Whistler TRX-2 vs. Uniden SDS-100: Which Receives Better in P25 Multi-Cast Environment?

What's Your Favorite Brand Of Police Scanner?

  • Whistler/Gre/Radio Shack

    Votes: 18 22.0%
  • Uniden Bearcat

    Votes: 61 74.4%
  • Some Other Brand

    Votes: 3 3.7%

  • Total voters
    82
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DoctorZ

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The Whistler was either set at 1 or 2, the Uniden was set at 2. I also have analog channels in the scan so I have my squelch set at the lowest I can get by with without it opening on the analog/conventional freqs during scan. Uniden you can have the squelch off and it still only stops at conventional channels during traffic, (it slows down the scan speed though); but Whistler doesn't have that feature. You must have some squelch on Whistler to scan the Conventional stuff.
 

jaspence

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Was any check done to see if the RF from one radio was affecting the other? I have done that with two radios on the same frequency and seen a change in one radio's performance.
 

DoctorZ

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Those radios are RECEIVERS not transmitters. There should not be any RF coming from them. However, for the sake of argument I've had the Uniden for a week's time. It took me that long to set it up and program it the way I wanted. I've never owned a Uniden Scanner before so there was a learning curve. The Uniden was noticeably better than ANY previous scanner I've owned at receive right out of the box. This goes back to analog days. This Uniden is the first scanner I've ever owned that allows me to pick up our ENTIRE Twin Cities Metro Area from my current location. Some of this could be attributed to Simulcast, but since the Uniden even shows which sites it's receiving from, I know it's not all just Simulcast or rebroadcasts.

Finally, the beam antenna is about 80 feet away from the rubber ducky. RF would have to come from some other source and all my Ham Radios were OFF.
 
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DoctorZ

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That's just not true.

Almost every radio, even receivers, have RF emanating from them.

See here:
Local oscillator - Wikipedia

And here:
Beat frequency oscillator - Wikipedia

Heterodyne - Wikipedia

Two - or more - of these oscillators can interfere with the others.

Remember those small boxes you could put next to a transistor radio to hear police calls? Similar principle.

Nope, that must have been before my time. These are way beyond transistors, the RF produced by these radios is too small to make any difference. Besides I had the same results before I put the two radios next to each other for the video.
 

Ubbe

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You probably have some funky RF situation at your place. Whistlers TRX scanner close squelch first at a 8 setting but usuable levels are 9 or 10.
A straight metal telescopic antenna at 800MHz are not as good as the tuned dedicated 800MHz dual band antenna that comes with the Uniden scanner. People who monitors simulcast systems says that the TRX scanner are terrible at simulcast, worse than Whistlers older scanners. The SDS100 are a specific simulcast receiver that excels with those systems and in locations where there are very little other transmitters that could interfere but takes a hit in rich RF enviroments, especially in VHF and UHF where usually powerful broadcast transmitters for FM radio and television are found. In the right enviroment Unidens SDS series of scanners are excellent, and why shouldn't they when they are the latest technology available and Whistlers scanners in comparison are based on a very old design.

/Ubbe
 

DoctorZ

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I live in the forest miles from any RF source. I'm a Ham Radio operator so any RF in the area is caused by me. My location is so remote that we can't even get reliable cell phone service out here!
 

buddrousa

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What about a wireless router they produce RF.
What about LED LIGHTING they produce RF.
What about SMART TV's they produce RF.
What about the new WIFI dishwashers they produce RF.
All the rest of the new WIFI connected devices they produce RF.
My point is may new and old things produce RFI and the Whistler/GRE scanners suffer from frontend overload and your problem could be coming from anywhere. Trial and Error is the only way you could find your source.
 

kruser

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Nope, that must have been before my time. These are way beyond transistors, the RF produced by these radios is too small to make any difference. Besides I had the same results before I put the two radios next to each other for the video.

It does not matter if transistors or ICs are used, any radio device with a local oscillator will create local noise or RF. Granted, better radios will be shielded better than others but the source still exists. Some can be detected several feet away while better shielded LOs may be undetectable just a half inch away. It all depends on the design and often on how much was spent on the final design.

Look at Uniden's own BCD436HP portable. People were suffering from poor UHF reception but not if they used an external antenna. It was later found that something in the logic section was radiating noise across much of the UHF band and going right back into the radio's antenna which reduced its sensitivity across the UHF ranges and wiped out weak signal reception. This is no different than LO noise or stray RF from a nearby radio or even the test radio itself.
It's usually all very low level but still exists (even with today's technology) if you know how to look for it.

What buddrousa points are all very true (and proven) sources of RF noise. Switching power supplies are also some of the worst culprits and not just in the HF range either.
 
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DoctorZ

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Let's look at the bottom line. In my house, for whatever reason, the Uniden (and I'm no fan of Uniden) outperformed the Whistler not only on the digital bands, but it is also doing better on the VHF Bands. I have yet to test the UHF Band.

If it makes you Whistler fans feel any better I'm still keeping the Whistler in the Storm Chase Vehicle. The SDS100 did NOT do very well in the wife's van when moving. It had trouble with reception. I have a DPD Productions 800 MHz Double 5/8 Wave Mobile Scanner antenna on order which should help the problem. However it seems that the Uniden locks on to these very weak signals and that's not a good thing if you're moving down the road at 70 MPH with trees and buildings along the roadside.
 

iMONITOR

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I used to laugh when people would warn others that police could detect if you had a scanner radio in your vehicle by picking up RF emmissions from the scanner. I'm thinking no! Just an urban legend, total myth. While it is true scanners can emit some level of RF noise, police cars were never equipped to detect this, nor was anyone ever busted using this method. :rolleyes:
 

SteveSimpkin

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I used to laugh when people would warn others that police could detect if you had a scanner radio in your vehicle by picking up RF emmissions from the scanner. I'm thinking no! Just an urban legend, total myth. While it is true scanners can emit some level of RF noise, police cars were never equipped to detect this, nor was anyone ever busted using this method. :rolleyes:

As a side note, England has used TV Detector vans for decades to determine if a household is using a TV set without paying the annual TV viewing license fee. These vans are able to detect the RF emissions of a TV set while it is operating, as well as using other possible detection methods.
TV detector van - Wikipedia
 

DoctorZ

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As a side note, England has used TV Detector vans for decades to determine if a household is using a TV set without paying the annual TV viewing license fee. These vans are able to detect the RF emissions of a TV set while it is operating, as well as using other possible detection methods.
TV detector van - Wikipedia

I'm sure the TV's have something built in to emanate a special RF signal otherwise that van would be picking up a lot of other RF that wasn't TV's.
 
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