RTL-SDR.COM Wideband Amplifier (Real World Results?)

[dlwtrunked]

Thank you for your evaluation and encouraging response.

The whole building is full of RFI sources. For example: IIRC, there are over 30 WiFi access points and many LED lights to conserve energy.

I hope to take my laptop, SLM, and antenna outside for some measurements.

Years ago, I did a comparison of different LED light bulbs RFI and submitted and article to QST of the results. That article was rejected with "we will not discuss why or further on the topic". I found that response incredible- particularly since I myself have edited sections of professional technical journals (a special section Optical Engineering and was often a reviewer for them in general) and such practice is considered unacceptable. I later spoke to a later president of the ARRL and he himself was was shocked. There were noticible difference between the different makes. I use LED bulbs only on light intermittantly in my house but incandescents on the main living room and kitchen lamps. I have a annual check all wall warts for QRM on my to do list. If I had a dollar for each of these in the house, I would be rich I may use the HackRF1 Portapak for that.

Taking a lab top outside seems an excellent idea to compare. I normally keep one of my AirSpy R2 in the car with an old Toshiba. I have used that a lot in tracking down signals of interest--particularly in your direction as I go out to Wallops to watch launches (I live in Fredericksburg). My worst QRM problem is the neighbors' new washing machines on Saturday mornings.

 

[jonagra]

I'm fairly new to the SDR scene, so forgive my ignorance...
I've had a Nooelec SMArTee for about 2 years now, and I'm just now finding out what a bias tee is.
I've been running my SDR occasionally over the past two years, every time with it just being connected directly to my antenna without a LNA. My question is, is it safe to do this with 5V going directly to the antenna, given it's not a shorted antenna?

 

[rabbit108]

My question is, is it safe to do this with 5V going directly to the antenna, given it's not a shorted antenna?

It is my understanding that the biasT is always on in that model. However, it does have a protection circuit in the event of an intermittent short but not a continuous short. If you are certain that there is no DC short from the antenna, you are probably OK. If you change antennas or have doubts, you might consider a DC block that will block DC but allow RF to pass. A DC block usually consists of a capacitor in series with the center conductor.
https://www.nooelec.com/store/dc-block.html