SDS200: SDS 200 Crackling Transmissions in the 450-485 mhz

Nascar18

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I have a brand new SDS 200 and having really bad crackling after transmissions in the 450-485 mhz band. The scanner is connected to a Stridsberg multicoupler. I tried using the ATT on the UHF channels and finding some difference. Do I need to return the scanner to Uniden?
 

MStep

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I have a brand new SDS 200 and having really bad crackling after transmissions in the 450-485 mhz band. The scanner is connected to a Stridsberg multicoupler. I tried using the ATT on the UHF channels and finding some difference. Do I need to return the scanner to Uniden?
Before considering any cold solder joint (or other technical) issue, I would disconnect the Stridsberg multicoupler and try the unit with just the included telescopic or connected directly to its own outdoor antenna, preferably with different cables.

If the unit still proves to be problematic, I would return it to the dealer from which it was purchased for a refund. It's a brand-new unit and should not have to go back to Uniden right out of the box.
 
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tvengr

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Are these conventional frequencies or trunked frequencies in a site? Are they analog or digital. Are some frequencies in that range working OK? Please let us know what you are trying to monitor.
 

Ubbe

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I have a brand new SDS 200 and having really bad crackling after transmissions in the 450-485 mhz band.
If it is a digital frequency then send it in to Uniden. If it's analog then there are different filter settings to try that will change a whole department of frequencies. You also have the IFX setting. If it changes when the attenuator are on then it's probably some sort of radiofrequency interference. If you monitor the same frequency with your 996 with open squelch, then you can't hear anything in the background that could interfere? Listen with the SDS200 with open squelch to hear the background noise and compare to 996. If all the filter and IFX are tested without making any difference then it can be some components failure, otherwise it's the RF environment that are too problematic for the SDS200 and could need some external filters, maybe a stop filter for a strong transmitter frequency.

/Ubbe
 

Nascar18

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They are all conventional frequencies and analog. Anything trunked or digital is fine. I sent a new file without the ATT on and took the Stridsberg multicoupler off and it is better. I have the filters off. I did notice with my 996 some noise after transmissions on a few channels. Could the Stridsberg be overloading the SDS 200 in the UHF band?? I do have power going to the Stridsberg. Am I better off unplugging it?
It's my first experience with a Stridsberg multicoupler.
 

Ubbe

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I have a Stridsberg but doesn't use it any more as it overloads too easily and its specification isn't that great compared to a $20 amp and $10 CATV splitter,, and then I live in a valley surrounded by hills and more or less only receive reflected radio signals.

Try at least the filter in SDS200 set to Normal and then Invert. Then stop scan on the problematic frequency and do Function+7 to toggle IFX on.

/Ubbe
 

Whiskey3JMC

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I have a brand new SDS 200 and having really bad crackling after transmissions in the 450-485 mhz band. The scanner is connected to a Stridsberg multicoupler.
What do you have as an antenna at the other end of the multicoupler? No other bands aside from UHF affected?
 
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