Problem with remembering values between case structures - shift registers - tunnels

[Insiderbe]

Hi, 

After a few days of searching without luck i'm hoping someone can help me.

I'm building a PMR446 receiver that automatically jams the received signal in the band 446.00625 MHz to 446.09375 Mhz ( analog walkie talkie)

using a peak detector, I want to determine the specific channel / frequency to jam, the VI then needs to remember this value and use it in the next case (transmit)

The problem is that it won't work, it says " wire connected to undirected tunnel" or "missing assignment" using shift registers....  

It's probably a beginners mistake, but i hope someone can fix it 🙂

thanks in advance

[crossrulz]

I think your problem is you still have the frequency control still wired up.  You should just delete that control.  You will also need to use Index Array to turn that array of frequencies into a scaler (single value).

[Insiderbe]

That's correct, the control was a part of the problem 🙂
The shift register works with a CONSTANT value ( see: 446 006 250 Hz )

But how can i choose the biggest value from the "array of frequencies" if i can only input an index ( the corresponding value ( 0 to 10 for example) for the respective frequency ?)

From the 1D array i need the biggest amplitude and corresponding frequencie, so i can use this frequencie in the transmit case
I use the peak detector but it won't choose the biggest value... 😕

[GerdW]

There's an ArrayMinMax function, which gives you both max and index...

[crossrulz]

Why don't you just use the Extract Single Tone Information.vi?  That does the FFT and returns the strongest frequency.

[Insiderbe]

Thanks , the Array Min&Max works, partly 😮

I'm sorry to bother you guys again :s But the detected frequency and amplitude is totally different from the real frequency ?

i made a simple peak detection receiver, with the an FFT spectrum viewer and the 2 options to compare: a "peak detection" and an "extract single tone".

Why isn't it giving the values I want?
-> the amplitude should be in dBm , not 0.5 :s
->the frequency should be in actual frequency : 446.00625 MHz .


This is one of the last phases of my project, i would be really gratefull if this worked 😛