Issues UHF Satcom reception

keyhole

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Oct 22, 2016
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18
Location
Germany
The problem: UHF Satcom reception always was very well with Winradio RX. UHF antenna and preamp gave good results. Reception was towards 15W, partly 60 east.I have now moved to a high-rise building on the top floor with a clear view of the east and partly South. Same configuration as before facing east. and now? 0 reception. I can turn the antenna but always bad reception. A bit of 250.55 can be seen. Now, as a test, instead of the PC, I connected a tablet with Airspy to the same configuration and i have a great reception. Tried Airspy on the PC. Zero reception. Only works with a tablet. Does anyone have an answer to this strange behavior?
 

Ubbe

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Sep 8, 2006
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Stockholm, Sweden
How do you receive other frequency bands? Compare tablet to PC. What do you see on the spectrum using Airspy when looking at the UHF SAT band and in other frequency bands?

Problem solving continuos after you know if all frequencies are dead using the PC or only UHF-SAT.

/Ubbe
 

keyhole

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Oct 22, 2016
Messages
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Location
Germany
Reception with PC at 460MHz is ok, but with lot of GSM/LTE, even around 170mhz is ok. only the satcom band. Tablet working fine without interference
 

prcguy

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Jun 30, 2006
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So Cal - Richardson, TX - Tewksbury, MA
You might be getting interference or stronger signals on other frequencies which are overloading the receivers or the preamp. Do you have a band pass filter in front of the preamp for only the UHF satcom range of about 243 to 270MHz?
 

keyhole

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Oct 22, 2016
Messages
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Location
Germany
i dont have passband filter. maybe would be useful. but i dont understand why the reception with tablet is ok...
 

Ubbe

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Stockholm, Sweden
If one control device, the tablet, works fine to receive then it is not the receiver, overload, or intermod or any other RF issue with the actual reciever.

If other frequencies are ok, not degraded at all, remember that uhf-sat are probably the weakest signal you receive, then it has to be a setting that the config in the PC are set to that makes this happen. A gain value or attenuation that are enabled or perhaps a filter in the receiver or if several antenna ports exists it is using the wrong one for that band.

Check your PC's config for the receiver. But confirm that other frequencies are received at the exact same strenght on both tablet and PC.

/Ubbe
 

dlwtrunked

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Premium Subscriber
Joined
Dec 19, 2002
Messages
756
The problem: UHF Satcom reception always was very well with Winradio RX. UHF antenna and preamp gave good results. Reception was towards 15W, partly 60 east.I have now moved to a high-rise building on the top floor with a clear view of the east and partly South. Same configuration as before facing east. and now? 0 reception. I can turn the antenna but always bad reception. A bit of 250.55 can be seen. Now, as a test, instead of the PC, I connected a tablet with Airspy to the same configuration and i have a great reception. Tried Airspy on the PC. Zero reception. Only works with a tablet. Does anyone have an answer to this strange behavior?
I hope you have double checked the sets on both computers for the software (presumed to be SDRSharp or may be HDSDR with the airSpy plug-in. I suspect you have a setting different on one from the other. If not, what happens using other software.
 

keyhole

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Joined
Oct 22, 2016
Messages
18
Location
Germany
i solved the problem. I placed the antenna on another part of the balcony around 4 meter away from last position and now i have good reception. it was the computer and the monitor that caused the interference.
thank you guys
 
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