Spectra A7 Head "mystery switch"

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phillipsc84
Posts: 32
Joined: Mon Nov 20, 2006 5:14 pm

Spectra A7 Head "mystery switch"

Post by phillipsc84 »

Can anyone help identify the purpose of the switch in the picture of the A7 head?

http://www.pwhome.net/misc/CIMG3474.JPG

Anyone who can help I look forward to your replies.
Jim202
Posts: 3610
Joined: Sun Sep 09, 2001 4:00 pm

Re: Spectra A7 Head "mystery switch"

Post by Jim202 »

What switch, all I see is a wire soldered onto the back of the head circuit board.

Jim


phillipsc84 wrote:Can anyone help identify the purpose of the switch in the picture of the A7 head?

http://www.pwhome.net/misc/CIMG3474.JPG

Anyone who can help I look forward to your replies.
Will
Posts: 6823
Joined: Tue Sep 04, 2001 4:00 pm

Re: Spectra A7 Head "mystery switch"

Post by Will »

Jim202 wrote:What switch, all I see is a wire soldered onto the back of the head circuit board.

Jim
Yah, what switch?
Will
Posts: 6823
Joined: Tue Sep 04, 2001 4:00 pm

Re: Spectra A7 Head "mystery switch"

Post by Will »

What I do see is a added red wire from pin 7 and a black wire from PTT. Seems a good way to lockup TX.....

OPPS.. Sorry, Jack IS correct, the black wire IS connected to ground.

So what does the front side look like????
Last edited by Will on Sat Oct 11, 2008 1:13 am, edited 1 time in total.
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jackhackett
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Joined: Tue Jun 10, 2003 8:52 am

Re: Spectra A7 Head "mystery switch"

Post by jackhackett »

I think if you look a little closer you'll see that the black wire (it's a little tough to spot, I didn't even notice it until Will mentioned it) is connected to pin 1 on the mic jack, which is ground.

The red wire appears to be connected to one side of the pads for a jumper. I don't have diagrams for that exact head, but a similar head has jumper spots in that area related to the "VIP out" functions. Since those jumpers aren't normally in, this may have been just a convenient place to pick up an unused connection from the head into the radio, or maybe to the rear accessory connector.

A few questions for the original poster:
Are there any modules inside the radio, or signs that one may have once been there and then been removed?
What type of switch is it, momentary pushbutton, toggle, something else?
Do you know what kind of service the radio was formerly used in? Was it a police radio?
SlimBob
Posts: 911
Joined: Thu Dec 18, 2003 11:38 am

Re: Spectra A7 Head "mystery switch"

Post by SlimBob »

Is the Spectra one of the radios that has to have MIC HI grounded to program the EEPROM?
Will
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Joined: Tue Sep 04, 2001 4:00 pm

Re: Spectra A7 Head "mystery switch"

Post by Will »

SlimBob wrote:Is the Spectra one of the radios that has to have MIC HI grounded to program the EEPROM?
NO
com501
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Joined: Fri Nov 02, 2001 4:00 pm
What radios do you own?: Over 50 - All Motorola

Re: Spectra A7 Head "mystery switch"

Post by com501 »

This looks like an old Transcrypt or Cimarron mod. Look for a scrambler or special signalling board in the radio.
phillipsc84
Posts: 32
Joined: Mon Nov 20, 2006 5:14 pm

Re: Spectra A7 Head "mystery switch"

Post by phillipsc84 »

Sprry for the delayed response. The Switch is just a small togel switch right above the MIC jack. The CH was bought seperately so I do not know any details on teh original radio used with it. Again sorry for the failure to mention that the switch is on the front and the red and black wires are what connect to it.
phillipsc84
Posts: 32
Joined: Mon Nov 20, 2006 5:14 pm

Re: Spectra A7 Head "mystery switch"

Post by phillipsc84 »

Additionaly there do no appear to be any other mods done to this CH. Nothing looks removed or added except for the togggle switch.
WB6NVH
Posts: 270
Joined: Tue Apr 19, 2005 5:08 pm

Re: Spectra A7 Head "mystery switch"

Post by WB6NVH »

There were a bunch of those heads on eBay awhile back; small toggle switch above the mike jack. I think the heads were surplus from the feds...
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