Loudspeakers, no sound from left Midrange?

Ok 'continuity test' mode should be a diode symbol. When you make contact between the 2 probes it should either display a 1 or make an audible 'beep'.

If you don't have this option available, then a resistor value test should be an alternative.
 
Ok choose ohm it should be ok for a quick evaluation of the breaker.

Then you have to localize the orange and white wires linking pcb to breaker. Check the value between orange and white wire ( either on pcb or directly on the breaker legs). If it have triped you should have a very high value.
Re arm the breaker ( push on its switch) then you test the resistance value: if the reading is now very low value the part should be ok. If it is still very high, you may have find the culprit.
 
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'Mid protector' ( on your first picture) above the mid level ( Lpad).

You should have an orange wire and a white wire ( this one should be bridged to next protector and a third white wire should go back to pcb).
White wire is input, orange is your signal input to mid filter, iow breaker out.
Keep 'service manual' open on page 4/5 it could help identify things.
 
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I removed the wire terminal (1 white, 1 orange) from the back of the mid protector and placed the probes on the exposed terminals.


Reading initially settled down to 1.1


Eventually it went to 0.8


Whilst the probes were on the terminals my assistant pressed the protector reset button several times with no affect on the readings.




I've just performed another reading.


It's settled down to 0.6


Same as the probe short reading.
 
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Ok it is dead. Turk was right.

So to have the mid way working again you just solder orange an white together ( you'll short the breaker/protector for the mid).
This is not very nice solution long term( better to make a bridge on the pcb between white an orange) but for an initial test it will be ok.

If you have heatshrink material protect the soldered wires with it ( or use electrician isolation tape). You dont want the connection to be shorted to anything when testing.

Cliff, what are the loudspeakers pictured in your avatar?
.
 
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What reading should it have given if the protector was OK?


I have another driver lying around which I can use as a test.


After shorting white and orange I'll test using the spare driver for a sound check so as to not expose the original.


Does shorting out the mid protector affect the tweeter protector?
 
Do you have an higher range than 200r? Something in the kilo or mega range? Redo a test with this high caliber: if the breaker is ok when rearmed you should have the same reading as for bare wire, if open ( or busted) you should have the highest reading possible.

Wise to test with another driver first. You only need to know if signal is present.

No it should not affect the tweeter ( they are in parallel: white is the common input from speaker terminal, as long as you have not disconnected the yellow wire on the second protector it is still inline).

I have to go searching kid at school, i'll be back in 30mn in case.
 
This is not very nice solution long term
.


Would these devices be available these days?


If not, is there a modern equivalent which would fit?
 

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Redo a test with this high caliber: if the breaker is ok when rearmed you should have the same reading as for bare wire, if open ( or busted) you should have the highest reading possible.


Firstly, I wanted to thank you.


Test at 2k ohms



Bare terminals reading 001
Probes shorting reading 001


This suggests breaker is OK???


ps: are the terminals on the breaker polarity conscious or are they interchangeable, in terms of white wire and orange wire.


Looks like back to square 1.
 
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I have to go searching kid at school, i'll be back in 30mn in case.


Hi.


Maybe it's the attenuator in the circuit.


One of these???


Also, I must apologize.
Way passed my bedtime, but I think we've progressed significantly thanks to your help.
Can we try again tomorrow?


many thanks


Cliff
 

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