SDS200 Detail mode

[Ret_Batt_Chief]

Is there somewhere that describes in better detail some of the display setting in detail mode. RSSI: What are good and bad numbers? Noise: Good numbers. Working on adjusting filters and wondering what good readings are for some of these.

 

[Dog]

Easier to Read SDS100/200 Digital Scanner Manual

 

[dave3825]

The lower the -value the better. So -100 is ok but -65 is better.

 

[KevinC]

Noise- the lower the better. In the tens of thousands is bad.

 

[Ubbe]

It could be tricky to select the best filter. The signal strength meter will react to interference, the more interfered your are the stronger the signal will be. So if anything you should aim for the lowest signal when selecting filter as filters are supposed to block out interference. The noise value are for analog signals but the value will go up when the signal are modulated with voice. The stronger the voice the higher the noise value. So it could be difficult to judge if the noise level went down after a filter change. Perhaps you can use your ears and listen to the background noise behind the voice to tell if the noise level changed.

For digital signals you use the data error indicator D-ERROR to try and get the lowest amount of errors.

If you constantly see RSSI values of -70, or stronger at -60 and up, you can set the attenuator to that system as it will reduce the interference level. Also try to set IFX to a frequency to see if that also helps to improve the signal quality.

/Ubbe

 

[nessnet]

Also of note. Your title says SDS200.
Are you using it as a base or mobile radio?

If mobile, don't get bogged down on filters and IFX.
Both of these are to mitigate (fix) a situation in a specific RF environment (stationary).
They can actually be detrimental in a mobile environment.

When mobile, your RF environment changes as you move about and filter = normal or even off is probably best.
Of course, there are very specific situations where (possible) interference is coming from the vehicle itself, that is another matter.....

 

[Ret_Batt_Chief]

Also of note. Your title says SDS200.
Are you using it as a base or mobile radio?

If mobile, don't get bogged down on filters and IFX.
Both of these are to mitigate (fix) a situation in a specific RF environment (stationary).
They can actually be detrimental in a mobile environment.

When mobile, your RF environment changes as you move about and filter = normal or even off is probably best.
Of course, there are very specific situations where (possible) interference is coming from the vehicle itself, that is another matter.....

Thank you for the info. I am using it as a base. I use my 436HP for a mobile unit

 

[n1chu]

Adding to what nessnet has posted… the filter settings are dependent upon your location. The need (or no need) for a filter could change from room to room in your house. That’s how dependent a filter setting can be on your location. I run one SDS200 at home and another in my vehicle and haven’t found a need to use filters in either. The no filter mobile application is obvious as nessnet mentions, so don’t bother trying to find a filter unless you are spending a lot of time “hill-topping” (stationary and experiencing issues that a filter might correct). If you routinely park at a favorite hill-topping site make sure you use the same parking space each time. (I routinely park in a parking lot every morning, same spot, because it’s close to a WiFi hotspot) and monitor for 3 hours. Having found no issues, I don’t bother with filter settings.)

At home, where a filter setting could be beneficial, I am fortunate to not suffer from simulcast and therefore have no need for filters. (It’s my understanding these filters were originally created for the bench techs back at Uniden (or wherever the design and development process took place) and not included in the options available to the end user. But as simulcast issues raised concerns, Uniden included them with an upgrade to the FW/SW because they found the filters did help with simulcast issues, not necessarily in all cases but it put another tool in our toolbox, one we could experiment with, in an effort to combat simulcast.)

But, bottom line, filters are an option. They are there for you IF you need them. In my case, I was hearing all that I expected to hear and didn’t need to use any filter. So, when Uniden first included the filters I played around with them (at the time there wasn’t much feedback on how they would/should be used or which filter would/could be a winner… just an indication that simulcast issues might be less of a problem when they were used. But as stated, I found no benefit, thankfully. It’s good they are included… I have heard they are benificial.

 

[Ubbe]

At home, where a filter setting could be beneficial, I am fortunate to not suffer from simulcast and therefore have no need for filters.

It's the I/Q demodulator that takes care of simulcast issues. Filters are used to handle interference from adjacent, and not so adjacent, frequencies. That filter have a 10Mhz window that pass all frequencies to the rest of the receiver. Different filter settings move that 10MHz window either up in frequency or down and in different amounts of MHz. The window will always be 10MHz wide so the trick are to find a spot +/-10MHz from your monitored frequency where there are no strong transmitters. If you are lucky to have no other transmitters interfering, and those could interfere if you receive them in a normal way at a -80dBm strength, then you can set the filter to Off which means you are monitoring using the center of the 10MHz wide filter.

/Ubbe

 

[n1chu]

I don’t doubt your explanation of how the filters work but are you saying filters don’t help when simulcast is the problem? True, Uniden never was any good telling us much of anything but didn’t they say the various filter settings could help with simulcast issues?

 

[Ubbe]

I don’t doubt your explanation of how the filters work but are you saying filters don’t help when simulcast is the problem? True, Uniden never was any good telling us much of anything but didn’t they say the various filter settings could help with simulcast issues?

Uniden are not wrong in that statement, as filter settings can help with all kinds of RF receive issues, but are not specific to a simulcast system. If a simulcast system has another frequency in its own system or anyone elses that interfere, then changing filter settings might help.

A signal received at a -60dBm level 1.7MHz higher in frequency will be received at a -80dBm level at your monitored frequency in the 800MHz band and would be a serious interference. Changing the filter type would get rid of that interference regardless of if it is analog, digital or simulcast.

/Ubbe

 

[n1chu]

Ok thanks