SDS100 P25 P2 audio imporvement?

DeDawg

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#1
As far as the search tool works, no one seems to have commented on whether the new radio has any improvement on the hideous digital audio decode quality of the 436 series.

I found the decoded digital un-listenable on a 536. Female dispatcher voice could peal paint, male voice often sounded like talking in a coat closet.

My little 325 is at least useful for some listening, but would welcome something smoother.
 

pinballwiz86

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#2
Have you tried going into the Menu and setting the Site's "Digital Threshold Mode" to "Manual" Then set the "Digital Threshold Level" to 8.
 
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#4
I think he is referring to the agc defect in the 436, and to answer your question because i asked upman about this very obvious defect, is there is no change in agc on the new sds100 from the x36 line.
 
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#5
Actually, there is, because AGC isn't even an available setting for the SDS100.

Regardless, I've posted side-by-side comparisons of audio from both scanners using the same antenna and site so you can hear the same transmission as received and decoded by each.
 
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#6
Have you tried going into the Menu and setting the Site's "Digital Threshold Mode" to "Manual" Then set the "Digital Threshold Level" to 8.
Went to my local system then selected the site and I don't see any option about digital threshold mode and threshold level.

Sent from my SM-G965U using Tapatalk
 
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#11
Setting it to manual and 8 gives me lower error rates than setting it to Auto. I'll look at it some more. Is this official or just your opinion?
Note: the following only appoes to x36 radios:
A few firmware versions ago, the actual voltage values associated with threshold numbers were adjusted, and the Auto algorithm was tweaked. Threshold 8 with current firmware is not the same as threshold 8 with firmware 1.11.xx. That is official, not opinion.

If you go into digital adjustment mode (scroll, FUNC, scroll on 436, scroll, volume on 536), watch the threshold value when in auto mode. If it holds on a value immediately and doesn't fluctuate more than ±1 from that value, there is no benefit to manually setting that value manually. If it fluctuates more than ±1 (which is usually a simulcast or weak signal issue), then watch the decode error number and note what threshold value corresponds with the lowest decode error, and set that value manually. The optimal threshold value varies from site to site, and sometimes from scanner to scanner. So a blanket recommendation of any manual threshold value is generally going to be wrong.

As noted before, the SDS100 does not use or need threshold settings for its I/Q demodulator, and therefore all threshold mode and value settings have been removed from the SDS100 menu, and in Sentinel favorite list editor when the active profile has the Target Model set to SDS100.
 

DeDawg

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#14
Have you tried going into the Menu and setting the Site's "Digital Threshold Mode" to "Manual" Then set the "Digital Threshold Level" to 8.
Yes, when I had a 536 I certainly did experiment all over with the digital settings while waiting for firmware to make it finally work and later while trying to decide to keep it or not. Got very low BER (site is only about 4 miles away) but voice quality was not much changed. Attenuator did not help looking to see if it was being overdriven.

The little 325 does not care much.

Guess i was hoping to hear that voice decode had smoothed out and was not as susceptible to what sounds like overmodulation.
 
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#15
With digital, overmodulation happens when the audio is encoded to bits. If the transmitting radio is adjusted such that the audio is being clipped when digitized, there is nothing you can do to fix that on the receiving end. There are some units on some digital systems I monitor that are badly clipped, and others that are extremely clear. The best you can do is get the lowest possible BER, and then you're accurately getting whatever the transmitting radio is sending.

Did you listen to any of the audio files I posted?
 
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#16
With digital, overmodulation happens when the audio is encoded to bits. If the transmitting radio is adjusted such that the audio is being clipped when digitized, there is nothing you can do to fix that on the receiving end. There are some units on some digital systems I monitor that are badly clipped, and others that are extremely clear. The best you can do is get the lowest possible BER, and then you're accurately getting whatever the transmitting radio is sending.

Did you listen to any of the audio files I posted?
How do you change the modulation on the sds100?

Sent from my SM-G965U using Tapatalk
 
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#19
Actually, there is, because AGC isn't even an available setting for the SDS100.

Regardless, I've posted side-by-side comparisons of audio from both scanners using the same antenna and site so you can hear the same transmission as received and decoded by each.
Maybe because the Agc on the x36 never worked. And as for eating the mic, yes different users talk at different levels. Whistler adjusts the volume across p25 to conventional. It levels everything the same loudness. So much so sometimes I can't tell digital from analog. Also squelch tail is handled better! However the Uniden wins the simulcast so there's that..
 

Edka4emk

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#20
SDS 100

Hello All, I am in Seminole County Fl. This scanner works better than bcd992p2 and bcd436hp. I am getting nearly perfect copy on simulcast p25. 100 % satisfied. Highly recommended.
 
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