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Cobra 89xlr
- Thread starter Ben Hebert
- Start date
Robb has shown you the area to examine.
Good Luck, stay safe, and best regards.
Where are you testing the + voltage at?
Where is the - lead of your voltmeter connected?
Right out of the bridge rectifier, you should see about 20v. Look/click on at that schematic I posted earlier, as it shows the voltages. You may have a bad xformer if you don't see 20v. You might have shorted caps in there too. It might also be one of the zener diodes or one of the transistors. Going to have to test them all wherever the voltage falls off from what the schematic calls out for.
Power supplies like this one are fairly simple. Conquer it; I can see that you are no quitter. BUT be very careful of the AC side - don't even bother to test that side - please! 22vac is coming out of the xformer and going into the bridge rectifier, so there should be a 1.6v drop down to 20v. After that, the rest of the voltages are on the schematic.
Where is the - lead of your voltmeter connected?
Right out of the bridge rectifier, you should see about 20v. Look/click on at that schematic I posted earlier, as it shows the voltages. You may have a bad xformer if you don't see 20v. You might have shorted caps in there too. It might also be one of the zener diodes or one of the transistors. Going to have to test them all wherever the voltage falls off from what the schematic calls out for.
Power supplies like this one are fairly simple. Conquer it; I can see that you are no quitter. BUT be very careful of the AC side - don't even bother to test that side - please! 22vac is coming out of the xformer and going into the bridge rectifier, so there should be a 1.6v drop down to 20v. After that, the rest of the voltages are on the schematic.
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Sure thing, run it off 12-13.8v @ least 2 amps. (fused)
That is how I am running a "band-aid-base" right now.. Just leave the 110v plug hang loose and unplugged.
Oh ok cool. Yeah it has to be the voltage reg is bad everything that need power has power just about half of what is suppose to have
Cool. Me too. I have one spot on the main board not getting any power should the brown wire from the pa switch have voltage to it?