2 bcd436hp's 1 receives better than the other

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Badboy536

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Hi thanks for reading this.i have 2 ,436hp's. One of them the one that does not receive as well as the other is my Original one I got brand new in 2014.Recently I picked up another 436 on Craigslist in new condition. When put side by side both using the stock antenna the craigslist 436 out receives my Original 436 I got new.both have the latest Firmware and database on them.i even Reinstalled the latest firmware on the 436 that does not receive as well just to see if that would help.it didnt.the craigslist 436 seems to pick up about 2 bars better on the signal meter and will stop on stuff that my Original 436 will not.the craigslist 436 almost seems like it is more Sensitive to picking up signals.i would have never known this if I didnt buy this second 436 from Craigslist. Any thoughts would be Appreciated.
 

JamesO

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What Frequency range are you monitoring that the first unit does not receive well on?

Do you know that the attenuation is not enabled?

Do you think there may be a problem with the antenna jack?
 

TeK-NO

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bcd436hp's

I think the BcD 396xt has way better reception that the 436hp. I think it really sucks for that they could have done a better good. Luck for you you have a next one with better strength. I have heard other people with the same problem. Even the audio is weak.......
 

Badboy536

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What Frequency range are you monitoring that the first unit does not receive well on?

Do you know that the attenuation is not enabled?

Do you think there may be a problem with the antenna jack?


The attenuator is off and the antenna jack is fine..
 
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Badboy536

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The frequency range is in the 150 megahertz VHF and the 482 and 500 megahertz UHF.its seems to be OK or the same in the 800 and 900
 

Badboy536

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I think the BcD 396xt has way better reception that the 436hp. I think it really sucks for that they could have done a better good. Luck for you you have a next one with better strength. I have heard other people with the same problem. Even the audio is weak.......

I agree the 396xt has very good receive.but this 436 I just got is pretty close to the 396xt..my original 436hp there's a big difference. The 396xt blows that one away.
 

sflmonitor

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Hi thanks for reading this.i have 2 ,436hp's. One of them the one that does not receive as well as the other is my Original one I got brand new in 2014.Recently I picked up another 436 on Craigslist in new condition. When put side by side both using the stock antenna the craigslist 436 out receives my Original 436 I got new.both have the latest Firmware and database on them.i even Reinstalled the latest firmware on the 436 that does not receive as well just to see if that would help.it didnt.the craigslist 436 seems to pick up about 2 bars better on the signal meter and will stop on stuff that my Original 436 will not.the craigslist 436 almost seems like it is more Sensitive to picking up signals.i would have never known this if I didnt buy this second 436 from Craigslist. Any thoughts would be Appreciated.

I had the exact same problem. One 436 worked perfectly and the other was deaf (well, almost). I decided to ship it back to Uniden as the deaf one was still under warranty. As it turns out, they replaced two components (Q2 &Q3 I believe). Now both are on par.
 

marksmith

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The 436 is less sensitive in the vhf range than the 396. Otherwise, the 436 I have is very much more sensitive and better at interference rejection than both of my 396 radios on all other ranges, especially 700-900 mz.



Mark
WS1095/536/436/996P2/HP1e/HP2e/996XT/325P2/396XT/PRO668/PSR800/PRO652
 

kruser

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I agree the 396xt has very good receive.but this 436 I just got is pretty close to the 396xt..my original 436hp there's a big difference. The 396xt blows that one away.

I wonder if it has anything to do with the battery door interference issue that has been a very active thread.

Try them both with an external antenna if possible.
I tried shielding my battery door in my 436 but if made zero difference when using the stock antenna. Many reported the same results so it seems that some 436 models do not emit interference from the battery compartment while some do.
That problem is non existent when using an external antenna so the theory is that the factory antenna is picking up internally generated noise from the radio itself.
Many claim shielding the battery door made a huge improvement mostly in the 450 MHz area.
I actually have two 436 models and do not get any RFI from the radios when using a duck antenna.

How far apart are the serial numbers from your original 436 compared to the eBay model?
There could have been an RF board change in between your models.

Using an external antenna should prove if the poor reception model is picking up internally generated noise.

The only other easy thing you may try if you have not already is swapping the SD cards between the models and see if the poor performance follows the card to the other radio.
That would point to a noisy card.

Any external antenna should work if you can place the antenna 10 or more feet from the radio as those with internal noise appear to report the noise is very low level so moving the antenna away from the radio is enough to improve reception back to normal.

If the poor reception model has any of the issues Uniden is fixing for free, taking advantage of that offer may just fix you up.

You could also make an antenna if you have a 6 foot or longer hunk of coax laying around with a BNC connector on one end. Just strip off about 6 inches of the shield on one end and find a weak UHF signal and see if the reception equals out between the two radios. If it does equal out the reception, then you may be a victim of the internal noise many are finding.
My two 436 models are old and new. One was purchased when they first released them and the other is fairly new with a recent serial number range but neither show any signs of internal noise. I even sniffed them both with an analyzer but neither were emitting anything bad so doing the battery door shield mod did nothing of course. I even played with different SD cards including the factory cards but could not get either to produce the noise that the large thread is talking about.
 

kruser

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I had the exact same problem. One 436 worked perfectly and the other was deaf (well, almost). I decided to ship it back to Uniden as the deaf one was still under warranty. As it turns out, they replaced two components (Q2 &Q3 I believe). Now both are on par.

That's interesting. If the beginning of the transistor numbering scheme starts with the RF input stage that could indicate blown RF amp transistors.
Back when you could still get service manuals, many models did start the component number starting at the antenna input and that number increased as you moved further away from the input on the RF board.
I've never studied the numbering scheme Uniden uses on any of their more recent products but it was fairly common that many did start the lowest number from the antenna end of the circuit.
I think logic boards started with the power supply end of the board having the lower part number on the board.
 

Ronaldski

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Swap antennas, occasionally the wires in the rubber duc can break
same agency types selected?
same ranges?
Try my reception FAQ's -
reception FAQ's

Look at imo 3, 6, 7, 8 and yes 11! Have had several people who asked me about their poorer reception and it did indeed fix it! Even when there are no smokers in the house,
 

SCPD

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436 better

Whats the firmware on both the less sensitive one and the better one?
I found different firmware performed differently.
Curious........

Mine was an older 436hp and it worked great on VHF high,poorly on 440.
 
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Badboy536

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Whats the firmware on both the less sensitive one and the better one?
I found different firmware performed differently.
Curious........

Mine was an older 436hp and it worked great on VHF high,poorly on 440.

Both of my 436's are on the latest Firmware both using the same type of antenna.i am wondering if
My 436 with less signal showing is more of a signal meter Calibration issue then real signal problem.
 

Badboy536

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And both of my 436's are from 2014 According to the serial number on the back.just one of themmi got new from ham radio outlet thats the one with less signal on the meter then the 436 I just got off of craigslist last week.i could not pass up the deal $300 and it was in brand new condition. I guess I got lucky because it seems to have better receive.
 

KR3LC

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Both of my 436's are on the latest Firmware both using the same type of antenna.i am wondering if
My 436 with less signal showing is more of a signal meter Calibration issue then real signal problem.

Don't trust the signal meter. Trust your ears. Especially on analog signals. And swap antennas and do a comparison back and forth. Don't trust that both antennas are performing the same anymore than you trust the radios to be performing the same. Best to use the same antenna on both radios. One at a time.
 

Ronaldski

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Q in electronics are transistors.

Additionals L is coils, Letter R is resistors, D's are diodes, IC are integrated circuits, C are capacitors
 
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