Search found 247 matches

by snn47
Sun May 09, 2021 8:03 pm
Forum: Antennas
Topic: Connecting RTL-SDR V3 on master antenna system in the building
Replies: 5
Views: 505

Re: Connecting RTL-SDR V3 on master antenna system in the building

Even though you will not meassure a voltage when you meassure it with a DVM, you should consider also damage by an Electrostatic Static Discharge, (ESD), when you connect your receiver to the house antenna ports. Only if the receiver is powered by a notebook which is solely operated by it's batterie...
by snn47
Sat Mar 27, 2021 9:09 pm
Forum: Antennas
Topic: UHF (SO-239) antenna bases?
Replies: 6
Views: 1000

Re: UHF (SO-239) antenna bases?

Any mismatch between the receiver, the transmission line and associated components (e.g. connect-or, switches) and the antenna will have some impact on how much the signal from the antenna is attenuated, before it is at the receiver antenna input., but it does not determine if a antenna is providing...
by snn47
Fri Mar 26, 2021 9:49 pm
Forum: Antennas
Topic: Question regarding loop designs
Replies: 9
Views: 6764

Re: Question regarding loop designs

You asked for advice, but choose to not answer questions and ignore facts. As Bruce asked what is the frequency range you want to use it and what frequencies did you do your test on? What loop design did you use, e.g. <1/4 wavelength and tuned, a Moebius based antenn design, or just a coil type ante...
by snn47
Fri Mar 26, 2021 9:23 pm
Forum: Antennas
Topic: UHF (SO-239) antenna bases?
Replies: 6
Views: 1000

Re: UHF (SO-239) antenna bases?

There are a lot of incorrect statements in this reply, the most important is A dipole antenna has 3db gain in free space over a narrow frequency range. Outside of this frequency range the impedance mismatch makes the antenna inefficient. Antenna efficiency meaning how much power of a signal is recei...
by snn47
Sun Feb 14, 2021 12:06 pm
Forum: Antennas
Topic: Best antenna for HF
Replies: 8
Views: 2351

Re: Best antenna for HF

Unless you use direct sampling, yes.
by snn47
Sun Feb 14, 2021 5:45 am
Forum: Antennas
Topic: Best antenna for HF
Replies: 8
Views: 2351

Re: Best antenna for HF

In short: There is no antenna that provides you good reception, especially at HF with this dimensions, because you can't beat physics! You can receive with everything, starting from a wet noodel cooked in salt water, a 1 ft nail for VHF and a few meter of wire for HF. If it conducts it will receive....
by snn47
Sat Feb 13, 2021 10:43 am
Forum: Antennas
Topic: Log-periodic antenna for UHF
Replies: 4
Views: 1296

Re: Log-periodic antenna for UHF

Depends on the type of feed line. If you have a symetrical feed line like a chicken wire (two parallel wires spearated by some form of plastic), you don't a Balaun at the antenna but at the end when you convert to a coax system, this is why early TV had the Balaun inside the TV-receiver at the symet...
by snn47
Sat Feb 13, 2021 10:34 am
Forum: Antennas
Topic: Can anyone recccomend an antenna ?
Replies: 1
Views: 535

Re: Can anyone recccomend an antenna ?

No one can answer your question if you do not provide the bare minimum of information e.g. specify your "small antenna" in relation to the frequency range you want to receive, is it (omni-) directional, where did you place it indoor, which floor, are the walls steel reinforced or outdoor, on ground ...
by snn47
Fri Dec 25, 2020 8:38 pm
Forum: RTL-SDR Discussion
Topic: RTL-SDR up to 6 GHz via a Harmonic Mixing- can frontend modifications improve sensitivity?
Replies: 0
Views: 689

RTL-SDR up to 6 GHz via a Harmonic Mixing- can frontend modifications improve sensitivity?

Tuning an R820T2 RTL-SDR up to 6 GHz via a Harmonic Mixing Driver Hack provides information about an softwarehack that allows to to use the 5th harmonic on R820T2 RTL-SDRs to receive frequencies above the normal 1.766 GHz limit https://www.rtl-sdr.com/tuning-an-r820t2-rtl-sdr-up-to-6-ghz-via-a-harmo...
by snn47
Tue Dec 22, 2020 6:44 pm
Forum: Antennas
Topic: Self-building my first dipole antenna
Replies: 1
Views: 751

Re: Self-building my first dipole antenna

Have you looked at "antenna related information and guidance for asking questions to improve chances for an answer"? In addition coaxcable- Balauns and Ferrite-Baluns there are other versions to achive balanced to unbalanced feedin, just check amateur radio websites for building a 10 m dipole and in...