| Author |
Message |
    
Polecat
Junior Member
Username: Polecat
Post Number: 16
Registered: 2-2007
| | Posted on Friday, April 13, 2007 - 1:36 am: | 
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Hi All;
Long story short, a trucker friend gave me a nice, clean little TRC 483 40 ch mobile, that he removed in 2004 (supposedly working)
I hooked it up to a 12 volt power supply and no power, checked and found a blown fuse, replaced fuse and then when i hooked it up to the positive side i saw a slight spark (arc)the radio was switched on but did not light up........
Anyway i knew something was amiss and when i checked the leads with an ohmeter the ground is OK but the positive (red wire) also goes to ground when i touch the chassis with the other probe.
I thought the leads may be grounding out where they enter the radio (no plug on these) wired straight in....but there is no short there.....
So i'm wondering where along the line to the switch is this 12 volt lead is groundimg out?
Odd one eh? any help appreciated, hate to toss out a nice little radio....no techs in my area
Thanks; |
Kabar
Junior Member
Username: Kabar
Post Number: 25
Registered: 6-2003
| | Posted on Sunday, April 29, 2007 - 9:50 am: |
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There should be a protection doide on the circuit board just inside the radio near where the power cord enters the radio.
Look for this diode and check for damage to it. |
Barakuda318
Intermediate Member
Username: Barakuda318
Post Number: 147
Registered: 2-2002
| | Posted on Sunday, June 24, 2007 - 5:12 am: |
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The diode on the 483 is located in between were the wires solder to the board and were the power regulator is mounted, it will most likely be burned or cracked, simply cutting away this diode will solve the problem but will no longer provide circuit protection, replacing the diode is the best way to go, I used to know what diode it was but it escapes me at the moment... |
Hotwire
Senior Member
Username: Hotwire
Post Number: 2269
Registered: 1-2005
| | Posted on Sunday, June 24, 2007 - 11:12 am: |
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Yes the protection diode! Reverse polarity burns it out. I believe it is on the foil side of the board and it will look burnt. Sometimes the trace will even curl up. Good idea to replace the diode because your not sure what exactly is going on in there. This is a common repair in these brand of radios so I hope we hit the nail on the head! good luck
Kenny
cef491(27.115lsb)
2sf491(27.555usb)
Indiana
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