Choppy audio, signal strength issue?
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TOPIC: Choppy audio, signal strength issue?

Re: Choppy audio, signal strength issue? 29 Apr 2012 15:16 #9448

  • Ohio-user
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Did you ever try with the squelch set lower as I suggested earlier? You said midway which is way too high.

Other than that it just sounds like weak signal.

Re: Choppy audio, signal strength issue? 22 Oct 2012 20:19 #10355

  • st-bob
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"try throwing some money at it randomly", which is how I interpret that answer.
Not at all... You just don't understand what's going on and are trying to blame the radio for something that's not the radio's fault.
Bob Peloquin - KB1VUA
RR db admin (Massachusetts), USA
Scanner/GPS/Ham Radio enthusiast

Re: Choppy audio, signal strength issue? 22 Oct 2012 21:02 #10357

  • Kegan36604
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st-bob wrote:
"try throwing some money at it randomly", which is how I interpret that answer.
Not at all... You just don't understand what's going on and are trying to blame the radio for something that's not the radio's fault.


I don't understand what's going on? Enlighten me. I'm listening. Not the radio's fault? Then what is at fault? I'm anxious to hear your diagnosis.

Not the radio's fault? Perhaps, but when the device performs a certain way, and then performs totally different - and the location of the radio, the system software of the HP, the settings on the HP, the freq's monitored, the provider of the feed (agencies) do not change, that pretty much leaves the radio. Is there a more obvious variable?

And yes, I stand by my remark that try a new antenna or send it in and pay a bench charge while the tech is figuratively shrugging his shoulders, is a 'throw some money at it' response. Seriously though, if you know what's going on with it, I'd appreciate your advice.

Re: Choppy audio, signal strength issue? 22 Oct 2012 21:49 #10358

  • st-bob
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OK, OK. Don't get all upset with me. Digital is way different than analog. It is subject to many more problems with reception than the same system would be if it was analog. Do you remember back when we all watched TV on outdoor antennas? Do you remember what happened when an airplane flew over? The picture faded and ghosted as reflections of the signal came and went even though the TV or antenna was never moved.

Same thing can happen today but with different results. There's no "fading" or "ghosting" with digital signals. They're either being decoded with adequate error correction or they're not. You either get perfect (or nearly so) reception or you get nothing. When this comes and goes it's probably due to traffic passing by or atmospheric conditions. The signal strength has little to do with whether you receive a error-free digital stream or not. You could have a really strong signal but reflections could be making the signal have multi-path which is what caused the shadows and ghosts on your old TV. In the digital age, this increases the bit error rate (BER). Digital TV and two-way radios use a technique called forward error correction to repair the missing data in the packets of digital information. Forward error correction (FEC) can only correct the lost bits to a certain extent but when too many errors occur then all bets are off. The radio will go silent for short periods or "stutter" and occasionally make loud squawks, braapps etc. etc. when on the edge of reception. That's just the nature of digital radio.

Now if you had the police department's handheld radio (which costs several thousand dollars) instead of a 500 dollar scanner, you might get better reception and you might not. Expensive commercial radios have proprietary algorithms in them to help with high bit error rates. Sometimes they work better than commercial-quality scanners for many reasons. A scanner has such a wide open front-end in order to receive across so many bands that it's often subject to intermodulation distortion from paging systems etc. This can momentarily desensitize the receiver and increase the BER on digital signals. Since the channel it's locked on is digital, you wouldn't hear the overpowering signal - you'd just lose reception altogether.

When Uniden says you may need an outside antenna they're telling you the truth but not being all that helpful. You may only need to find out whether or not you can benefit from an outside antenna. You might need a notch filter to reduce or eliminate a problem paging transmitter nearby. You should scan the common pager frequencies in the 150 to 160 MHz range and in the UHF 900 MHz area for overpowering signals. I have to use a notch filter here since I'm within 2 miles of a 500 watt pager system in the 158 MHz area or it'll blot out my reception across a wide range of frequencies on both my HomePatrol and Radio Shack (GRE) scanners.

Try this. Take the scanner to the highest location in the house and see if it improves. If not, take it outside and get to a higher location. If the problem has been cured, you have a reception problem at your desired location of use. It may not be a signal 'strength' problem. It may be a multi-path problem. This can be fixed by using a highly directional antenna such as a yagi tuned for the desired frequency or a wider-band (but less directional) log-periodic antenna. Turning the antenna till the reception is consistently perfect is the only way you'll know you've cancelled the multi-path reception.

If it's desensitization caused by a nearby intermittently transmitting pager or cellular PCS site, you're going to need a notch filter and maybe also a directional antenna turned 90 degrees to the offending strong station.

Keep in mind that you will only be fixing the problem for ONE CHANNEL or one trunked system using a single site with a directional antenna.

In one case, it could be the antenna. The stock antennas are known to be a weakness in the HomePatrol. It might be the antenna but the only way you'll know is to try another stock one or a different brand such as the Watson WSMA-889 or the Diamond SRH789 which I use occasionally (I mostly use a discone on the house's roof or a mobile multi-band whip antenna on the car).

If that doesn't convince you it's not always the radio - I don't know what will. You act like you think because it cost $500 it should work way better than a $30 analog scanner. That's unrealistic. Digital radio is digital radio. It has different problems than analog and different solutions. You need to do what you must to fix the problems even when you have no way of telling if those problems are really present or not at your location. It would be very expensive to own the equipment necessary to diagnose the problem. It's much cheaper to try something that's been known to help. I doubt you'd want to spend several thousand dollars on spectrum analyzers and digital service monitors...
Bob Peloquin - KB1VUA
RR db admin (Massachusetts), USA
Scanner/GPS/Ham Radio enthusiast
Last Edit: 22 Oct 2012 22:00 by st-bob.

Re: Choppy audio, signal strength issue? 27 Oct 2012 16:30 #10401

  • JD3
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If you are using the supplied "rubber duck" antenna you will have a much stronger signal strength with some sort of outside antenna.

I leave near a transmission tower (within 2-3 miles) and had poor reception, too.
The frequencies used in my area are in the 150mhz range, and I used an extra 2m ham radio antenna mounted to the roof.
I get 100% signal strength and the signal is WAY better, but once in a great while I still get some digital garbage sounds.

You will get a better signal strength, but you still may get some choppy audio.

I still would recommend an exterior antenna. Make sure the type you choose will work with the frequencies used in your area.
If you need help with that, just ask on the forum. Many users here are willing :)
Last Edit: 27 Oct 2012 16:30 by JD3.
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