Search found 186 matches

by snn47
Sat Aug 24, 2019 6:53 pm
Forum: Antennas
Topic: antenna related information and guidance for asking questions to improve chances for an answer
Replies: 6
Views: 2624

Re: guidance for asking antenna related questions improves chances for an answer -proposal for a sticky post

@ High SNR
Added your suggestions

@hotpaw and others
Are you proposing to add this information here or as separate post, e.g. Must read on antenna and transmission lines?
by snn47
Sat Aug 24, 2019 10:00 am
Forum: User Projects
Topic: USB HUB Recommendation!!!
Replies: 1
Views: 1520

Re: USB HUB Recommendation!!!

Even if an USB Hubs is shielded it won't help if you use poorly shielded USB cableand if you don't have a consistant shielding from connector to cable to connector, for all devises connected together. In comercial receiver metall boxes are used, which are either soldered cover or have additional con...
by snn47
Sat Aug 24, 2019 9:41 am
Forum: Antennas
Topic: antenna related information and guidance for asking questions to improve chances for an answer
Replies: 6
Views: 2624

antenna related information and guidance for asking questions to improve chances for an answer

Rev.2 2019.Oct.09 Rev.1 2019.Aug.24 I propose to make a sticky post that provides guidance about how to formulate antenna related questions. This makes it easier to no what information is needed, without having to consult a crystal ball if you are lucky enough to have a funtional one. This makes it...
by snn47
Sat Aug 10, 2019 7:47 pm
Forum: RTL-SDR Discussion
Topic: Filters, isolators, bias
Replies: 8
Views: 1738

antennas with limited bandwidth, HP- LP-,BP,BR- Filters, vs. isolators or bias

It depends on the frequency range you want to receive and your RF enrionment, what is the best (affordable) option to reduce interference or in most cases it is overloading of the receiver. Interference are signals or spurious emmisssions that fall within the receiver RF bandwidth. Since RTL-SDR do ...
by snn47
Sat Aug 10, 2019 7:29 pm
Forum: Antennas
Topic: Antenna for encrypted scanner frequencies
Replies: 5
Views: 1873

Re: Antenna for encrypted scanner frequencies

For your understanding: Antenna are passive they don't care about what signals are transmitted or received by the it. It's Transmitter and Receiver that provide en-/decoding of signals. a) its illegal b) there is a reason for why its encrypt c) depending on laws of the country you try to receive suc...
by snn47
Sat Aug 10, 2019 7:23 pm
Forum: Antennas
Topic: Folded dipoles and quad loops with SDRs
Replies: 6
Views: 2135

Re: Folded dipoles and quad loops with SDRs

Those antenna types do not necessarily create a short for the DC path, but It depends on how the antenna is matched to the transmission. But mostly they do, but you can also add a a DC isolation via e.g. a HP-filter.
by snn47
Sat Aug 10, 2019 7:15 pm
Forum: Antennas
Topic: Signal Splitting?
Replies: 17
Views: 3828

Re: Signal Splitting?

As always, if you ask for advice you should explain what you need/want to do. We do not have a crystal ball to find out what you want. This is for you to decide and tell us before anyone can give you an advise. Similiar if you say I need transportaion is a motorcycle or a car sufficient, dou you nee...
by snn47
Sat Aug 10, 2019 10:28 am
Forum: Antennas
Topic: Signal Splitting?
Replies: 17
Views: 3828

Re: Signal Splitting?

Every splitter will attenuate the signal strength coming from your antenna somewhat. The more ports you want the higher the attenuation so you need to add a preamp to compensate the losses.
Search for splitter combiner and you'll find versions with e.g N or SMA connectors.
by snn47
Wed Aug 07, 2019 4:48 pm
Forum: Antennas
Topic: Folded dipoles and quad loops with SDRs
Replies: 6
Views: 2135

Re: Folded dipoles and quad loops with SDRs

Every antenna has a more or less limited bandwidth within which they function well.
Discone and Log Periodic about one octve, other antennas bandwidth depend on the operating frequency. You can consult HAM Radio literature for easy information.
by snn47
Mon Jun 10, 2019 7:33 pm
Forum: KerberosSDR
Topic: Feasibility of a Passive Weather Radar
Replies: 11
Views: 2787

Re: Feasibility of a Passive Weather Radar

For other RADARS look at radartutorial.eu and for the WSR-88D here:
http://www.radartutorial.eu/19.kartei/1 ... 11.en.html
https://www.weather.gov/iwx/wsr_88d