SDS100/SDS200: Modulation on auto sds100

[bmendez]

What does auto do on modulation feature on sds100

 

[wtp]

every band has its own default setting.
that lets the radio do its thing.
it does not change what it picks up.
it should have been called default.

 

[hiegtx]

What does auto do on modulation feature on sds100

every band has its own default setting.
that lets the radio do its thing.
it does not change what it picks up.
it should have been called default.

You can change the default setting used by 'auto' via the Band Default tab in the Profile Editor.

 

[n1chu]

My impression was that “Auto” determined the type of modulation, regardless of which band the radio was receiving, rather a case of listening to the received signal and choosing the correct setting. What drew me to this determination was the air shows I attend. Some of the military flights use FM in a band designated as AM. Of course it could be that being so close to the transmissions just caused the scanner to receive an FM signal while in the AM mode and, because the signal strength was so strong, it sounded ok. So, in my ignorant bliss, I never questioned how the setting was determined, I just assumed my take on the subject was correct. ...Until now. The responses given so far state it’s a default setting, hard set in the firmware that is used when “Auto” is chosen. I’ve programmed my SDS100 to receive the same frequency twice, one set to AM and the other to FM at air shows in the past when I wasn’t sure of the mode used, in an effort to identify which mode to use and don’t recall my results. But hopefully, this year, I will get to try this again.

 

[Ubbe]

The responses given so far state it’s a default setting, hard set in the firmware that is used when “Auto” is chosen.

No, it's not. It's user configurable in the profile section in Sentinel.

I’ve programmed my SDS100 to receive the same frequency twice, one set to AM and the other to FM at air shows in the past when I wasn’t sure of the mode used, in an effort to identify which mode to use and don’t recall my results. But hopefully, this year, I will get to try this again.

Just keep in mind that the SDS100 dynamics in receiver gain are not enough to give undistorted AM reception if the transmitter are close by. Whenever I can hear a helicopter in the air it will be too close to give acceptable AM reception in my SDS100. Other receivers are unaffected and have perfect audio. You probably would at least use the scanners attenuator setting, but I'm not sure if that helps, and you then need to use an antenna that are almost a dummy load, like the Miracle Baby.

/Ubbe

 

[n1chu]

No, it's not. It's user configurable in the profile section in Sentinel.
Just keep in mind that the SDS100 dynamics in receiver gain are not enough to give undistorted AM reception if the transmitter are close by. Whenever I can hear a helicopter in the air it will be too close to give acceptable AM reception in my SDS100. Other receivers are unaffected and have perfect audio. You probably would at least use the scanners attenuator setting, but I'm not sure if that helps, and you then need to use an antenna that are almost a dummy load, like the Miracle Baby.

/Ubbe

I’m not understanding your explanation. Does the scanner revert to a pre-set mode depending upon which band (or portion of a band) you are receiving when the “Auto” option is chosen, as others have posted? Or does the scanner examine the received frequency and determine if it’s an AM or FM transmission, as I assumed? Being wrong more than I’m right, I would guess my assumption is incorrect.🥴

 

[n1chu]

...I shouldn’t have stated the default settings were locked up in the firmware. As you state, they are not. They can be changed by the end user in Sentinel. That much I understood from your reply. But I’d like your take on how the “Auto” option works.