Frequency Scanners

[cedd]

From reading that write-up, it would appear the software is for programming and config only. Whether it would allow some purpose made software to be written is another thing.

 

I love the line "This scanner is also useful for finding hidden transmitters in bugged rooms". Something I'm sure is high on everybody's agenda when buying a scanner.

 

I might briefly add that whilst prosecution is highly unlikely, you do actually require a license to receive many of the frequencies these things can pick up. Look at the number of people still using scanners at airports and air shows, and you'll see how little notice is paid to it, but it's a little known fact.

 

0.1Mhz is really rather low! What are we talking there? Marine LF?

[mackerr]

As others have said, WinRadio is probably what you saw in action. There is a version of the WinRadio hardware that is compatible with the Shure Wireless Workbench software, which will allow you to scan outside the Shure bands. The Aaronia Spectran is also OK if you use it interfaced to a computer, although it acts more like a scanner than a spectrum analyser. Without the computer, the Spectran is useless, the display is unreadable without a jeweler's loupe.

 

Mac

[cedd]

Resurrecting an old thread here!

 

I spotted these online at work today and wondered if people might find them any use? The software's got everything there, but without the aesthetics of winradio. It's also a fair bit cheaper! They also offer a developers kit to write your own software, so you could do a specific, simplified version just for radio mics.

 

Signal Hound

 

It looks to have a pretty decent spec. Nice wide dynamic range, covers all the frequencies we'd want. Generally looks like a pretty able piece of kit for (comparatively) not much money.

[Simon Lewis]

Cedd,

 

Would you be able to comment on how well the RF spectrum analyser in Sennheiser's Wireless Systems Manager compares to a dedicated frequency scanner? Obviously, one wouldn't expect perfection, but for the bands of interest, it looks reasonable?

 

Simon

[cedd]

Not really if I'm honest Simon. My use of the Sennheiser software has been pretty brief and it wasn't on my kit - I'm a Trantec user.

 

From what I HAVE seen of the Sennheiser software, it's very good. I'm not 100% sure how quickly it sweeps. I have a feeling it'll be pretty slow, which won't help you find short "splats", but it's perfectly fine for other forms of interference.

 

One thing that does impress me is that it'll work for VHF, Ch38, Ch70 and even up to 2.4GHz stuff. You'd need a different Sennheiser receiver per band in UHF, so that's 2 needed to do the job properly, and that doesn't sort out VHF and 2.4GHz.

My idea of this is to run it alongside my existing systems while they're in use. Using the Sennheiser software would take one mic out of action, and would only cover the frequency range of that receiver.

I guess for most people, in short, yes the Sennheiser software would do fine. Before this I was toying with buying just a receiver in ch38 for just such a function, but it's only about double the price to get a fully featured and (if you believe the specs) very able little spectrum analyser.

 

I actually own a spectrum analyser, but it's the size of a small house and certainly isn't what you'd call portable. It also drifts like nobody's business and needs to have been turned on for at least a decade to be stable! No crystal oven luxury!

 

Of course what you really want is the toy we've been using (borrowed) at work recently - a Fieldfox spectrum analyser. These are the things you'll see the guys from Ofcom walking round with when they're hunting for interference. Very able little toys! Work won't buy me one though :-(

[Shez]

I spotted these online at work today and wondered if people might find them any use? The software's got everything there, but without the aesthetics of winradio. It's also a fair bit cheaper! They also offer a developers kit to write your own software, so you could do a specific, simplified version just for radio mics.

 

Signal Hound

Linked from that site is some software called PAWS4400 (short for Pro Audio White Space finder). Used in conjunction with that Signal Hound, it looks like a pretty good package. A quick play with the demo suggests it'll monitor a user-defined band and show you in real time what's going on. It can monitor up to 20 frequencies for signal strength and let you know if any fall below a specific threshold. Will also work out intermod-free frequencies based on the measured RF environment.

$1500 for the receiver, software, antennae and pelican case. Anyone tried it?

[Matt Pengelly]

Linked from that site is some software called PAWS4400 (short for Pro Audio White Space finder). Used in conjunction with that Signal Hound, it looks like a pretty good package. A quick play with the demo suggests it'll monitor a user-defined band and show you in real time what's going on. It can monitor up to 20 frequencies for signal strength and let you know if any fall below a specific threshold. Will also work out intermod-free frequencies based on the measured RF environment.

$1500 for the receiver, software, antennae and pelican case. Anyone tried it?

 

As a combined analyser/IM calc, that would be a very attractive price indeed.

 

I've been umm-ing and ah-ing over a PSA1301T combined with something like IAS from Professional Wireless for frequency co-ordination duties this past few months, but I'd be mega happy keeping it all within the one program on a nice big laptop screen (and not having to worry about spares/support for the Palm element of the TTi down the line!).

 

My only concern would be that there doesn't seem to be a way to build-up (or ideally, import) a profile for pre-existing wireless systems in the way that IAS can. Obviously every manufacturer and even models within a manufacturers range employ different RF technologies and so getting reliable IM calculations that take into account model-specific filter and intermod spacings might be a bit hit and miss. Or at the very least yield lower useable frequency sets. Or am I completely wrong in thinking that? I'd love to be corrected though as I don't claim to be an RF guru (pun intended) by any means.

 

I've also been talking to the chaps at http://www.oscium.com/ about adapting their existing 2.4GHz-range analysis iPhone app and creating a hardware dongle that looks at the UHF ranges we would be interested in. I think it could really open things up to get a simple, accurate, zoomable analyser running on an iOS device. You would still need IM calc software, but you could save £100s. They've already told me they think it's possible and are keen to hear from more people in our field who might support such a project, so if that's you then please head over to the site and use the contact form to drop Bryan Lee there a note saying so!

[Matt Pengelly]

Just by way of an update...

 

I downloaded the PAWS4400 software on a demo license and had a play around.

 

It certainly has some potential, but at the moment I felt like it didn't quite come up to scratch on either the analyser or the IM calc fronts.

 

Possibly it's just that I have been brought up in a generation of iPhones and DAWs, but the fact that there is no easy way to zoom in and out of the on-screen SA trace I found massively annoying. The 'region of interest' thing is clunky at best. It's also a shame that while you can define a trace range and a centre frequency, you seem to be unable to make the viewer step up and down in preset blocks, which is how I like to use SAs; hopping up and down in 8MHz steps (when I'm in the UK...!) so that I can examine each channel in turn and make sure it is doing what I expect it to be.

 

The IM calc section seemed to do a decent enough job, albeit I would like to see a little more scope for setting up preset models in the way that I can in IAS. A Sennheiser G2 pack does not exhibit the same IM filter characteristics as an Shure SLX pack and likewise a 2000 series is not the same as a PSM900. I think it would be hard to come up with a frequency plot that you could put your name on when the software assumes all things are created equal. Best case scenario you end up missing out on perfectly good frequencies and worst case, well that's obvious!

 

It also seems way to expensive for what it is at $1,500 all-in. A copy of IAS Basic and a TTi can be had for similar money and for a couple of hundred more gets the Professional IAS package. The one saving grace of the Signal Hound/PAWS4400 setup being that I can look at 2.4GHz range stuff as well. I'm not really sure how useful that is though given I can achieve that with other equipment and for a fraction of the price.

 

To that end I've come full circle and have just today placed an order with Professional Wireless and TTi.

 

There is definitely a market for this though I think, once they make it a little more user-friendly and bring the cost down!