• You can now help support WorldwideDX when you shop on Amazon at no additional cost to you! Simply follow this Shop on Amazon link first and a portion of any purchase is sent to WorldwideDX to help with site costs.

Cobra 142 over volted on DC power and smoked :(


President CFO & CPFO WorldwideDX Radio
Feb 21, 2011
New Jersey
I have a pretty sentimental 142 gtl that I pulled out to fire up . I had no empty AC plugs in reach at the bench so I hooked it to my 50A power supply and when adjusting the voltage (I run 14.5 normally on exports ) the pot was glitchy and I spiked it with probably 18-20 volts . Now I have no power up on AC and if I try DC the two large coil wound resistors connected to the DC input jack start smoking .The AC power supply is still producing clean 120v power and 13.8 DC on output side . I see no burnt parts or traces so looking for help saving this radio as it was modded and left to me by my pop !

Thanks and 73's
Four-Two-Zero In the Garden State in DX land

Have not had the time to track down the diode suggested will get to it in the morning but need to sleep ! Thanks so much guys and 73's

Hello DX land I am having a hard time finding D407 inside this 142gtl ? I had the flashlight and the glasses on and everything but no luck yet ;( copcicle thanks for reaching out ! I have found a few schematics but they are so blurry I can see the board better ! If I'm being an idiot and I'm not supposed to be looking for a diode please just let me know but ill be "reading the mail" until I find it !! Thanks and 73's Brian
I am not personally familiar with the inside of that radio, but it should be at/near the DC input. Maybe even right across the pins.


Looking back at your original post - check across the smoking coils - that’s exactly where it should be.
  • Like
Reactions: WINKDOGG

Help Users
  • No one is chatting at the moment.
  • @ Crawdad:
    DXMaps has you in SE Wisconsin today BJ
  • @ BJ radionut:
    Say what? :love:
  • @ BJ radionut:
    6m OPEN nicely today...Big Sigs from South Path...band has noise for me last 3-4 days. Not sure what generating this garbage.
  • @ Crawdad:
    Look in your 6m thread BJ
  • @ Crawdad:
    Sorry BJ, just took a better look at it, after cleaning my readers, it wasn't you. Similar callsign.