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First off, the three counties do not share one single system. Outagamie and Winnebago do but Brown has it's own. Location and what you use for an antenna will make all the difference in hearing one of these systems or not. I'm in New London and I can't hear Brown county at all. Or Winnebago's control channel for that matter. I can hear traffic from Winnebago county on Outagamie's control channel, however.
Where are you located and what are you using for an antenna? Also, have you programmed it by hand or have you used Sentinel?
My guess is you have very little chance of receiving Brown county in Oshkosh without using an outdoor antenna mounted high. You might even need a directional antenna.
As for Winnebago and Outagamie counties you should be able to receive the Winnebago control channel in Oshkosh with just the stock antenna. And there should be Outagamie talkgroups transmitted on the Winnebago side of the system. Make sure you have all the service types enabled that you want to hear and make sure your location in your radio is correct if you're using location control. Here's a link to an easier to read manual for the 436:
What’s puzzling to me is that I’ll pick up Winnebago and Outagamie on Wiscom every once and awhile but for the life of me can’t pick them up on simulcast,I have gps in the vehicle and all the service types are checked. Also spent some time in Green Bay never did I receive anything from Brown county. They don’t even show on the display, I’ll have to watch the display carefully tomorrow to see if they are even showing.
Yeah that might be the problem you're having. When you're stationary in a building you might be able to receive something if you try setting the radio in different locations or even on its side. With that model you have to try and receive only one tower while nulling out all others. The SDS series don't have that problem. See this article for further reading:
Oh, and the reason why sometimes you can hear county stuff on WISCOM is because once in a while a trooper will select the county patch channels to listen in to what's going on and when their radio affiliates with that tower it will then transmit the county traffic. You'll only hear traffic as long as a trooper is listening to it. Once their radio is switched off that talkgroup, the tower quits transmitting it.
I held the system to Winnebago simulcast and it did show ID scanning also lnk and dat on the bottom but no P25 plus hit good signal strength bars on top. I’ll have to try some different settings as directed by the article or perhaps a different antenna. Thanks for everyone’s help it’s appreciated.