2 radios, 1mic?

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LFD57
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Joined: Sat Mar 22, 2008 8:26 am

2 radios, 1mic?

Post by LFD57 »

Hello everyone. Not sure if anyone has ever done this before but here we go.


I currently have single head UHF XTL5K, and a single head VHF XTL5K. My question is, is there a way to build a switch box of sorts to run only a single mic for both radios. I primarily only use the UHF but would like the emergent ability to use the VHF without having to install a second mic and mount it.
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Bill_G
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Re: 2 radios, 1mic?

Post by Bill_G »

Where would you get the connectors from? That's the hard part.
LFD57
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Re: 2 radios, 1mic?

Post by LFD57 »

Thouht of that too. It's an O5 setup so I think pretty easy, already have a mic extension cable that I could canabalize that.
Jim202
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Joined: Sun Sep 09, 2001 4:00 pm

Re: 2 radios, 1mic?

Post by Jim202 »

I think you could use the accessory connector on the back of the radios if they are low or mid power. If they are high power, use the DB-25 connector. You will have to change the setting in the software if it's a high power to get the external mic audio to work. Then make a switch box to flip from one radio selection to the other.

There is an external mic gain that is set in the radio software. Just make sure you don't get the gain up high as it will bring up all the background noise and cause problems with your mic audio if you get it too high. Use a hand mic from a Spectra and cut off the control head connector from it. Wire the mic into your switch box. You only need to switch the PTT and the mic high line to each radio.

These software settings in the radio do not effect the normal mic operation from the control head.

Jim
Will
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Joined: Tue Sep 04, 2001 4:00 pm

Re: 2 radios, 1mic?

Post by Will »

Spectra mic cords will not solder well, they are the tinsel type.
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chartofmaryland
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What radios do you own?: Alot

Re: 2 radios, 1mic?

Post by chartofmaryland »

Jim202 has it best,

The bricks DB26 on the XTL's work fine as microphone inputs.

Used an 8 pole dual throw switch to a radius microphone and all was well. Just parrallel the wiring to match function and your set.

Program the XTL to disregard HUB or if you require the mic ground you will always be in monitor on your analog resources. Scan will never work right again :( either.
If the lights are out when you leave the station and then come on the second you key up, you know you have enough power.
Dispatch229
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Re: 2 radios, 1mic?

Post by Dispatch229 »

Bringing up a bit of an old topic here, but I think its more appropriate than starting a new thread.

Can I get away with using a standard DPDT switch and only switching PTT and MIC HI (sharing GND and MIC LO)?
motorola_otaku
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Joined: Tue Jan 13, 2004 7:03 am

Re: 2 radios, 1mic?

Post by motorola_otaku »

Probably best not to bridge those leads between radios, as it could create ground loop/voltage difference issues.

Isn't mic audio also available on the DB26 connection on the remote head too?
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