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Hi James,

Thanks for all your hard work.

I may be one of the few users out there that is trying to use your app to coordinate Sennheiser SK50 transmitters along with Lectro gear.

A lot of the frequencies these transmitters use end in odd numbers like 579.795 and so forth.. Is it possible to get an accurate intermod calculation for these? With the current app should i just round off and assume the intermod results for 579.800 will be good enough?

Thanks,

Derek

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While it's not completely finished yet, I am proud to say that I have successfully implemented the FreqFinding calculations (very specifically, testing channel options) on the iPhone gpu, and the results are ridiculous! The speed increase ranges from 200% to 60000% (literally 2.5 seconds down from 2.5 minutes)! It was a bit of a rollercoaster of emotion. Apparently GPUs are incredibly powerful, but utilizing them for general purpose computing means figuring out how to twist your calculations into things that look more like graphics and geometry style computations, and it's even harder with a further constrained mobile graphics platform. It took a number of days of straight staring at a screen on this one problem.

Anywho, what this will mean is more transmitters and I'll be able to put in more models for everyone. Hopefully I'll get the rest finished up tomorrow. Expect the speed boost early next week.

Android folk, you will not be left out in the dark, many of you have the exact same graphics processor as the iphone 4. But there are a few more challenges with android and it's many platforms.

It's going to be great guys.

Cheers,

James

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Hi James!

I've followed the development of this software, and I'm truly impressed with your outstanding work. I haven't used the software yet. I intend to, but, I use the wisycomm system. It's European (Italian actually. Who would've thought. Anyway, If you could incorporate those frequencies, that would be just fantastic. Let me know if I can assist you in any way. Cheers man

(null)

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James, I am not sure if this is too much info for canadian cities and figuring out TV station info, but at this link to the FCC website you can enter cities names in the US or Canada and it tells you all the TV channels active in the area. This might not be what you are looking for, or WAY too much info, but in case it helps....

http://www.fccinfo.com/CMDProFacLookup.php?sCurrentService=TV&sKilometers=100&sLatitude=49-11-10&sLongitude=123-10-25&tabSearchType=Within+Search

Craig

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Hey Craig, the app downloads the station data directly from the FCC database. The FCC has information about Canada's stations that are pertinent to bordering US stations. Those stations are also downloaded by the app. I do not believe that the FCC has a complete database of Canada's stations farther away from the border, however.

Hey Brent, I am sorry. I did not see your reply earlier. You correctly enabled the Station Data part of the app. Afterward the app should have taken a moment to look up your location (you can tell this by the blue arrow in the top right hand of the screen), and then downloaded any station data it could find near your location. If it did find data, your transmitters' frequency will be accompanied by a dB value that tells of the highest power station on that particular frequency. If no data could be found for that location then the field will remain blank. Any time you move more than 20km from the location you last collected data, it will search again (presuming of course that you have an internet connection).

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Hi James,

If the freqfinder app is not able to access my location when I open it how do I know this? Does the db info that existed the last time I opened the app disappear? So if I see any db info displaying signal strength does that indicate that the app was able to locate my

current position?

Have you consideres writing a instructional guide for this app.

Thanks,

Andy

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Hey Andy. The Android system keeps in memory the last known location of your device. While the app does ask for location updates from the system, it will use this saved location if it can't otherwise get a fix. This is so you can turn off your network connection and still be able to use a reasonably accurate location. This also means that if you put your phone in airplane mode and fly across the country, you will be looking at inaccurate dB values. However, as soon as the data connection is reestablished, the system location would update and new data would be downloaded.

I intend on writing extensive documentation on this app, including theory behind the intermodulation phenomenon. However the TV add-on will be much more extensive when it is officially released. There will be no documentation for the TV Preview in the mean time.

Brent, happy to hear it is working for you! Perhaps instead of making Canadians deny their nationality for a few minutes, I'll add Canada to the locale detection and put in the disclaimer that the FCC only contains border line stations.

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Apologies if this question has been answered already but the thought of reading 3 pages of replies to possibly not find the answer was just too daunting!!

Is there a way of saving more than 1 list? I'd like to be able to have a few lists saved in the app for different locations or scenarios.

Also, the app only has about 3 or 4 screens, is that right? I ask because when I was downloading the app yesterday, I had to update my credit card details and I kept getting repeated requests from the app store and some wierdness was going on. I just want to make sure the app downloaded properly and is functioning as it should on my old iPhone 3GS. My phone has the latest firmware installed.

Thanks

Peter Mega

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Peter, 3-4 screens sounds like my app. The ability to save and load transmitter lists is a feature I plan on adding in the future. It does not exist now.

I've hit a weird snag with the GPU accelerated calculations. So far the code works with an ipod touch with iOS5, and it works on all of my simulators. But it does not work on my ipad 2 with iOS 4.3.3. I don't want to update the ipad because I like being able to test on two platforms. Anyway, hopefully I'll figure it out or else I'll just have to revert to non-accelerated calculations on devices that don't work with my code. Sorry for the delay.

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OK! GPU acceleration for iOS devices is on its way to the app review process! It is actually only the first step on that front. There is more optimization to be done I feel. But this will let me revamp the algorithm and open it up to more different types of transmitters.

More things to come!

-James

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Anyone else notice Freq Finder finding problems with Lectro

assigned groups?

In the past, I always used the built in compatibility groups

on my 411a units to assist with coordination.

The other day I noticed Freq finder calls attention to intermod

on channels Lectro says are OK.

(One example: From Lectro block 22, group "c" 45(570.100), 54(571.600), and 64(573.200).

FF calls attention to intermod on 64...)

Glen

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From a UI perspective, maybe a wizard step-by-step approach could work. First the user is given the option to input or select a beginning frequency and end frequency followed by frequencies to avoid (which are highlighted by your Lectro scan) then ask how many intermod channels required before generating a list. The software could automatically space them out automatically (by selecting from alternate ends of the the list of available frequencies). Just a thought.

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The Lectrosonics intermod table does not account for more than 2 transmitters factoring into 1 intermod product. It is true that generating an intermod product between 3 transmitters is more difficult due to the inherent distance between 3 transmitters. And the app only computes to a maximum of 3 transmitters. But that is where the discrepancy lies.

Example: Block 21, Group C 545.100 - 544.500 + 546.000 = 546.600, therefore 544.500, 545.100, and 546.000 will generate a 3rd order product at 546.600.

I will address the slow setup problem. There are just some other higher priority items first.

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I'm experiencing some weirdness after updating to version 1.1 (added hardware acceleration).

Before the update, I had co-ordinated 7 frequencies to use. All were "OK" according to the app.

Since the update, the same freqs, which 5 of now show exclamation points in a red circle on the "TX list" screen.

When I select one of the freqs with the warning and move to the "TX Details" screen, the status shows,

Intermod: Hits Found for like what seems to be a nano second then shows

Intermod: OK

I go back to the TX List screen and the warning is still there.

So, TX list screen shows a warning and the TX Details screen shows OK.

This is happening on all 5 freqs showing the warning on the TX list screen.

The other thing is, (without going through all freqs one by one) I cant find a combination that shows OK on all 7 freqs?

Any one else experiencing this?

New Endian, do you have any idea whats going on?

I'm using the app on my iPhone 3Gs installed with the latest firmware. Everything else on my phone works just fine.

Thanls

Peter Mega

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Hi James,

Thanks for your reply.

Here's the freqs:

Block 29 - 752.400 (64)

Block 29 - 754.100 (75)

Block 22 - 582.600 (C2)

Block 22 - 588.100 (F9)

Block 24 - 638.800 (F4)

Block 24 - 633.800 (C2)

Block 31 - 813.000 (C2) (this Blk 31 is actually my Zaxcom camera link)

Since the last time I opened the app, only the Blk 24 - 638.800 freq shows as "OK", the other 6 show the warning on the the TX List screen but show OK on the TX Details screen.

Thanks James

Peter Mega

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Question for the New Endian...

I live in Halifax, NS, Canada. Out of range for any TV channels to or from the US.

I have one local broadcast digital TV channel on a Lectro block I use in my area - Ch 39 in Lectro block 24 at 620MHz to 626MHz.

I can see it in any 411 scan. Could there be a way for a user to enter Diigital TV channels he/she knows of in their region to FreqFinder, and could the program then take this into account when making its intermod calculations?

I am just setting up the program on gen4 iPod Touch with my system this week.

as part of the annual house keeping/gear checking process.

Just thinking aloud...

Regards,

Jim Rillie

Production Sound Mixer

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