Absolute beginner (in nappies / diapers)

[sdclee]

Hi there.
I have used an IOS App called WebSDR which appears to be an internet equivalent of the SDR USB + Arial option (?) in that you can tune in to all sorts of radio over the internet using the waterfall view.
As yet I know little about radio so would like to ask a few simple questions before I consider buying a kit like this for example:

RTL-SDR Blog V3 R820T2 RTL2832U 1PPM TCXO HF Bias Tee SMA Software Defined Radio with Dipole Antenna KitRTL-SDR Blog V3 R820T2 RTL2832U 1PPM TCXO HF Bias Tee SMA Software Defined Radio with Dipole Antenna Kit

So hopefully you'll contribute to my questions and forgive me if I should have created this post in a different forum.

1) Where I live in the hills in the North of England there is little or no reception for FM, so how will I know whether an SDR kit will work with any of the wavebands (I appreciate the basic differences between AM/FM/SW etc)?
2) Would the dipole antenna kit be sufficient for general use or would I have to consider a more advanced arial (possibly roof mounted)
3) Some of the Youtube videos I have watched ignore Linux and concentrate on Windows but I assume there's plenty of open source software that will work with any SDR USB dongle (?) I do have access to a Windows 10 machine if I have to stick to that at least to start with.
4) Is there a better starter kit than the one I mentioned above?
5) What advantages would I have using an SDR Dongle over the internet's WebSDR app?

Many thanks in advance for any contributions.
Cheers.

[G4ZFQ]

This group https://www.rtl-sdr.com/forum/viewforum.php?f=1 is good for RTL advice. There are lots of examples for beginners on its main pages https://www.rtl-sdr.com/ and https://www.rtl-sdr.com/rtl-sdr-quick-start-guide/
(This one is not really for general questions, is for SDR-Radio SDR software. Which you may use for RTLs.) Obviously any questions regarding problems using the RTL with this software will be attempted here.
Web SDR is OK if you do not want the bother of setting things up and are not concerned that you are not actually receiving anything.
Alan

[sdclee]

Many thanks for the prompt reply and the information provided - you see, I was caught out straight away because I didn't even spot that the "RTL" (brand specific) might have me in the wrong place.
I'll head over to the locations you suggested.
Many thanks again.

[KA1GJU]

Do yourself a huge favor, get a 'real' SDR that is really plug n play, versus the RTL dongles that require loading drivers using Zadig and hoping everything will work!
Yes, and Airspy HF+ costs much more than the RTLunits... but the damn thing works out of the box! I leave the RTL units for my ADSB RXR server for FlightRadar24 using a Raspberry Pi, and gave up on using them for general RXing after two days. They just suck, IMHO.

Plus the Airspy HF+ works VERY WELL with SDRC (SDR Console) and I have 7? of them operating as SDRC servers on various antennas for myself, and Internet users. The best antenna I have found for HF usage is an EFW (End Fed Wire) as long as you can make it (+120' or more!) matched with a 9:1 UNUN at the feedpoint. Grounding the UNUN gave me about 1.5 S-units lower noise floor on the low bands BTW! Mine are as far away from the house as possible, and I am using old aluminum CATV (75 ohm) 1/2" hardline removed from poles when fiber replaced it. Some of my runs are +300' of coax! But getting the antenna out in the woods away from QRM makes for nice listening on HF! I have electric cattle fencing around and underneath my antennas, but with attention to keeping the lines from touching tall grass, branches, trees... It's hard to 'see' or 'hear' the pops on the scope, but I can see the neighboring three farm's fences at 1/4 to 1/2 mile away!

Spend the extra money on a real SDR, and you won't be disappointed vs the marginal performance of the RTL units.


73 Kriss KA1GJU
Home of the Super Station SDRC Servers in NH, USA!

[sdclee]

Wow! Thanks for the reply most of which is way over my brain’s antenna to be honest.
I will digest it all again when I have done some more reading.
I appreciate it.

[KA1GJU]

Your Airspy dealer in the UK:
https://moonrakeronline.com/airspy-hf- ... re=default

Don’t forget RF adapters to go from what ever antenna coax you eventually end up with to the SMA on the Airspy!

73 Kriss KA1GJU

[jdow]

With regards to antennas, for HF if the noise in the receiver increases you have sufficient antenna on that frequency for your needs in that you cannot cheaply improve on performance. Above some frequency around 28 to 150 MHz the random length wire concept loses its allure. Basic atmospheric noise becomes low enough that tuned antennas can do better than the random wire most of the time. Wide band "compromises" such as Discone antennas give adequate but not stellar performance over quite some frequency range. Anything else will have frequencies on which it performs well and frequencies on which it performs poorly. The ARRL Radio Amateurs Handbook is a good place to scratch the surface in the fascinating world of antennas if you want to dig more.
{^_^}

[sdclee]

Thanks for the reply. I'll go on the hunt for the book

[sdclee]

Now I should have looked before posting, so apologies.
There are scores of editions of the book (The ARRL Radio Amateurs Handbook) and there are multiple volumes.
Q1) it appears to have many references to 'American' but does that really matter (I am in the UK)?
Q2) is an earlier edition such as the 3rd edition 1965 any use or completely out of date? - The 2020 version looks voluminous and expensive

Don't forget I am a novice wishing to take baby steps by first asking you good folks for pointers.
Many thanks.
L
ee

[jdow]

1965 is OK. I am sure RSGB has something equivalent. We all gotta start somewhere. I found the ARRL handbook (1956ish edition?) quite helpful for my bootstrapping in the 1958-1959 time frame and for some time afterwards. Then I hit more specialized books and one thing led to another including college degrees. You can stop when your brain saturates, of course. A basic idea of what is going on is always helpful and the basics never really grow old.

When reading most any beginners book it often helps to realize that the "ground over here is not the same as the ground over there." The space and traces between them on the PCB is also a circuit element. The ideal circuits are nice for wrapping your mind around the problem. Then when you try to implement the little details get in the way. "Ground" is one of the first concepts learners should reexamine.

And as far as antennas go, if something conducts it radiates. If it radiates it receives (usually but not always on the same path as it sends.) All an engineer can do is negotiate with this with regards to efficiency and directivity. In that negotiation always remember you cannot get more out of an antenna than you put into it when transmitting. All you can do is sort of gather up power going "over there" and find a way to shove that power out "over there." Sometimes that is very useful for bringing up weak signals or blocking (nulling out) interference.

Much of what appears in the beginners books and amateur level handbooks is idealized with a good dose of hands on experience without great gobs or even much in the way of little tidbits of heavy math. After all, you CAN do a serious lot with rules of thumb and experience. (And little enough of the very basics has changed that I still consult Terman's old book I scored at a college bookstore back in about 1963 from time to time, and not just for the memories.

It helps to admit that learning is often a painful and difficult process; but, there is no better "high" in this sorry world we inhabit than "having learned" and using that knowledge. That's my drug of choice.

{^_^}