Funny thing, that Uniden sensitivity stuff!

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safetyobc

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I have complained about the sensitivity of my BCD396T from time to time. But I just accept it and go on most of the time. Occassionaly dropping a complaint about it here and there on various forums. I have compared the sensitivity to other units I have either owned or used extensively like a BC246T, Pro-97, Pro-96, Yaesu VR-120 and a few base/mobile models.

I recently sold all my radios except the BCD396T to purchase a BR330T (on the way) and a BCT15 (on pre-order). So I am left with just the BCD396T to play with.

While using the Pro-97 and others, I primarily used a Diamond RH77CA on it. It pulled in signals my BCD396T wouldn't, but I never used the RH77CA on the 396 more than a few seconds at a time. I'd hear the signal on the 97, move the antenna to the 396 and when it scanned by the system, I'd put it back on the 97. I never gave it a real chance.

The Pro-97 does well, but I have found that both the 97 and the 396 using RS800 antennas, the 396 was picking up and properly tracking a trunked system 40 miles away while the 97 wouldn't even find the CC. When it did catch the CC, the audio had loads of static at times.

I used a stock antenna from a Pro-2055 on my Yaesu VR-120 constantly and it would absolutely kick the crap out of the Pro-97 using the RH77CA. The VR-120 was so sensitive that it overloaded very easily though.

Normally I run the Radio Shack 800 MHz antenna on the 396 and complain it isn't sensitive enough. I do have a Centurion VHF-High antenna for the 396, but rarely use it because it isn't very good. It is okay, but not great. So while I am complaining about the 396, I never really gave it a fighting chance. So the last few days I have been using the Diamond RH77CA and the stock Pro-2055 antenna with the BCD396T. I have to say, I have been impressed. I am listening to signals that the VR-120 and Pro-97 were pulling in. It seems as though the longer I leave a particular anteann on the 396, the better it receives. I know that has nothing to do with it, but it is really doing well.

Now, I realize that you can't necessarily go out walking or take these antennas around easily since the 2055 antenna and the RH77CA are longer than one would normally like for everyday travel. But for sitting on the desk using one of ScannerStandMan's creations, it works great. I was actually a little worried about getting rid of my Pro-97 for a BR330T because of sensitivity issues. But now, I am excited to get the 330 here. I can return the 396 back to digital duties and the 330 can assume the analog responsibilities!

The antenna makes just as much, if not more, of a difference on sensitivity as the radio. DUH! I know. But what I did was buy a VHF-High tuned antenna, stuck it on the 396 and expected it to pull the signals in. When it didn't I accused the 396 of being deaf. Maybe it was the crappy antenna and not the 396. The Diamond and 2055 antennas I use for VHF-High, work really well for MY applications. The RS800 antenna works very well for me too. Pulling in analog 800 MHz towers at nearly 40 miles at times. Digital towers about the same distances at times.

So I guess I take back my sensitivity comments on the 396. I continue to be amazed by this scanner. I think it is possibly the greatest hand held scanner ever built. 1 year after purchasing this scanner, it is the only scanner I have kept around. All others find themselves coming and going within a few months. If I like the 330 and BCT15 as much, I may have a completed shack.........for a while anyway. Well, the Pro-2055 is bugging me not being Dynamic Memory, so it may find it's way out of the shack to make room for another BCT15 in the future? The 2055 will likely sell without it's antenna..this thing is great on VHF-High. Where can I get another?

Again, these are my observations here in South Arkansas. Of course others experiences are going to vary. I guess what I am getting at is that I should have experimented with various antennas with various radios before I called the radio junk.

The scanner / antenna combination is the key to a scanner nerd's happiness!
 

69stiles

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Apr 21, 2003
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225
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Waterloo Region
You know a while back I posted questions on why my GRE units, 97, 2055, could not grab the CC 10 miles out from the tower when my Uniden units, br330t, 2051, will with no problem on the same antenna. This issue I have is on the Bell Fleetnet/smartnet here in Ontario. This issue is why I bought 2 of each just to prove to myself that some systems work better with certain manufacturers. I could never get a solid answer on this but of course lots of people tried to help.
 

yaesumofo

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Jan 4, 2003
Messages
314
Location
los Angeles
Using the proper antenna is key with the 396. I have a collection of over 25 antennas for my Handhelds.
I also believe the 396 is one of the best scanners ever made. It has the best feature set of any hand held ever made. My 396 is not as sensitive as my BC-780 base radio. I do believe it has slightly better selectivity.

On most scanners which are more sensitive there is a price to pay in he form of inter modulation and overload. Scanner design is a tight rope. too much sensitivity and the front end of the radio is always overloaded. Too little and you don't hear anything.
The 396 has a very good balance of sensitivity and selectivity.

Antenna choice really makes the difference with the 396 an antenna tuned to the area that you want to monitor really gives it the edge without overloading the front end.

I Have never heard any intermod on my 396 and haven't noticed anybody ever complaining about it.

I just wanted to post something in support of this great radio. I also look forward to the next generation of uniden scanner. You know the one with dual receivers, and a flash memory slot. There are other features I look forward to but those are 2 that I really want. I will most likely skip the 996. The 396 meets my needs very well. I don't need GPS in a scanner that will never leave my shack. Now GPS in an ht? That I would go for, It it very possible too. They now have single chip GPS solutions which are tiny, so they should have no problem integrating GPS into the next gen uniden HT.

BTW I have had great success with telescoping antennas. Maldol makes one that is very good (Maldol AH-W100RX) so does Watson. The unit radio shack sells isn't bad either. I saw somewhere a chart which when printed and taped to the side of the antenna shows you the lengths for tuning it to a specific frequency.
The thing about telescoping antennas is you can really tune the antenna to what you want to hear. One telescoping antenna can replace several "tuned" antennas.

I also have a small version of the rh77ca which is my general use antenna.
If anybody is even thinking about getting a 396. STOP. Thinking and just do it. You will be glad you did.
Yaesumofo





safetec said:
I have complained about the sensitivity of my BCD396T from time to time. But I just accept it and go on most of the time. Occassionaly dropping a complaint about it here and there on various forums. I have compared the sensitivity to other units I have either owned or used extensively like a BC246T, Pro-97, Pro-96, Yaesu VR-120 and a few base/mobile models.

I recently sold all my radios except the BCD396T to purchase a BR330T (on the way) and a BCT15 (on pre-order). So I am left with just the BCD396T to play with.

While using the Pro-97 and others, I primarily used a Diamond RH77CA on it. It pulled in signals my BCD396T wouldn't, but I never used the RH77CA on the 396 more than a few seconds at a time. I'd hear the signal on the 97, move the antenna to the 396 and when it scanned by the system, I'd put it back on the 97. I never gave it a real chance.

The Pro-97 does well, but I have found that both the 97 and the 396 using RS800 antennas, the 396 was picking up and properly tracking a trunked system 40 miles away while the 97 wouldn't even find the CC. When it did catch the CC, the audio had loads of static at times.

I used a stock antenna from a Pro-2055 on my Yaesu VR-120 constantly and it would absolutely kick the crap out of the Pro-97 using the RH77CA. The VR-120 was so sensitive that it overloaded very easily though.

Normally I run the Radio Shack 800 MHz antenna on the 396 and complain it isn't sensitive enough. I do have a Centurion VHF-High antenna for the 396, but rarely use it because it isn't very good. It is okay, but not great. So while I am complaining about the 396, I never really gave it a fighting chance. So the last few days I have been using the Diamond RH77CA and the stock Pro-2055 antenna with the BCD396T. I have to say, I have been impressed. I am listening to signals that the VR-120 and Pro-97 were pulling in. It seems as though the longer I leave a particular anteann on the 396, the better it receives. I know that has nothing to do with it, but it is really doing well.

Now, I realize that you can't necessarily go out walking or take these antennas around easily since the 2055 antenna and the RH77CA are longer than one would normally like for everyday travel. But for sitting on the desk using one of ScannerStandMan's creations, it works great. I was actually a little worried about getting rid of my Pro-97 for a BR330T because of sensitivity issues. But now, I am excited to get the 330 here. I can return the 396 back to digital duties and the 330 can assume the analog responsibilities!

The antenna makes just as much, if not more, of a difference on sensitivity as the radio. DUH! I know. But what I did was buy a VHF-High tuned antenna, stuck it on the 396 and expected it to pull the signals in. When it didn't I accused the 396 of being deaf. Maybe it was the crappy antenna and not the 396. The Diamond and 2055 antennas I use for VHF-High, work really well for MY applications. The RS800 antenna works very well for me too. Pulling in analog 800 MHz towers at nearly 40 miles at times. Digital towers about the same distances at times.

So I guess I take back my sensitivity comments on the 396. I continue to be amazed by this scanner. I think it is possibly the greatest hand held scanner ever built. 1 year after purchasing this scanner, it is the only scanner I have kept around. All others find themselves coming and going within a few months. If I like the 330 and BCT15 as much, I may have a completed shack.........for a while anyway. Well, the Pro-2055 is bugging me not being Dynamic Memory, so it may find it's way out of the shack to make room for another BCT15 in the future? The 2055 will likely sell without it's antenna..this thing is great on VHF-High. Where can I get another?

Again, these are my observations here in South Arkansas. Of course others experiences are going to vary. I guess what I am getting at is that I should have experimented with various antennas with various radios before I called the radio junk.

The scanner / antenna combination is the key to a scanner nerd's happiness!
 

Dewey

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Joined
Dec 19, 2002
Messages
1,025
I guess it's time for me to chime in with a very interesting observation also. I have, and still do complain about the 396's sensitivity ( http://www.radioreference.com/forums/showthread.php?t=38184 ). However, I am beginning to believe that it might be the make up of the radio, and not the radio itself. My 396 is my next to most deaf scanner when using various portable antennas. The only handheld that I have that is more deaf than my 396 is my Pro-92B... another handheld that had a hot receiver in the "A" models, but something was done to fix the buggy firmware that made the "B" and later models deaf.

Well back to the 396... I've noticed that when I run the 396 on my RS dual coil mag mount mobile antenna, it holds it's own. It is just as sensitive as the other portables when run on the same antenna (not at the same time). However, once the duck, any duck, this includes RS's collapsable antenna is installed, the 396 goes back to hard of hearing. Now, while I am in no way a radio tech, nor do I play one on TV, I can't help but wonder if it's something about the 396 that affects it's portable performance. I have two ideas that may be causing this; A) the 396 is so small that it has no form of ground plane whatsoever while the other scanners sizes give them at least a small footprint for a partial ground plain; or B) maybe the curcuitry of the 396 is causing a deafening affect that can be overcome once a mobile antenna is installed which removes the antenna from the radio itself, AND gives the radio a comparable ground plain.

Either way, I still complain about my 396's sensitivity... that is... until it's intalled in the vehicle. BUT, this is still supposed to be a PORTABLE scanner.

Just my .02,
Dewey
 

yaesumofo

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Joined
Jan 4, 2003
Messages
314
Location
los Angeles
What we really need is an independant party to test the 396 on the bench to determine the sensitivity on various bands.
Maybe we can talk the arrl into a review now that the radio has been out over a year and the firmware is most likley not going to change.
yaesumofo


Dewey said:
I guess it's time for me to chime in with a very interesting observation also. I have, and still do complain about the 396's sensitivity ( http://www.radioreference.com/forums/showthread.php?t=38184 ). However, I am beginning to believe that it might be the make up of the radio, and not the radio itself. My 396 is my next to most deaf scanner when using various portable antennas. The only handheld that I have that is more deaf than my 396 is my Pro-92B... another handheld that had a hot receiver in the "A" models, but something was done to fix the buggy firmware that made the "B" and later models deaf.

Well back to the 396... I've noticed that when I run the 396 on my RS dual coil mag mount mobile antenna, it holds it's own. It is just as sensitive as the other portables when run on the same antenna (not at the same time). However, once the duck, any duck, this includes RS's collapsable antenna is installed, the 396 goes back to hard of hearing. Now, while I am in no way a radio tech, nor do I play one on TV, I can't help but wonder if it's something about the 396 that affects it's portable performance. I have two ideas that may be causing this; A) the 396 is so small that it has no form of ground plane whatsoever while the other scanners sizes give them at least a small footprint for a partial ground plain; or B) maybe the curcuitry of the 396 is causing a deafening affect that can be overcome once a mobile antenna is installed which removes the antenna from the radio itself, AND gives the radio a comparable ground plain.

Either way, I still complain about my 396's sensitivity... that is... until it's intalled in the vehicle. BUT, this is still supposed to be a PORTABLE scanner.

Just my .02,
Dewey
 

acetech

Member
Joined
Feb 26, 2003
Messages
56
The 330 is a little more sensitive then the 396. I have the srh77ca, but what i use a lot is the SRH519. I love this antenna and it works great.
 

wesct

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Joined
Jul 20, 2005
Messages
764
Location
Connecticut
yaesumofo said:
What we really need is an independant party to test the 396 on the bench to determine the sensitivity on various bands.
Maybe we can talk the arrl into a review now that the radio has been out over a year and the firmware is most likley not going to change.
yaesumofo

maybe i can arrange that

i have a friend who is in charge of a radio shop and has alot of uniden radios. we will see....


wesct
 
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pro92b

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Messages
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wesct said:
maybe i can arrange that

i have a friend who is in charge of a radio shop and has alot of uniden radios. we will see....


wesct

Already been done. Here is a repost with the 996 added (the last three columns are for the 996).

Code:
20 dB Quieting Test, All Channels NFM Mode
Frequency BC246T BCD396 BC796D BC780XLT BCD996 Sq Opens SQ Closes
030.00000 0.28uV 0.33uV 0.34uV 0.44uV . 0.32uV  0.23uV   0.16uV
040.00000 0.30uV 0.30uV 0.25uV 0.45uV . 0.31uV  0.23uV   0.16uV
050.00000 0.29uV 0.31uV 0.25uV 0.43uV . 0.29uV  0.21uV   0.14uV
125.00000 0.38uV 0.30uV 0.34uV 0.50uV . 0.27uV  0.21uV   0.14uV
135.00000 0.36uV 0.34uV 0.31uV 0.43uV . 0.27uV  0.21uV   0.13uV
144.00000 0.32uV 0.27uV 0.35uV 0.43uV . 0.25uV  0.20uV   0.13uV
155.00000 0.33uV 0.30uV 0.29uV 0.42uV . 0.25uV  0.19uV   0.13uV
170.00000 0.33uV 0.30uV 0.34uV 0.46uV . 0.25uV  0.19uV   0.13uV
250.00000 ------ 0.32uV 0.27uV 0.40uV . 0.28uV  0.20uV   0.13uV
300.00000 ------ 0.35uV 0.32uV 0.55uV . 0.26uV  0.19uV   0.13uV
350.00000 ------ 0.33uV 0.34uV 0.24uV . 0.33uV  0.24uV   0.18uV
410.00000 0.29uV 0.35uV 0.23uV 0.25uV . 0.32uV  0.24uV   0.18uV
460.00000 0.32uV 0.39uV 0.23uV 0.26uV . 0.32uV  0.25uV   0.18uV
500.00000 0.30uV 0.39uV 0.24uV 0.32uV . 0.31uV  0.23uV   0.17uV
765.00000 ------ 0.47uV . . . . . . . . 0.39uV  0.25uV   0.15uV 
855.00000 0.38uV 0.44uV 0.41uV 1.20uV . 0.29uV  0.24uV   0.17uV
935.00000 0.40uV 0.57uV 0.43uV 1.40uV . 0.32uV  0.24uV   0.18uV
 
Fluke 6060B Signal Generator
Wavetek A151 20dB Attenuator  DC-2000 MHz
Pomona 2249-C-36 RG-58 cable (Belden 8262), 3 feet long, -0.6dB @ 900 MHz
Audio isolated detector circuit
Fluke 8050A meter, DC scale, dB function

The small size of the ground plane on the 396 does adversely affect reception. Sometimes holding the radio brings up the signal a bit because then you become part of the ground through capacitive coupling.

All radios vary a bit in production and some samples are more sensitive than others. There is no real reason why the 330 and 396 should be much different. The PRO-92 sensitivity varied greatly among samples and some users incorrectly attributed that to firmware. In fact firmware does not affect sensitivity at all.

The numbers in the chart reflect very ideal conditions - one signal coming into the radio. In the real world with many signals present, varying degrees of overload are possible which can reduce the apparent sensitivity.

Bottom line is that for raw sensitivity, the 396 compares well to the others on a signal generator test. How well that translates to real world usage depends on the RF environment and what type of antenna is used. As noted above, physically larger radios will have an advantage if a portable antenna is used.
 

rhutch

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Ontario
I've used the srh77ca and the SMA 3 side by side and I find the SMA 3 to perform better in both the 142-145 Mhz raange and the 800 Mhz range.
 

wolter

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Joined
Dec 19, 2002
Messages
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Dewey said:
I have two ideas that may be causing this; A) the 396 is so small that it has no form of ground plane whatsoever while the other scanners sizes give them at least a small footprint for a partial ground plain; or B) maybe the curcuitry of the 396 is causing a deafening affect that can be overcome once a mobile antenna is installed which removes the antenna from the radio itself, AND gives the radio a comparable ground plain.
The Icom R2 is nearly half the size of a 396T and it blows away the 396T in a reception comparision. So I'd lean more towards 'B'.
 
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