Noise Levels in RTLSDR receiver using TA-1 antenna

Currently I am using RTLSDR along with TA-1 turnstile and UHF antenna but seems like the noise levels was high around (-30 dB). What would be the cause for this, is it due to the receiver or the antenna location? It picks up all the stationary radios around the location.

TA-1 turnstile doesn’t receive anything (empty waterfall) in SATNOGS while receives when tracking with sdrsharp giving high noise levels.

UHF turnstile antenna receives good signal in SATNOGS but with other stationary ones in the background of waterfall, while receives signal in sdrsharp as well with high noise levels.

What does this indicate, should it be with the location or the receiver?

Would be kind to get suggestions from the community?

Probably need to know a little but more information regarding the configuration. Do you have an LNA installed, what cabling is used and how much and what are your gain settings for satnogs and sdrsharp.

If you can borrow a VNA it might be worthwhile using that to check the antenna and cabling is good. The TA-1 antenna I think is polarised, but I can’t remember which way it goes, so just watch the lengths around on a good NOAA pass.

It could be local interference. I had issues with LED lighting causing issues on 2M. You might also be near a strong transmitter which is causing issues - filters might help there.

2 Likes

Triple-check the position of your radials, they vary in length and their order matters. I’ve seen the TA-1 underperform for operators before.

2 Likes

There are four radials for TA-1 turnstile on top with two long ones and two short ones. In my setup I have two long ones opposite to each other and short ones opposite to each other. Hope the order is correct?

My setup:
Setup 1) TA-1 Turnstile antenna —> PL to SMA connector --> RTLSDR Bandstop filter --> RTLSDR Wideband LNA --> RG 58 (3 meter) --> RTLSDR --> USB extension (3 meter) --> raspberry pi
Setup 2) TA-1 Turnstile antenna —> PL to SMA connector --> RTLSDR --> USB extension (3 meter) --> raspberry pi

Gain settings was around 30 db in Satnogs and sdrsharp at 49 db.

With sdrsharp tracking NOAA for setup 1 and setup 2 gives NOAA signal with a little change in the pattern of how the actual signal received.
While with SatNOGS, the waterfall is empty even after the verification tests given for empty waterfall in satnogs documentation is done and the tests seems to be okay.

In case of local transmitters, what filters should I use. There is a cellular base station near the antenna at 60 meters. Other than that I couldnt see anything around the location. It could be helpful to get further suggestions from the above details. Thank you.