Sorry for lack of photos, this was done around 10PM last night, but thought I'd share this with everyone as a bit of help on older tech.
Got a message from someone on our local "Pay It Forward" group regarding a Bose radio that was, in their words, "only producing static". I went & picked this up from them, and got it home, powered it up, and was greeted with the granddaddy of all loud humming noises. At this point I also observed the VFD display was flickering rapidly. This told me to check the filter caps in the power supply.
Opening this unit, I was able to locate the caps to the right of the power transformer. All 3 were Nichicons, dated 1995. The largest one, 10000uF/25V, checked good (Likely for the amplifier circuit).
The next one, a 1000uF/35V Nichicon VR, Tested out so-so (Mind you, using a DMM as I don't know where my checker is), so I swapped this one out.
The last one, a 470uF/35V Nichicon VX, was our culprit. It was leaky enough that my DMM was reading about 4Mohm resistance across it. Replacing this brought the radio back to life.
Just sharing this to show everyone that even the best of the best don't last forever. All replaced caps were dated 1995.
Got a message from someone on our local "Pay It Forward" group regarding a Bose radio that was, in their words, "only producing static". I went & picked this up from them, and got it home, powered it up, and was greeted with the granddaddy of all loud humming noises. At this point I also observed the VFD display was flickering rapidly. This told me to check the filter caps in the power supply.
Opening this unit, I was able to locate the caps to the right of the power transformer. All 3 were Nichicons, dated 1995. The largest one, 10000uF/25V, checked good (Likely for the amplifier circuit).
The next one, a 1000uF/35V Nichicon VR, Tested out so-so (Mind you, using a DMM as I don't know where my checker is), so I swapped this one out.
The last one, a 470uF/35V Nichicon VX, was our culprit. It was leaky enough that my DMM was reading about 4Mohm resistance across it. Replacing this brought the radio back to life.
Just sharing this to show everyone that even the best of the best don't last forever. All replaced caps were dated 1995.
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