I recently got back into radio and Out of curiosity I thought I'd check out the various 'bands' supported by EzUHF, I found the 435 to 438 band to be very clean but the 'UK Legal' 459-460Mhz control band was noisey as hell even in the quiet village I live in. I imagine a lot of it is utility company telemetry :|
Interesting! I'll have to check where I am & where I fly!
DaveyLC: do you use a waveband scanner thingy to see how noisy a particular section of the RF frequency is? I was looking at these the other day and they can be expensive especially if you want to go right down to 100s mhz and then up to 4-5ghz.
I've got a dual bander VHF/UHF 2m/70cm that covers the frequencies used by Ez :)
But yeah a super wide band scanner that Goes over 1.3g/23cm will cost you bucks
Really?
Certainly 433 is pretty 'noisy' with all sorts of telemtry going on, but 459 - 459.500 is solely UK R/C airborne use only.
http://www.ukrcc.org/459mhz.html (http://www.ukrcc.org/459mhz.html)
What are you using to scan the frequencies?
I have a Yaesu 817ND and discone and it's pretty quiet.
I also use an SDR (Software Defined Radio) and don't see much around 459MHz.
Cheap Spectrum Analyzer/SDR
http://www.rc-cam.com/forum/index.php?/topic/3891-20-spectrum-analyzer-for-testing-fpv-systems/ (http://www.rc-cam.com/forum/index.php?/topic/3891-20-spectrum-analyzer-for-testing-fpv-systems/)
Nigel.
458-459 comes under RA60 which covers general telemetry
http://www.ofcom.org.uk/static/archive/ra/publication/ra_info/ra60.htm
Devonian: that SDR looks interesting and I have a spare DVB-T receiver (hauppauge USB one) that i could use.
that's interesting!
it was my understanding that 459mhz (or a small bit of it 459-459.5? 458.5-459??)
was for control only in the uk...?
I know that stuff is used either side,
for instance in Yorkshire the air ambulance uses some band @459
and amateur radio too, that's why we cant use 433mhz
I met a chap on top of a hill one day, and he had some radio equipment,
and a book with all registered frequency uses.
that's how I found the air ambulance was very close..
I may try to get the spectrum analyser FW going on one of my olrs rx's
as im intending on using 459mhz a lot this summer.
simon.
The SDR is a great tool.
The 'dongle' has to have the RTL2832u chip and either the E4000 tuner or the R820T tuner.
Personally, I like the SDR# software and the E4000 tuner.
With the Nooelec HF adapter, I can tune all the way from LF through to 1.7GHz in any mode.
A cheap 'radio' and Spectrum Analyzer for not much money.
Nigel.
I must admit immersion's new extreme hopping sounds quite interesting... I think it hops between a 20mhz band rather than the current 2mhz?
Granted by definition its not on the UK legal freqs, but with such wide hopping you'd never be stepping on anyone long enough to cause a problem.
It's funny that this thread has popped up. Over the last couple of days, I have been looking into SDR for testing my 459MHz gear and yesterday purchased a cheap E4000 based DVB-T tuner stick from cosycave.co.uk for £9. Will be interesting to see what that part of the spectrum looks like at our flying field.
Quote from: Devonian on April 15, 2013, 11:22:38 PM
Really?
Certainly 433 is pretty 'noisy' with all sorts of telemtry going on, but 459 - 459.500 is solely UK R/C airborne use only.
http://www.ukrcc.org/459mhz.html (http://www.ukrcc.org/459mhz.html)
Are you sure? The UKRCC link states :
This band is shared with other users, in particular between 458.95 and 459.1MHz. It is recommended that aircraft use frequencies above 459.1 MHz.
That's not an exclusive statement :)
Quote from: Zeeflyboy on April 16, 2013, 12:21:08 AM
I must admit immersion's new extreme hopping sounds quite interesting... I think it hops between a 20mhz band rather than the current 2mhz?
Should be awesome :) and as you say any interference would be almost indistinguishable from random ambient noise :)
Was it also bad above 459.1 - the generally unshared part? It looks very good around me...
If its causing you issues and you can pinpoint it might be worth considering raising issue with local utility. they have plenty of choice. I used to work for one.....l
I'm not fussed as I don't use that band :D
I use a spare Orange OpenLRS RX as a spectrum analyser.. I stay in a reasonably large town.. little or no noise / rf above 459.1 around me..
459-460Mhz
(http://s9.postimg.org/okt2uo0p7/459_460.jpg) (http://postimg.org/image/okt2uo0p7/)
400-470Mhz
(http://s8.postimg.org/96nv3stbl/400_470.jpg) (http://postimg.org/image/96nv3stbl/)
BTW London Heathrow ground ops is on 455-456 and the transmitter is sat nearly 300ft above sea level and kicks out some SERIOUS power :) So hopping around on 20mhz band-width centered on 459 would encounter some issues in that area :D
Oh and talking of legalities I know my EzUHF system didn't come with a CE / R&TTE sticker.. So why do people even bother to worry about which frequencies 'are legal' because we're all breaking the law!
Even if you're using the 100mW EzUHF firmware and a 25mW VTX none of it is R&TTE certified so you're still breaking the same laws :P