SDS100/SDS200: SDS100 Test Results vs Pubilshed Specs.

[KM6CQ]

After reading the multiple postings about the SDS100 being deaf on VHF/UHF.
I would like to know what the FM sensitivity is expressed as uV. What the FM adjacent channel selectivity is, and what the FM 3IMD DR is. I'm interested in Uniden's specifications being compared to a radio that has been privately purchased. If anyone has done this, I would appreciate seeing the results.

Thanks, Dan

 

[mule1075]

Probably would be easier if you bought one yourself and did the tests. If it does not live up to the expectations you would like return it or sell it.

 

[palmerjrusa]

I did a quick comparison between my 436 and sds100 on the aviation band around 130 MHz yesterday. There's no doubt that my 436 is slightly more sensitive here. Tuning to an AWOS frequency (124.875 MHz) and identical settings on each receiver, the squelch opened on the 436 but remained closed on the sds100. When I opened up the squelch the signal was completely readable on the 436 and barely readable on the sds100. My impression is that this is true for other parts of the spectrum as well.

 

[phyberoptics]

I did a quick comparison between my 436 and sds100 on the aviation band around 130 MHz yesterday. There's no doubt that my 436 is slightly more sensitive here. Tuning to an AWOS frequency (124.875 MHz) and identical settings on each receiver, the squelch opened on the 436 but remained closed on the sds100. When I opened up the squelch the signal was completely readable on the 436 and barely readable on the sds100. My impression is that this is true for other parts of the spectrum as well.

Are these results with using the newest firmware released yesterday for the SDS100?

 

[palmerjrusa]

Nope, just realized there's new firmware.
Will update and review again.

 

[AB5ID]

This would being interesting test perform with an FM broadcast band reject filter on the input of the SDS100.

I did a quick comparison between my 436 and sds100 on the aviation band around 130 MHz yesterday. There's no doubt that my 436 is slightly more sensitive here. Tuning to an AWOS frequency (124.875 MHz) and identical settings on each receiver, the squelch opened on the 436 but remained closed on the sds100. When I opened up the squelch the signal was completely readable on the 436 and barely readable on the sds100. My impression is that this is true for other parts of the spectrum as well.

 

[palmerjrusa]

Updated the sds100 with the new firmware.

Don't know if there's supposed to be any sensitivity improvements in that update but a quick check on 124.875 MHz and I swear there's now improved reception at that frequency on the sds100. Will need more time to confirm that though.

Prior to that update, scanning a system in a neighboring state at the edge of reception readability, my sds100 would struggle to pick up transmissions that the 436 would pick up easily.

 

[mule1075]

Updated the sds100 with the new firmware.

Don't know if there's supposed to be any sensitivity improvements in that update but a quick check on 124.875 MHz and I swear there's now improved reception at that frequency on the sds100. Will need more time to confirm that though.

Prior to that update, scanning a system in a neighboring state at the edge of reception readability, my sds100 would struggle to pick up transmissions that the 436 would pick up easily.

Read the release notes there is more than one setting.

 

[palmerjrusa]

Ok, this is just a quick test/comparison (and I did this prior to logging on today and was told there was new firmware). With both radios next to me, the result is now reversed; tuned to 124.875 MHZ, the sds100 now has a more readable signal than the 436.

 

[palmerjrusa]

Ok, want to revise the above.
After switching antennas around trying some other things, think I detect a slight improvement in reception on 124.875 MHz for the SDS100, but the 436 still has the edge here for strength of signal and readability. These are just my impressions though.

Using my SRH789 antenna for 124.875 MHz:

With the SRH789 fully extended, on both radios the AWOS is readable with the 436 having a stronger signal.

BCD436HP: With the SRH789 fully collapsed the AWOS signal is still quite readable.

SDS100: With the SRH789 fully collapsed the AWOS signal is so faint it's unreadable.

 

[K5MPH]

Ok, this is just a quick test/comparison (and I did this prior to logging on today and was told there was new firmware). With both radios next to me, the result is now reversed; tuned to 124.875 MHZ, the sds100 now has a more readable signal than the 436.

This good to know guys thanks for all the info......