ASTRO SPECTRA W3, Strange Background noise while XMITing

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26M10
Posts: 57
Joined: Sun Jun 16, 2002 4:29 am

ASTRO SPECTRA W3, Strange Background noise while XMITing

Post by 26M10 »

I have a strange noise in the background of my W3 Astro Spectra.

It sounds like FSK data in the background of my transmitted audio.

Anyone ever heard of such a thing?

I have even pulled the unit out of the truck and put it on a bench supple..It does the same thing.

Analog or Digital mode...Makes no difference
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mr.syntrx
Posts: 1587
Joined: Wed Apr 28, 2004 10:09 pm

Post by mr.syntrx »

It's not the weird trademark W3 noise is it, around 400Hz?

If you open the HHCH, you'll find two wires from the mic element to the PCB. They cross the path of a small IC. Try moving the wires out of the way with your fingers, put the head back together, and see what happens.
26M10
Posts: 57
Joined: Sun Jun 16, 2002 4:29 am

Thanks

Post by 26M10 »

I will check that right now.....

It would probably be around 400Hz

I actually have two W3s..I will try and swap the HHCHs first.
26M10
Posts: 57
Joined: Sun Jun 16, 2002 4:29 am

Post by 26M10 »

mr.syntrx wrote:It's not the weird trademark W3 noise is it, around 400Hz?

If you open the HHCH, you'll find two wires from the mic element to the PCB. They cross the path of a small IC. Try moving the wires out of the way with your fingers, put the head back together, and see what happens.
Mr.Syntrx -> Ask what thou wilt for thou are found the wisest among your companions.

This is what is was..

I opened the HHCH and there it was the red and black wires from the MIC element went right over (and were touching) that IC.

I moved the wires and put a small piece of Kapton tape on it and voila.

Quiet as a mouse.

Thank you so much.....

DD
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mr.syntrx
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Joined: Wed Apr 28, 2004 10:09 pm

Post by mr.syntrx »

No probs, nice to see the problem's solved.

I can't really take credit for the fix though, I read about it in an ASTRO primer written by a former board member, who is a pretty clever bloke. It's fairly common though, and Motorola still haven't figured it out for themselves, either :)
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4n6inv
Posts: 410
Joined: Wed Jan 19, 2005 7:39 pm

Post by 4n6inv »

There evidently was also a grounding issue with the mic element. I came across some retro-fits kits to solve the problem on Flea-Bay and bought them. I haven't read the literature completely, but it sounded like a similar issue with the background noise.
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