I have a 400A which I bought new in 1980. It has been in regular use since then. Recently one LED in the peak meter display stopped working. I searched this forum and it seems that the fault is with the LED or capacitor which has dried out. Can anyone tell me what the proper replacements are so i can preorder them. I swear I remember seeing a hand drawn schematic for these meters here but I can't find it. If anyone can point me to it I would appreciate it.
is that this schmtc ?
which LED stopped working ?
anyway - as I see it - it's either cold solder joint , or dead OP section , or dead LED itself
in any case - easy to repair
check conductivity of LED with diode test on your DVM ; if not -
check for cold solder joints with magnifier or just reflow all suspicious ones ; if not -
replace adequate OP
which LED stopped working ?
anyway - as I see it - it's either cold solder joint , or dead OP section , or dead LED itself
in any case - easy to repair
check conductivity of LED with diode test on your DVM ; if not -
check for cold solder joints with magnifier or just reflow all suspicious ones ; if not -
replace adequate OP
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400A meter
No Zen, thats not the one. My amp has 2 rows of LED's per channel labelled Peak and Average. The -15 LED is not working on the right channel Peak meter. The - 15 on the average meter ladder is fine. The LED seemed to fail after not using the amp for a month or so. That and the age of the amp are why I thought it might be a cap. I can check the LED and reflow the solder joints but it would be really nice to have the proper replacement LED on hand.
No Zen, thats not the one. My amp has 2 rows of LED's per channel labelled Peak and Average. The -15 LED is not working on the right channel Peak meter. The - 15 on the average meter ladder is fine. The LED seemed to fail after not using the amp for a month or so. That and the age of the amp are why I thought it might be a cap. I can check the LED and reflow the solder joints but it would be really nice to have the proper replacement LED on hand.
LED is certainly generic one ;
if failed - you can always replace it with top most one , and place new ( even if different in glow ) on that top most position
anyway - troubleshooting procedure is same , even if schematic isn't exact one
if failed - you can always replace it with top most one , and place new ( even if different in glow ) on that top most position
anyway - troubleshooting procedure is same , even if schematic isn't exact one
The LED on my NS-10 stopped working - I just replaced it with one I have had around since - ehhh 1980. The original one just had reached its end of life. Just try to solder in a new one.
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