Looking for better reception

[Kito]

I have a Radio Shack Pro95 that is 8 years old and works great ( I tried bying a Pro 400 series and returned it as the Pro 95 had better reception) I have tried all the attachable ant. that RS carries and am just not able to pick up the city I am trying to get. It does sit roughly 10-15 miles away from my house. I am willing to put some money into a new scanner so that I can get better reception I am just not sure in what direction to go.

Right now the police dept I am trying to get is not digital but they have plans to go digital this summer at some point. I cant pick up the dept now but there is a lot of static Also if there is talking for more than 3 seconds or so the sound smooths out some.

I an really green with all this and am not sure if there is help for my Pro 95 or if I should just get something new. And if I am going in the new direction what I should look at that can pull in a signal from about 15 miles away.

Thanks so much for any advice.

 

[ka3jjz]

It would be most helpful if we knew what city in Missouri you're talking about here, and where you are. 15 miles on 800 should be doable - unless you've got a lot of terrain type issues (lots of hills, trees, etc.) which can hamper 800. An outdoor antenna, nice and high and away from obstructions would seem to be the answer here. When digital comes around, that poor a signal might not allow reception at all. Then an outdoor antenna would be almost a necessity. Are you geographically low in respect to the city? Sometimes that can result in a hole where reception is very difficult.

If you're near a lot of NexHell towers, pagers and so forth, you could be experiencing some desensing issues - essentially, your scanners are being overloaded to the point that they're locking on to another signal within a certain passband, and not necessarily the ones you want to hear. A better antenna might not be enough in this case without some directionality (in other words, a small beam - which at 800 is quite tiny) or perhaps adding some filtering.

There is also the possibility that the city is concentrating its coverage to within its borders - the city of Philadelphia does this, and it makes hearing their trunk quite difficult when you're out in the suburbs. It would seem the newly-reconfigured Baltimore city system also has this issue, among many others.

However this is all a shot in the dark without some more information

best regards..Mike

 

[Kito]

I am in Springfield and I am trying to pick up Nixa and Christian County. I am not near a cell tower that I am aware of but there are plenty between here and there.

 

[N8IAA]

Right now the police dept I am trying to get is not digital but they have plans to go digital this summer at some point. I cant pick up the dept now but there is a lot of static Also if there is talking for more than 3 seconds or so the sound smooths out some.

I'm going to take a guess in the 9 years you've owned the 95, that the antenna has been taken on and off a considerable amount of times. The BNC connector maybe getting worn out, or, even some of the electronics in the radio might be getting old. Their older VHF system could be one of the reasons for them to be going digital. Best bet is to get one of the RS scanners on sale. Either the 106, or 197. The 106 is a handheld like the 95. That way, you are covered listening to the county and city while they are still on VHF and after their transition to 800. You'll also be able to listen to the Missouri statewide system if it ever grows.
HTH,
Larry

 

[benbenrf]

You’ve got a number of options

1) Antenna choice and setup - a decent set of ears (antenna) has to be top of your list of options if you are staying with the same scanner/receiver – and now is probably the time to consider a VHF/UHF broadband LPDA (Log Periodic Dipole Array) that is going to offer you coverage from, say, 30Mhz – 1100Mhz or whatever bandwidth you desire. Why an LPDA?

For a number of reasons: they are, as I am sure you know, a directional antenna type, and as you have pointed out that you have a defined direction for reception (the city), an LPDA is going to offer a significant improvement in SNR (Signal to Noise Ratio). Depending on the receiver architecture, improvements in SNR can equal, if not exceed improvements in Gain, but receiver architecture aside, the improvement in SNR is never-the-less going to be real-world realisable i.e. forget any exact dB measurement, or FBR measurment ..… or however else one wishes to define atheimprovement, the combination of improvement in SNR, coupled with the now greater antenna Gain and improved Front Back Ratio .... etc etc ...... is all going to add up to presenting your receiver's front end with a stronger and cleaner signal, which in turn is going to result in "stronger" and cleaner demodulated audio.

2) Coax – you don’t say how long the coax run is between the antenna and your receiver, nor do you say what coax you are currently using? It may be only 20 feet or so in which case the benefits versus the money spent may well turn out to be pretty small nand ot really worth the effort (?). However, if your coax run is 30’ – 50’ or more, then coax choice now starts to significantly impact signal strength arriving at a receivers' input socket - and the greater this "impact" is the higher the freq you are monitoring. Give some thought to changing the coax. Do some "length versus loss "calc's for the coax you are using, versus anything else within your budget.

3) Preamp – I left preamp to last: it is in my personal opinion the last option you want to implement – if you are using an omni-directional antenna. that is. Preamps on omni-directional antennas not only amplify the signal you want to listen too, they also amplify everything else in the selected bandwidth i.e. your SNR stays the same – and to the receiver front-end, things appear much the same. Thats' not the case however using preamps with directional antennas. The benefits realised with a directional antenna, as described in 1), can often be enhanced with correct/proper amplification - so don;t negate a preamp altogether: in the right place they can offer a realisable and hearable improvement.


...... and the last option: invest in a better receiver – and as I think I have said before on this forum elsewhere, don’t overlook a used pro unit like WJ, IZT, Racal or similar rtype eceiver……. you’re going to get much more/better performance ( exponentially better) Dollar for Dollar buying a used Watkins Johnson 8617 (with the right options installed) or similar, on eBay, than you will spending equal or 2 to 3 x’s as much on a new modern off-the-shelf receiver – the key here, is: do your homework carefully before hand.

Good luck

 

[Kito]

I got the Pro-106 since I would be needing digital in the future. I went ahead and put the same antenna on the scanner (Center-Loaded Telescoping Whip Antenna Center-Loaded Telescoping Whip Antenna - RadioShack.com) and am having the same problems.

I am looking at switching to the Outdoor VHF-Hi/UHF Scanner Antenna ( Outdoor VHF-Hi/UHF Scanner Antenna - RadioShack.com). But I am assuming that will not help with a digital signal... but perhaps the digital signal will be stronger?

 

[benbenrf]

Will the digital be stronger? - maybe, maybe not, but as a rule digital signals occupy a narrower bandwidth (one of the reasons, amongst many others, why digital techniques are used more and more) and narrow bandwidth almost always equates to better receiver sensitivity - so, so long as your receiver has various bandwidths for you to select from, selecting the narrowest one possible for the signal you are listening to should allow you to capatilise on the receiver's inherently better sensitivity as bandwidth setting is reduced - so, yes - you should benefit.

 

[wyomingmedic]

I'm not too sure why folks think going from analog to digital will make the signal stronger. I have heard this a lot lately.

If you are going from analog to digital on the same band, it should be SIMILAR (there are things like conversion gain and such, but for the most part they should be similar).

Your telescopic whip is clearly not enough. Getting the new antenna outside and up 10+ feet in the air would make a world if difference I bet. And there is no reason the antenna would not work on digital. RF is RF, so if the antenna is tuned for the frequency, it does not care if the signal is digital or analog.

WM

 

[Kito]

So I found out that Nixa when they switch will be going to MotoTRBO system so I am pretty sure I need to return the Pro-106 back as it will not work with that system. ?

 

[JRayfield]

That is correct - Christian County, and all agencies in the county, will be switching to a MOTOTRBO system, sometime this summer). There are no scanners on the market, yet, that will decode MOTOTRBO.

John Rayfield, Jr. CETma

So I found out that Nixa when they switch will be going to MotoTRBO system so I am pretty sure I need to return the Pro-106 back as it will not work with that system. ?

 

[Highpockets]

There is a way to monitor MotoTRBO, read this article very carefully, notice operating system, etc.

Digital Speech Decoder (software package) - The RadioReference Wiki

 

[jim202]

Will the digital be stronger? - maybe, maybe not, but as a rule digital signals occupy a narrower bandwidth (one of the reasons, amongst many others, why digital techniques are used more and more) and narrow bandwidth almost always equates to better receiver sensitivity - so, so long as your receiver has various bandwidths for you to select from, selecting the narrowest one possible for the signal you are listening to should allow you to capatilise on the receiver's inherently better sensitivity as bandwidth setting is reduced - so, yes - you should benefit.

I am not sure where you learned radio communications, but it might be a good idea to brush up a little.

Fact one, digital signals do not occupy a narrower bandwidth. In fact, they actually take up more room for the higher data rates to pass more data. Only Motorola will tell you that a digital signal will take up less space. the sales force has been well trained in the best BS that can be had.

In most cases, the digital signal will not go as far as an analog signal and be understood as well. However, some of the real new digital radios do have better error recovery than the older ones and do better than their earlier digital radios at recovering the digital signal from a weak signal. The range is about comperable to an analog signal.

Narrow band on the other hand, due to the signal to noise ratio within the radios tends to not provide the same signal propagation as a normal band width signal we are all use to. There are many studies that have been done to both prove this and to also try to blow this theory out of the water. I would suggest that anyone with questions on the subject talk to an agency and find out first hand what they say. Your probably going to get an answer that will prove they lost coverage for the same power out and the same antenna system being used after they went narrow banded.

 

[LtDoc]

Probably the easiest means of increasing signal strength on VHF/UHF is to get that antenna outside and higher. That height really does make a difference.
What kind of antenna? Preferably one made to receive the desired frequency. Multiband antennas are always going to be 'better' on one of those bands than the others. And then there are directional antennas if what you want to hear is going to be in one general direction. A means of turning that directional antenna is a nice idea too. For the 'average' VHF/UHF directional antenna that rotor doesn't have to be huge. Another alternative is the venerable 'Arm Strong' rotor... turn the thing by hand.
Lots of options, no idea which would be most 'palatable' for you.
- 'Doc

 

[benbenrf]

I'm not too sure why folks think going from analog to digital will make the signal stronger. I have heard this a lot lately.

If you are going from analog to digital on the same band, it should be SIMILAR (there are things like conversion gain and such, but for the most part they should be similar).

Your telescopic whip is clearly not enough. Getting the new antenna outside and up 10+ feet in the air would make a world if difference I bet. And there is no reason the antenna would not work on digital. RF is RF, so if the antenna is tuned for the frequency, it does not care if the signal is digital or analog.

WM

Stronger - who said stronger - the key word/s are narrow bandwidth/improved sensitivity.

 

[benbenrf]

I am not sure where you learned radio communications, but it might be a good idea to brush up a little.

Fact one, digital signals do not occupy a narrower bandwidth. In fact, they actually take up more room for the higher data rates to pass more data. Only Motorola will tell you that a digital signal will take up less space. the sales force has been well trained in the best BS that can be had.

In most cases, the digital signal will not go as far as an analog signal and be understood as well. However, some of the real new digital radios do have better error recovery than the older ones and do better than their earlier digital radios at recovering the digital signal from a weak signal. The range is about comperable to an analog signal.

Narrow band on the other hand, due to the signal to noise ratio within the radios tends to not provide the same signal propagation as a normal band width signal we are all use to. There are many studies that have been done to both prove this and to also try to blow this theory out of the water. I would suggest that anyone with questions on the subject talk to an agency and find out first hand what they say. Your probably going to get an answer that will prove they lost coverage for the same power out and the same antenna system being used after they went narrow banded.

Theres merit to what you have said - but if we are going to get to this level of detail unless the data rate is given, as well as the modulation/encoding scheme and whether or not multiplexing is present, we'll go round in circles i.e. a given bandwidth for a comms channel could be wider or narrower.

What I think it fair to say, is that for a given analogue audio content (i.e. voice) it is possible to carry greater content in digital format for a given bandwidth than it is for analogue format.

With that in mind, it's possible to use a tighter IF setting on the receiver and capitalise on receivers' inherent higher sensitivity at tighter IF bandwidths. That really is the point I wished to make, what of course can throw this all out the window (and often does), is that if a lower Tx/dB level is used (as often is the case) then yes, from a Rx perspective there may well be little, or even no benefit realised.

In all fairness, digital signals can be both narrower or wider than analogue - I think before we start taking delight in correcting one another we need to define a few points e.g. what encoding and modulation scheme do you have in mind, are you reffering to a multiplexed signal, what are the characteristics of the analogue channel one is making this comparison with .....etc ect. Now we can put everything into context.

 

[JRayfield]

Jim, since this thread involved MOTOTRBO, I'll comment on that digital mode specifically.

MOTOTRBO provides better range, in most cases, than analog. It's considerably better than 'wideband' (25 khz), by as much as 3db, and as much as 6db better than 'narrowband' (12.5 khz). I've had discussions regarding this with one of the country's best engineers in radio system engineering and propagation and he has agreed with my findings (in fact, he suggested that there could be a difference of as much as 8db between narrowband analog fm and MOTOTRBO, in some cases).

John Rayfield, Jr. CETma
Motorola 2-Way Radios - Springfield, MO, Implementing New and Emerging Technology

I am not sure where you learned radio communications, but it might be a good idea to brush up a little.

Fact one, digital signals do not occupy a narrower bandwidth. In fact, they actually take up more room for the higher data rates to pass more data. Only Motorola will tell you that a digital signal will take up less space. the sales force has been well trained in the best BS that can be had.

In most cases, the digital signal will not go as far as an analog signal and be understood as well. However, some of the real new digital radios do have better error recovery than the older ones and do better than their earlier digital radios at recovering the digital signal from a weak signal. The range is about comperable to an analog signal.

Narrow band on the other hand, due to the signal to noise ratio within the radios tends to not provide the same signal propagation as a normal band width signal we are all use to. There are many studies that have been done to both prove this and to also try to blow this theory out of the water. I would suggest that anyone with questions on the subject talk to an agency and find out first hand what they say. Your probably going to get an answer that will prove they lost coverage for the same power out and the same antenna system being used after they went narrow banded.

 

[WA1ATA]

Kito ...... your best bet is to ignore all of the extraneous back and forth regarding digital vs. analog signals and read the post by LtDoc 2 posts above this one.

Although you noticed a difference between two scanners, the most important thing by far is the signal level at your antenna. 800MHz signals are more or less limited to line of sight. The horizon or hills or other obstructions are probably reducing the level of the desired signal at your listening location. The best thing you can do is to get an external antenna as high up as possible.

The easiest way to see if this is likely to get you acceptable reception is to just take your handheld PRO 95 scanner up onto the roof and see how much the reception improves.