A5 head just DIED I need help!

The General forum is where users can discuss any topic regarding Motorola communications equipment - hardware, software, etc. There are also several focused forums on this board, so please take the time to ensure that your questions doesn't fall into one of those categories before posting here!

Moderator: Queue Moderator

Post Reply
jake6758
Posts: 34
Joined: Fri Dec 30, 2005 4:24 pm

A5 head just DIED I need help!

Post by jake6758 »

Hi,

I jsut had my A5 Spectra radio head die. I will first say I just installed a 450-470 3.8dB/5dB Dipole antenna with a 50 foot LMR-400 cable, for this radio.

Kinda weird the screen dies Right after I install an antenna. Someone told me that the antenna may let power back into the radio and that that had something to do with it.

any ideas? PLEASE help! I dont want the same thing to happen when I replace the head.


Thanks Jake
jake6758
Posts: 34
Joined: Fri Dec 30, 2005 4:24 pm

Post by jake6758 »

Sorry i should say its JUST the screnn and Lights buttons still work. I can still hear the radio beep when I press a button or transmit.
Jim202
Posts: 3610
Joined: Sun Sep 09, 2001 4:00 pm

Post by Jim202 »

By any chance did you try pressing the dim button on the control head? Sometimes the button gets hit when your not thinking about it. The button is easy to press by accident. You should have 3 positions. Off, dim, bright if I remember correctly. I leave mine in high normally so forget how many steps there are.

Jim
jake6758
Posts: 34
Joined: Fri Dec 30, 2005 4:24 pm

Post by jake6758 »

Hi, yes I tried that, and I took the head off my VHF and swapped them the head from the UHF still does not work after pressing DIM many times the XMIT light comes on if I trnasmit but the backligthts wont come on either
User avatar
kb0nly
AKA: The Computer Doctor
Posts: 3370
Joined: Tue Apr 01, 2003 1:15 am

Post by kb0nly »

When you swapped the heads did the one from the UHF work ok on the VHF radio though?? Just wondering if it's actually the control head at fault.

My gut feeling is no.. If you tried a known working head from another radio on it and it still didn't work then you have another problem with that radio.
Duct tape is like the force, it has a dark side and a light side and it holds the universe together.

"I Reject Your Reality And Substitute My Own!" - Adam Savage
jake6758
Posts: 34
Joined: Fri Dec 30, 2005 4:24 pm

Post by jake6758 »

Sorry If I was not clear

UHF radio > Head with bad screen and backlights
VHF radio > Head in 100% working condition.

If I take the head of the UHF and put the head from the VHF radio in its place the head works. If I put the head from the UHF radio on the VHF radio it still does not work.

Jake
User avatar
kb0nly
AKA: The Computer Doctor
Posts: 3370
Joined: Tue Apr 01, 2003 1:15 am

Post by kb0nly »

Ahhh ok. So what we are dealing with here is just a bad head. If the display and the backlighting isn't working is everything else? I know you mentioned the TX indicator comes on, does it also switch modes and does the volume level adjust and so on?

It might just be a failed power supply in the head. Pretty common with their capacitors that are prone to failure.
Duct tape is like the force, it has a dark side and a light side and it holds the universe together.

"I Reject Your Reality And Substitute My Own!" - Adam Savage
jake6758
Posts: 34
Joined: Fri Dec 30, 2005 4:24 pm

Post by jake6758 »

Got a new Head......

Thansk for the help!
kc7gr
Posts: 1031
Joined: Wed Mar 13, 2002 4:00 pm
What radios do you own?: Motorola, Icom, Sunair (HF).

Before you toss that other head...

Post by kc7gr »

You may want to check the bad head for leaky electrolytic caps, specifically the two 10uF/50V aluminum critters. If you see discolored solder joints or an irregular blackish-gray stain on the PC board, around where the caps are mounted, chances are pretty good they're your culprits.

Check quickly, though. The electrolyte they used in those beasties is very corrosive over time. Left to itself long enough, it will literally eat through the board.

Happy cleaning.
Image
Bruce Lane, KC7GR
"Raf tras spintern. Raf tras spoit."
Post Reply

Return to “General Motorola Solutions & Legacy Radio Discussion”