Author Topic: Audio Isolator pcb for Conductor  (Read 7773 times)

Offline RJ

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Audio Isolator pcb for Conductor
« on: May 10, 2013, »
We found that some audio devices like certain transmitters and speakers can cause a ground loop issue on the conductor leading to it doing everything from rebooting to skipping to not working at all. The sparkfun audio decoders output is not setup to run powered items but only headsets. It will work fine on some setups. My Ramsey and dell computer speakers work fine but some don't.

As a fix the people making the chip in the sparkfun module provided a little simple circuit of 2 capacitors and four resistors to isolated the outputs. We have had it tested with setups that just plugging in the transmitter caused massive issues and it resolved it. So I had a bunch of very small pcbs made for this. You simple cut you audio wires in the middle and hook the ends to this circuit board. The ground on the audio of the conductor pcb get hooked to the Trigger ground instead of the audio ground. Then shrink wrap or tape the pcb to keep it from shorting out in the case.  In future conductor pcbs I will add these parts to the conductor itself so the extra little pcb will not be needed.

I am putting the pcbs in the store so anyone needing them can get them coming. We believe we are close to releasing the updated Conductor firmware soon. You can get the two 100uf caps and the four resistors at radio shack we checked.

RJ
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Offline rdebolt

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Re: Audio Isolator pcb for Conductor
« Reply #1 on: May 10, 2013, »
Thanks RJ! I had no issues with my Ramsey, but by any chance were people having issues with  EDMs?

Offline RJ

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Re: Audio Isolator pcb for Conductor
« Reply #2 on: May 11, 2013, »
I do not remember the one that I know was a problem but it was in a post.

RJ
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Offline travailen

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Re: Audio Isolator pcb for Conductor
« Reply #3 on: May 11, 2013, »
I had no problems with my EDM.

Rick S

Offline Mickpat

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Re: Audio Isolator pcb for Conductor
« Reply #4 on: May 11, 2013, »
Thanks RJ!  I had issues with my fm transmitter so hoping this will help.


Offline keitha43

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Re: Audio Isolator pcb for Conductor
« Reply #5 on: May 11, 2013, »
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Thanks RJ!  I had issues with my fm transmitter so hoping this will help.
Which transmitter were you using? I saw reports of dagco transmitters causing problems with conductors possibly due to their high output. They make the mobile black box transmitter.
« Last Edit: May 11, 2013, by keitha43 »

Offline Mickpat

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Re: Audio Isolator pcb for Conductor
« Reply #6 on: May 11, 2013, »
Something like the following: 

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Works really well, but had to move it far away from the conductor to work.  If it was too close, the conductor would stop playback.

Offline keitha43

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Re: Audio Isolator pcb for Conductor
« Reply #7 on: May 11, 2013, »
Makes sense then as it looks like that has more output than what is "legal" in the US for a home transmitter. The Mobile Black Box is also uber powerful. I heard one for miles before. His antennae is on a 70' tower  :)

Offline sittinguphigh

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Re: Audio Isolator pcb for Conductor
« Reply #8 on: June 16, 2013, »
Not sure about this.
Will the conductor work straight into amplifier and speaker setup ?
Or will I need a update hardware and software?


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Offline caretaker

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Re: Audio Isolator pcb for Conductor
« Reply #9 on: June 16, 2013, »
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Not sure about this.
Will the conductor work straight into amplifier and speaker setup ?
Or will I need a update hardware and software?
Yes it will, the conductor has a line level output so connecting it to an amp with speakers is equivalent to connecting it to a transmitter.
Jeff Squires
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Offline animal

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Re: Audio Isolator pcb for Conductor
« Reply #10 on: June 16, 2013, »
You might need some kind of preamp to get the voltage up to drive the power amp. Something like a small mixer. This will give you tone controls and volume. Line level won't be enough to drive the power amp to full voltage.

  animal.

Offline zwiller

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Re: Audio Isolator pcb for Conductor
« Reply #11 on: June 19, 2013, »
I found the output of the conductor to be loud and I bet it would "work" if that's OK with you.  You could test with a mp3 playing your setup and see if you like it.  Audible but not hifi.  I second animals suggestion for a small mixer to be the best solution. 
Sam, who is happy he flashed his etherdongle with newest firmware!

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Offline typoagain

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Re: Audio Isolator pcb for Conductor
« Reply #12 on: November 10, 2013, »
I thought I would order and build a couple of these just to keep on hand incase I ever need them.
Why not? They’re cheap enough.
But I could not find what parts I needed to order. I realize that I can probably get them locally, but I was putting in a Mouser order anyway . . .
One of the new guys in Odessa TX.

Offline mkozik1

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Re: Audio Isolator pcb for Conductor
« Reply #13 on: November 10, 2013, »
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I thought I would order and build a couple of these just to keep on hand incase I ever need them.
Why not? They’re cheap enough.
But I could not find what parts I needed to order. I realize that I can probably get them locally, but I was putting in a Mouser order anyway . . .

2 10K Resistors
2 100 uf Caps
2 100 ohm Resistors

Take a look at the PCB image attached



- Mark

Offline typoagain

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Re: Audio Isolator pcb for Conductor
« Reply #14 on: November 12, 2013, »
Great! Thanks much!
One of the new guys in Odessa TX.