SDS 200 problems receiving West Simulcast Charlottesville/Albemarle

[john280]

Despite living in Western Albemarle and literally in the shadow of the Bucks Elbow simulcast site, I am only receiving transmissions from the East. When I use the analyze function for the west, I see only signal, nothing else. If I disable the East Simulcast, i hear nothing. Not a big problem since I still hear everything with good quality, just curious as to why this would be.

 

[jkahn]

Make sure you have the correct control channel frequency plugged in for that tower. You might be missing one. Try locking all but that one out, as it may be simulcast overpower

 

[tvengr]

The Albemarle County P25 system can use any frequency as a control channel and will rotate. You must program every frequency in every site.

10 (A)	30 (1E)	5 (5)
010 (A)	030 (1E)	001 (1)
East Simulcast	West Simulcast	Scottsville
Albemarle	Albemarle	Albemarle
851.4375	852.3625	851.125
851.975	852.975	852.425
852.3125	853.0375	854.6375
852.4625	854.9625
852.8875	855.1125
853.8875	857.0625
857.7375	858.0875
858.7375
859.7375

 

[john280]

Thanks for the replies… I used Sentinel to install the system and I’ve manually checked the select frequency screen for East, West and Scottsville. All frequencies seem to be in the scanner. No avoids are set. Not sure if there is something else that I need to check.

 

[tvengr]

You could be suffering from interference from a nearby transmitter. Try using the filters on the West site. Wide invert often works well. You can also try using the attenuator on the West site. The receiver may be overloading.

 

[brianw549]

Had problems with my SDS200 receiving and found that the AGC setting was the problem. The AGC was set to "auto" when I changed it to off the unit came alive. When using Sentinel make sure you are set for SDS scanner under tools then go to edit profile button and a box will open, go to Misc tab and you will find the AGC settings change to no and save file. After this write to your scanner.

 

[tglendye]

Despite living in Western Albemarle and literally in the shadow of the Bucks Elbow simulcast site, I am only receiving transmissions from the East. When I use the analyze function for the west, I see only signal, nothing else. If I disable the East Simulcast, i hear nothing. Not a big problem since I still hear everything with good quality, just curious as to why this would be.

I'm curious if you have taken the unit mobile or to another location? I'm wondering if the mountain could be shadowing the West site signals. Can your SDS receive the West Simulcast sites if you move farther east?

 

[john280]

Had problems with my SDS200 receiving and found that the AGC setting was the problem. The AGC was set to "auto" when I changed it to off the unit came alive. When using Sentinel make sure you are set for SDS scanner under tools then go to edit profile button and a box will open, go to Misc tab and you will find the AGC settings change to no and save file. After this write to your scanner.

Thanks, I’ve gone through your steps, but don’t see any AGC setting option under the misc tab. Not sure why, my firmware is up to date, and I have the target model set to the 200.

 

[john280]

I'm curious if you have taken the unit mobile or to another location? I'm wondering if the mountain could be shadowing the West site signals. Can your SDS receive the West Simulcast sites if you move farther east?

Thanks, that seems like a logical next step. As the crow flies, I’m not that far away from another west tower site on Heards Mountain to my South. I can see it off in the distance from my front door. I’ll pack her up and move east, see what happens.

 

[tvengr]

Despite living in Western Albemarle and literally in the shadow of the Bucks Elbow simulcast site, I am only receiving transmissions from the East.

I'm wondering if the mountain could be shadowing the West site signals

It sounds like OP is looking directly at the site. That is why I believe it is either an interference or receiver overload problem. There may be a number of transmitters on the mountain at that site. Possible cell tower interference: KNKA805.

BUCK'S ELBOW CELL SITE 3.25 MILES NW OF CROZET. ATOP BUCK'S ELBOW MTN.
CROZET, VA
ALBEMARLE County

 

[mc48]

The SDS100-200 do not have an option for Digital AGC, the X36 models do and it's on the system edit page under options.

 

[fredva]

@john280 If it were me, I would try the attenuator that @tvengr suggested. There is definitely some logic in what he's saying. If you are as close to the transmitter as you describe, you may be getting a signal too strong for your scanner to handle. While editing the Favorites List in Sentinel, go to the West site, and change Attenuator from Off to On. Then save the change and transfer it to the scanner. I can't guarantee that will work, but it's easy to do and worth a try.

Also, I don't have the AGC setting either for my SDS-100. I'm confused as to why that was suggested.

 

[tvengr]

I would try the attenuator.

You can enable the attenuator for the West site only. If the receiver is overloaded, multiple transmitters can create a ton of interfering frequencies due to intermod. If you are having interference from other transmitters on the mountain, enabling a filter on the West site can help. Wide invert often works well. I would try the filters first so that you will have full signal strength available when travelling away from the site. You can also enable filters and the attenuator for the West site in the scanner menu to see if it makes a difference before making changes in Sentinel.

 

[brianw549]

Thanks, I’ve gone through your steps, but don’t see any AGC setting option under the misc tab. Not sure why, my firmware is up to date, and I have the target model set to the 200.

Sorry about information I've been working with several different scanners under misc tab turn "Global Attenuator and Global Auto Filter" off.

 

[brianw549]

Had problems with my SDS200 receiving and found that the AGC setting was the problem. The AGC was set to "auto" when I changed it to off the unit came alive. When using Sentinel make sure you are set for SDS scanner under tools then go to edit profile button and a box will open, go to Misc tab and you will find the AGC settings change to no and save file. After this write to your scanner.

Sorry I was working with a different scanner turn off "Global Attenuator and Global Auto Filter" under misc tab.

 

[ScanWV]

I traveled to Charlottesville this past weekend and have the system newly downloaded on my SDS100. I was having the same issues of not able to pick up the West simulcast at all. I was only able to pick up the East. Wasn’t able to do any investigation to be able to change anything.

 

[fredva]

Maybe it's not currently operational? Other than having a control channel.

 

[john280]

I traveled to Charlottesville this past weekend and have the system newly downloaded on my SDS100. I was having the same issues of not able to pick up the West simulcast at all. I was only able to pick up the East. Wasn’t able to do any investigation to be able to change anything.

Thanks for letting me know!

 

[john280]

It’s a new system, fairly recently operational. Perhaps the West isn’t completely operational yet. Anyway, thanks to everyone for all of the suggestions!

 

[john280]

For those of you following this discussion, tonight I clicked on the call sign for the west simulcast, WRFH 243, in RR and compared the list of frequencies to those programmed into the scanner from Sentinel. I found 3 additional frequencies, 851.0500, 853.5625 and 858.8125. I manually entered these into the SDS200 and am now receiving west simulcast on both the new and original frequencies.