BCD436HP/BCD536HP: Distortion dmr .. more updates?

[jfmartin]

Will there be more updates for the bcd436hp? I feel that dmr has a little distortion that in dsdplus does not happen ..

 

[buddrousa]

In the words of the late UPMan what system as all users may not be having this problem.

 

[jfmartin]

in DMR certain stations that have a loud voice output a little saturated at 436hp it is difficult to understand what they say instead the same situation in a dsdplus clearly understands the voice or almost ... on the company's Motorola radio it is also heard well .

 

[jonwienke]

If the distortion is heard on a Motorola system radio, then a firmware update isn't going to fix it.

What does it sound like using headphones?

 

[Whiskey3JMC]

in DMR certain stations that have a loud voice output a little saturated at 436hp it is difficult to understand what they say instead the same situation in a dsdplus clearly understands the voice or almost ... on the company's Motorola radio it is also heard well .

I usually apply a negative volume offset to each over-modulated channel/talkgroup and this seems to alleviate what I believe you're describing here

 

[jfmartin]

If the distortion is heard on a Motorola system radio, then a firmware update isn't going to fix it.

What does it sound like using headphones?

no, on Motorola radio it sounds good and on sdr too. It sounds better ..

 

[jfmartin]

If the distortion is heard on a Motorola system radio, then a firmware update isn't going to fix it.

What does it sound like using headphones?

by earphone it sounds the same, usually it sounds good but at certain times by loudspeaker and by earphone if even at low volume it distorts some of the people who speak (not all) it is as if they shout ..

 

[Ubbe]

I usually apply a negative volume offset to each over-modulated channel/talkgroup and this seems to alleviate what I believe you're describing here

I will try that but as I understand it only changes the volume step that you set from the volume control. When people set it to +1 they cannot mute the audio by setting the volume to 0.

As jfmartin describes DMR sometimes sounds overmodulated but on DSDplus or a Whistler scanner or a cheap DMR radio the same transmission sounds fine.

Uniden did an audio change a couple of firmwares back to make the audio sound better so they might have gone a bit too high in audio level before the stage in the circuit where the volume control kicks in and controls the audio level.

/Ubbe

 

[JJMNIZ]

Try setting the scanner for FM instead of NFM.

 

[jonwienke]

Try setting the scanner for FM instead of NFM.

That has no effect on the volume level of decoded digital bits, only analog signals.

 

[JJMNIZ]

I was referring to the following post in The Uniden Tavern:

dmr WFM ? NFM ?

 

[jfmartin]

NFM

 

[Ubbe]

The volume offset didn't change anything for the overloaded audio level for me. Uniden have fixed the firmware so it always mute on volume 0 regardless of the volume offset setting. If I set it to -3 it behaves a bit strange as it goes quiet already at volume 6, so 1-6 have no audio.

/Ubbe

 

[jfmartin]

a month ago I bought this used 435hp equipment ,,, activate dmr ... by chance I found the post that talked about putting copper or aluminum foil (already closed). my team does not have the C1 and the truth is that I found no noise but out of curiosity I just put on the cover a sheet that had a hard drive of a pc this laminated plasticized aluminum and I put a frequency that I hear a lot in 470 .... In dmr and Channnnnn I skip active reception much better no matter how I place it in position the reception is activated, before I had to look for certain areas of the house and positions to receive the signal .... it is incurable that such a large and so easy to fix it will be ignored not justified ... If it receives better or better activates the dmr and surely analog signals when isolating the internal frequency region.

 

[jonwienke]

Most of the boards missing C1 are part of the display/clock recall, and Uniden replaces them for free as part of the repair campaign for those issues.

If your scanner is missing C1, reception is primarily affected if you're using the stock antenna or something similarly short. THe range of the noise is very limited and if you use an antenna like the Diamond RH77CA or any external antenna connected via coax, the RFI effect is negligible.

 

[ChrisABQ]

Make sure your on the latest firmware. You may even try rolling it back to an earlier version to test audio quality as there have been digital enhancements in the latest version.

 

[jfmartin]

problem with the translator sorry .. message was repeated

 

[jfmartin]

Most of the boards missing C1 are part of the display/clock recall, and Uniden replaces them for free as part of the repair campaign for those issues.

If your scanner is missing C1, reception is primarily affected if you're using the stock antenna or something similarly short. THe range of the noise is very limited and if you use an antenna like the Diamond RH77CA or any external antenna connected via coax, the RFI effect is negligible.

the problem that is used in 2013 I think and they already opened it and they changed the speaker (I put a more decent one again than the other person who had it put a very bad one and 8 ohms I put a 1w 16 ohms since I did not see 24) it has the internal resistance R but not the capacitor C1 I would put it but it scares me a bit since it is a bit delicate to the small one and I am used to soldsr larger components and the heat gun that I have a little grade the output .... the aluminum (RF or static protector of an HDD) has improved the reaction remarkably to the point that even if it touched the antenna it follows the signal, without aluminum even looking for the point of more signal in If I touched it with my hand, I lost a signal ... so find more information on how to put and get the C1 and decide to put it on, I will settle for the moment with the aluminum and buy copper foil to see if it has any difference with the aluminum (I guess that copper absorbs RF and aluminum reflects it or so I think

 

[jfmartin]

I forgot to say, I am in Chile (I am Spanish but I live in Chile)

 

[jonwienke]

Does your board have the pads for C1? They are just above the upper-right battery terminal looking at the main board from the back side.

The hardest part about soldering the capacitor in place (.01 microfarad) is holding it in position. An assistant with steady hands holding it in place while you solder the first joint is helpful. Even using paste solder, if you don't melt the solder on both ends of the capacitor at the same time, the surface tension of the melted solder can move it out of position.

I use the paste solder, and hold the capacitor in place with a dental pick in one hand, and the soldering iron in the other hand. Don't drink coffee first. The capacitors are cheap, get a 10 or 25-pack and practice soldering them on scrap circuit boards or metal pieces before trying on the scanner. It is difficult, but you can learn to do it, unless you have parkinson's disease or something like that.