequency with the signal gain at 0 on the gain slider (seriously) and then ease it across till you see something on the spectrum/waterfull. If necessary you might consider disconnecting the antenna entirely (or detach it from the base of whatever is using it and then make short use of the antenna cable itself as your antenna temporarily).
If the scanner gets something on that frequency and an RTL stick doesn't, then there's something going on with the RTL or the settings in use controlling it.
Then you've got content, still NFM based, in the 760 to 780 MHz range nowadays as well as traditional 851 to 861 MHz (the 861 to 868 part got swallowed up in the rebanding process, and lastly the 935-941 area for more NFM traffic (business use mostly depending on the area.
Simplest thing to remember: if it talks in the air, expect it to be AM - if it talks on the ground, expect it to be Narrow FM aka NFM, and it music or "radio" concerned it's Wideband FM aka WFM, and anything down under about 29 MHz will means shortwave/longwave/AM broadcast radio etc will be AM almost exclusively with Upper and Lower Sideband use as people wish.
As for why you're not hearing anything on something that geographically close with the RTL stick and you can with an actual scanner could be related to overload on the RTL (they're very susceptible to it in strong signals areas) or potentially desense where the strength of the signal is simply "too much". Try tuning the frequency with the signal gain at 0 on the gain slider (seriously) and then ease it across till you see something on the spectrum/waterfull. If necessary you might consider disconnecting the antenna entirely (or detach it from the base of whatever is using it and then make short use of the antenna cable itself as your antenna temporarily).
If the scanner gets something on that frequency and an RTL stick doesn't, then there's something going on with the RTL or the settings in use controlling it.
M105
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Check your RF Gain. I usually just check the Tuner AGC box.
Check your PPM setting on the dongle. A mis-tuned dongle will often work on broadcast WFM but will totally miss a NFM signal. You can use your local NOAA weather station to calibrate the PPM setting.
Check your squelch. Try turning off the squelch until you get the issue worked out.
Check your PPM setting on the dongle. A mis-tuned dongle will often work on broadcast WFM but will totally miss a NFM signal. You can use your local NOAA weather station to calibrate the PPM setting.
Check your squelch. Try turning off the squelch until you get the issue worked out.
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Thank you both for the very informative posts, helpful both. I will have to play with the ppm as I cannot hear the local noaa weather channel either. I was able to hear the fire channel switching to nfm.
I'm going to buy a discone soon, but for now I have jerry-rigged a cb antenna outside.
Also, a point in the right direction for decoding the mswin in Mississippi would be helpfull...
You have just described a perfect recipe for INCREASING overload as Br0adband mentioned. More antenna is not better if overload is your problem. Better to diagnose the problem before implementing a solution :wink:
Thanks for that helpful info. That was a temporary solution as a means to an end. Ive ordered a discone and coax. It will be upabout 20 feet.
I will, however; reiterate my query as to decoding the mswin in MS.....
I will, however; reiterate my query as to decoding the mswin in MS.....
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