SDS100/SDS200: Busted Remtronix 820S? (SDS100)

lowvaluetarget

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I am getting almost no reception, or weak reception on my new Remtronix 820S compared to the one that came with my radio. 800Mhz P25 Trunked system.
That's not right is it? The stock rubber duck is outperforming the 820.
 

tvengr

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I suspect that the receiver is being overloaded due to the additional gain. Try the filters on the site to see which one works best. You can also use IFX on the site frequencies if a local powerful transmitter such as an FM radio station, TV station, or NOAA weather transmitter is causing interference. Try turning on the attenuator to see if reception improves on the 800 MHz system.
 

lowvaluetarget

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I suspect that the receiver is being overloaded due to the additional gain. Try the filters on the site to see which one works best. You can also use IFX on the site frequencies if a local powerful transmitter such as an FM radio station, TV station, or NOAA weather transmitter is causing interference. Try turning on the attenuator to see if reception improves on the 800 MHz system.
Attenuator seemed to fix it. Thanks!
 

tvengr

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I would try the filters and IFX before the attenuator. Using the attenuator will reduce the range on the 800 MHz system. The increased 800 MHz level may be causing intermod problems with other transmitters in your area. The filters will also reduce interference from other transmitters.
 

lowvaluetarget

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I will when I get some time. The deal was I was getting zero decode on p25 with the 820s before attenuation and now it's crystal clear with a -80RSSI. Is the 820s that good where it was overloading the receiver?
 

tvengr

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The REM-820S antenna gives much higher gain than the stock antenna on 700-900 MHz frequencies. The fact that turning on the attenuator improves your reception verifies that the antenna's additional gain is causing your problem. If you have any cell towers nearby, the antenna will increase the signal level of them also. Excessive signal level can desensitize the receiver. When the receiver is overloaded, it increases intermodulation problems where signals can beat together with each other and produce other interfering frequencies. The filters are designed to pass what you want to receive and attenuate other frequencies. Turn the attenuator off. Try all of the filters on each site giving you problems and use the one with the best decode. Avoid the use of the Auto filter. That runs through all of the filters to find the best one every time you scan a site and really slows down your scanning speed. I often have good luck with the wide invert filter. If the filters do not solve the problem, use IFX on the frequencies in a site. Use the attenuator only as a last resort. It will reduce your receiving range.
 
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