TRX1 (squelch) sensitivity observations

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I own a TRX1 for a few weeks now and its a great scanner. DMR/NXDN reception on outside antenna is great. Compared to my Hytera PD685 it seems to have same sensitivity . Very good narrow filter also (no bleed over). Analog reception on outside antenna is also very good; comparable to my BC346XT.
Almost no intermod (only some pager bleedover on VHF)

But when using the scanner mobile(outside) with rubber duck antenna i noticed it is receiving less than the Hytera. Also on analog signals my BC346XT is receiving signals the TRX1 wont. Particularly on UHF band.
When i turn the squelch all the way to the left the signal is there, but it just wont open the squelch.
(channel is not marked as skipped and i am not near transmitter towers or in high RF area).

Maybe the scanner has a different kind of squelch circuit compared to the Uniden or Hytera?
Anyone else noticed this too?
 

buddrousa

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The factory antenna on the TRX-1 is not a very good antenna you need to find a Radio Shack and get a RS 800 before they are all gone with Radio Shack closing.
 

buddrousa

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I have 4 Remtronix 2 BNC and 2 SMA and they perform just as good as my RS800 if you can find a RS store you can save about $4 plus shipping right now.
 
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Well, i am living in Europe and there's no 800 Mhz use here
Almost all DMR / NXDN in my country is in the 450-470 Mhz band and i'm allready using a tuned ducky for that band.
But still the BC346XT is outperforming the TRX 1 on UHF when used mobile.
When listening at home using an outside antenna i have no problems hearing the same weak signals on the TRX-1 as i receive on my BC346XT.
 
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buddrousa

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The Remtronix and RS800 work great on VHF 150, UHF 450, 700 and 800 bands also. My range with my standard antennas is almost doubled with the Remtronix and RS800 antennas.
 

Ubbe

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There have been some reports in the RR forum that the TRX-1 have the same problem as the Uniden 436, that the scanners electronics emits RF interferencies. The squelch circuit always detects the highest frequencies of the detected audio and it is possible that an interference will increase the high frequency noise even if the speech band of the audio seems to be unaffected.

One of the reports mentioned that screening the battery compartment helped, the same way that it solves the problem with the 436.

/Ubbe
 

SCPD

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odd

Well, i am living in Europe and there's no 800 Mhz use here
Almost all DMR / NXDN in my country is in the 450-470 Mhz band and i'm allready using a tuned ducky for that band.
But still the BC346XT is outperforming the TRX 1 on UHF when used mobile.
When listening at home using an outside antenna i have no problems hearing the same weak signals on the TRX-1 as i receive on my BC346XT.
Ok so at home it works with the outside antenna and when used mobile the Uniden is working better?Sounds like theres something not quite connecting in the mobile,check your antenna and or connections in the mobile from what you said its the mobile setup. Another thought could be the vehicle's computer is interferring with the TRX1 in some way,move the antenna and or coax as far away from the center console or passenger kickpanel where the vehicle computer could be,if its a chevy the computer is under the hood.
 
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Thnx Ubbe. I will try if shielding gives improvement in reception on the ducky.
Maybe testing by wrapping the scanner in aluminium foil ;)
The scanner also generates a few birdies (for example on 467.250 Mhz) only when using the ducky. On the external antenna the birdie is gone; the coax is shielding RF interferencies from the TRX-1.
In Europe Uniden just released the UBCD3600XLT (European version of the BCD436HP) and some owners allready mentioned less sensitivity on UHF compared to the previous model UBC3500XLT. So maybe it has something to do with the digital signals now decoding by the new generation scanners.

Mark

There have been some reports in the RR forum that the TRX-1 have the same problem as the Uniden 436, that the scanners electronics emits RF interferencies. The squelch circuit always detects the highest frequencies of the detected audio and it is possible that an interference will increase the high frequency noise even if the speech band of the audio seems to be unaffected.

One of the reports mentioned that screening the battery compartment helped, the same way that it solves the problem with the 436.

/Ubbe
 

kc2kth

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The Remtronix and RS800 work great on VHF 150, UHF 450, 700 and 800 bands also. My range with my standard antennas is almost doubled with the Remtronix and RS800 antennas.
That's a tip I hadn't seen before and something I was curious about - that the RS 800 everyone raves about does well on VHF-Hi and UHF as well. I was especially curious about VHF-Hi since I still have a lot in the 152-159 MHz range near me. I also have a 500 MHz system and a 700 MHz one that I monitor, Might order a couple of these and see how they do here.
 

DJ11DLN

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The RS800/Remtronix 800B won't outperform a resonant antenna on VHF-Hi...but it comes awfully close, and it seems to do quite as well on UHF as a resonant. This makes it a very good compromise for multi-band scanning. Even at the current inflated price, it's a worthwhile purchase.

That said, the OP seems interested in VHF-Hi/UHF, so perhaps an RH77C or other Ham 2M/440-type of antenna might be a good choice to try? They're cheap enough...he can always switch to the RS800 if the dual-band is too long or doesn't suit his needs.
 

AggieCon

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If scanning digital only, I keep my squelch low, sometimes all the way down. It seems to help.

Regarding antennas, I think the RS800 is overpriced. This one is more reasonable: http://amzn.to/2nb1He5. I have both, and I use this one a lot more. It's also tuned a bit lower, which is nice because there is a lot of loud cellular and other crap up high.
 

Machria

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The factory antenna on the TRX-1 is not a very good antenna you need to find a Radio Shack and get a RS 800 before they are all gone with Radio Shack closing.
buddrousa is right. A better antenna will make a difference. If you can't find an RS800, you can get the same antenna through Universal Radio made by Remtronix. I use the Remtronix antenna on my TRX-1.

Remtronix REM-800B, Diamond REM-800S Scanner Antenna
The Remtronix and RS800 work great on VHF 150, UHF 450, 700 and 800 bands also. My range with my standard antennas is almost doubled with the Remtronix and RS800 antennas.
If scanning digital only, I keep my squelch low, sometimes all the way down. It seems to help.

Regarding antennas, I think the RS800 is overpriced. This one is more reasonable: http://amzn.to/2nb1He5. I have both, and I use this one a lot more. It's also tuned a bit lower, which is nice because there is a lot of loud cellular and other crap up high.
Sorry to jump in here, but I'm clueless when it comes to antenna's. My new TRX1 is working just fine with everything I listen to, but better reception is always welcome of course. I'm going to install an external multi-band scanner antenna on my roof this summer. But in the meantime, does that amazon unit at $8 work better across all bands for the most part, or just a certain band? And how about the 15.5" version of that, is that better at a particular band or across all?

I don't care how much they cost, I'd like to get the best "portable" antenna I can for the TRX1 that works across all bands, from 25 to 1200. What would you guys suggest?
 

AggieCon

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I'm always a bit hesitant about "multi-band" stuff. Sure, it might be convenient, but I would still go for a specifically tuned antenna any day.

With a telescopic antenna (http://amzn.to/2ncA1pf), you can adjust the length to match something specific. Though I'm not sure if you'd want to throw your radio in your pocket with it fully extended.

The antenna I linked to in my previous post will do well with anything, provided there is sufficient signal strength. It's what I use 90% of the time on my handheld, even when listening to VHF.

Properly tuned antennas are most important for receiving broadcasts that are weak or cannot otherwise be received. Strong signals will be easy; others are more difficult. For instance, if you are trying to get simulcast trunked stuff in the 800s, an antenna tuned to 800MHz is important--that same antenna should also do strong VHF just fine.

Now, for transmitting, it's a completely different ballgame. Your antenna really needs to be appropriately tuned then. But for receiving, it's basically a function of dialing in to a marginal signal that you want to improve reception of.
 

Machria

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Thanks.... I understand your hesitation, and the fact if you tune it to one band, it will likely negatively affect the other bands. I get that part... I also understand broadcasting is another story as well of course.

I guess the question really is, and there is probably 10 different answers to it, which is the best "all around" portable scanner antenna's for most situations?

Or, is that $10 amazon rubber guy you first posted better all around than the Whistler in the box ducky?

I have had for 20 years, and use once in a while the old Radio Shack loaded telescoping antenna (picture included). But I never really noticed any difference while using that ant over the standard rubber ducky that comes in the box. But I also always forget the best way to extend it for different bands. For example do I extend the bottom half with the load ending up at the top, or do I extend the top half with the load staying at the midpoint....

Antenna's are very complicated, I know. I once listened to a TechNet on a Ham band for a few hours where a well known antenna designer (designed the NASA Lunar module antenna's among other well known stuff in the 60's and 70's) tried to explain some "stuff" and I had a headache very quickly!
 

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AggieCon

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I think the ExpertPower one (and the RS800 for that matter) is much better than the stock Whistler BNC protector. There are a ton of options out there. One could spend a lot (of money and time) on antennas. I try to get things done efficiently and conservatively. I am not sure anyone is going to agree on the "best portable antenna," but if you buy that one I linked to and don't like it, I'll be shocked. And I am confident a radio would break before it did; it's really durable.
 

Machria

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I think the ExpertPower one (and the RS800 for that matter) is much better than the stock Whistler BNC protector. There are a ton of options out there. One could spend a lot (of money and time) on antennas. I try to get things done efficiently and conservatively. I am not sure anyone is going to agree on the "best portable antenna," but if you buy that one I linked to and don't like it, I'll be shocked. And I am confident a radio would break before it did; it's really durable.
Aggie, thanks for the tip!

Received the $7 Expertpower from Amazon today, stuck it on and can immediately see a fairly big difference. I'm actually very suprised, I thought maybe I "might" see a percieved difference on a band or particular frequency or something.... instead I'm seeing a big improvement on just about everything. I'm picking up a HAM repeater that is about 40 miles from my house that I could not get with the regular antenna on the TRX or my BCD396. Interesting. The 800 band has lit up freq's I have had programmed but never pick up anything...both conv and digital. Not only am I picking them up now, they are chrystal clear...

So I'm going to go out on a limb here, and say WOW, big difference. I thought I was doing ok, apparently not. I guess falls under "You don't know what you don't know".
 
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