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cobra 29

tunercars

Active Member
Sep 12, 2012
84
38
28
a friend of mine picked up a cobra 29 the meter was stuck he replaced the meter and now meter doesn't move but lights up all wires look good and in the right spot he put it on his meter not the best but just need to make sure it was transmitting and it is so what are some things to look for
 

Is there any chance that the needle is trying to move in the wrong direction?

The needle won't travel very far from its zero setting to the left-hand peg, so you have to be watching it carefully to see it move the wrong way.

Polarity matters. If the new meter has the "+" and "-" reversed from the old meter, it could end up wired backwards.

Putting the probes of a multimeter set to 'ohms' to the S-meter's lugs will usually reveal movement from the needle unless the meter is bad.

But only if the polarity of the meter probes is right.

73
 
Is there any chance that the needle is trying to move in the wrong direction?

The needle won't travel very far from its zero setting to the left-hand peg, so you have to be watching it carefully to see it move the wrong way.

Polarity matters. If the new meter has the "+" and "-" reversed from the old meter, it could end up wired backwards.

Putting the probes of a multimeter set to 'ohms' to the S-meter's lugs will usually reveal movement from the needle unless the meter is bad.

But only if the polarity of the meter probes is right.

73
oka when he switched the wires it still didn't work is there anything else that could cause it not to work ?
 
It may not transmit at all, gotta have another radio nearby to listen on the channel you're testing that radio on.

You said the original meter was "stuck".

Ok, before this radio blows up or, gets destroyed further - do you have any antenna connected to the radio so you can even see if it receives - let alone transmit?

Lots of times that stuck needle usually means it got spiked, as in burnt out and the needles' meter movement itself is burnt out or is jammed (jewel movement cup and the needles seat in it are not together) - the tension spring that pulls the needle to the resting spot is damaged. Or unable to pull it back - so that meter is shot and useless to you for now.

How do you know this new one is right for this radio? Ok - if it's identical - then pretty much yes, to a point - don't know if this new one is one that can work in the radio (it may be good, but measures a different power level - which does you no good)

So you replaced the meter with another, and it still doesn't work - so whatever happened to destroy the first meter, is why you're not seeing any signal or results from your efforts so the circuit driving the meter is bad, or the power to work the circuits to show the meter indication - those sections are not working.

This will take several steps including a means to hear what that radio sounds like on another radio tuned to it - I'd start there then assess the situation.
 

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