WinRadio and Workbench

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Brad Harris

Sophomore
Mar 1, 2011
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Aquired a WinRadio WR-G33WSM for the last leg of a tour to use with Shure Workbench 5 to handle 8 Senn G3 ears, 2 UHF-R handhelds, and 2 ULX instrument packs.

Worked out pretty well for the run, do a waterfall plot during setup, in the time I've gotten all the mics plugged in, it's ready to tell me what to set the frequencies at for the day through the compatability tool.

In the documentation (release notes - known issues), it mentions that the frequency display with the WinRadio unit is offset by 2 step sizes (ie, 25kHz step size, its offset by +50kHz).

Knowing this on tour, it was always in the back of my mind going into areas with alot of rf traffic, specifically, are the frequencies Workbench telling me to avoid, is that the actual frequency? or is it off by the offset? (ie, is it actually 525.450mHz that is says, or is it 525.400mHz?). This might be trivial, but I'd like to know.

So with some slight downtime the past day, I've put up a wireless handheld set at 550.000mHz, fired up Workbench and found that it would say that it thinks it is anywhere from +0.075 to .125mHz offset (all within the same step size - .025mHz), and it would be the same offset regardless of step size (ie, it was always .075mHz regardless of step size).

This would happen (same offset) for each time workbench was restated, and would only change when you restart Workbench.

Any thoughts?


BRad
 
Re: WinRadio and Workbench

And, with 2 different frequencies, it shows 2 different offsets.

2 UR handhelds, 520.000mHz, 550.000mHz

Synthesis thinks they are 520.025mHz and 550.100mHz respectively.


BRad
 
Re: WinRadio and Workbench

Not being fluent with the WWB or WinRadio, the best course of action would be to rent or borrow a known good spectrum analyzer or frequency counter and perform a series of measurements with both the WWB/WinRadio setup and the known good system and compare the results for a pattern. It would seem to me that any system with a known error not corrected with subsequent software or hardware fixes is not to be trusted.
 
Re: WinRadio and Workbench

Some more down time today with workbench.

Setup:
2 computers running Workbench v5.0.5.2
1 connected to a UHFR, the other using WinRadio WR-G33WSM
4 UR1 belt packs tuned to 520.000, 540.000, 550.000, and 570.000

Results:
WinRadio shows more interfering frequencies which Workbench doesn't interpolate as intermodal frequencies. BOTH UHfR and the WinRadio show different amounts of offset from the actual frequency (.025 to .100mHz), which leads me to believe it is WorkBench that has the issue, not the WinRadio receiver.

The WinRadio software does not have any offsets and hasn't shown any error.

So a new question, how much error is acceptable? I'm all for spending an extra 5 minutes to scan with the WR software, and manually enter in On Air Frequencies in WB Synthesis, but if .100mHz of error is acceptable .....


BRad
 
Re: WinRadio and Workbench

100kHz is not acceptable at all, it's roughly half the bandwidth of a transmitter. Any offset leads to errors in the IM calculation. The big problem is different offsets for different frequencies, so calculation is off by more than 100kHz.

I would always spend the extra 5 minutes to get accurate data.

Thanks a lot for bringing this into attention and further examination.
 
Re: WinRadio and Workbench

Brad Harris said:
Results:
WinRadio shows more interfering frequencies which Workbench doesn't interpolate as intermodal frequencies. BOTH UHfR and the WinRadio show different amounts of offset from the actual frequency (.025 to .100mHz), which leads me to believe it is WorkBench that has the issue, not the WinRadio receiver.
Click to expand...

Please define what you call "interfering signals" and "intermodal frequencies".

If the WinRadio is showing IM products due to mixing (what I guess you're calling "interfering signals"?), that WWB through a UHF-R does not, that's a function of the WinRadio front end not being as selective as the UHF-R's.

If by "intermodal frequencies" you mean harmonics, then you're overloading the front end of the receiver. Reduce the input until only the fundamental and product frequencies remain.

In either case, any scanner or spectrum analyzer (and I use that term very loosely) that can not accurately show the true frequency within +/-50Hz (and even that's not a terrific spec), should not be used. Transmitter frequency error alone will vary from a couple of hundred to a couple of thousand Hertz.
 
Re: WinRadio and Workbench

The problem is in Shures software (WWB5) I brought this to their attention quite a while ago. And don’t look for it to be fixed in WWB6 if that is ever released. I have been told it doesn’t support the WinRadio. At least to start with.

And in the documentation it does mention the input sensitivity that you must be aware of.
 
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