Greetings Badcappers:
--I bought this OCX MODXSTREAM-PRO used on eBay for $35 shipping incuded. It was advertized as working and, indeed it did pass the no load test, with all voltages present and stable. So I proceeded with the teardown, in order to replace the Sus'con caps with good jappers from Digikey.
--Careful inspection, (see pictures) indicated that a roach had caused a nasty ball of hot plazma to carbonize a portion of the board between a schottky leg and a grounded hold down pin. If I had installed this one of my multi drive towers, like as not it would have blown, perhaps taking a lot of other stuff with it. I am surprized it survived the first snap crackle pop. Perhaps that is why the owner decided to flog it.
--I carefully removed all of the burnt material and filled with UV curing green plastic solder mast. I always (see picture) use Mechanic brand solder mast when remasting a damaged area of circuit board. If you do not have a UV light source, you can leave the board in the sun for a couple of hours, or within 1/2" of flourescent light overnight, to harden the plastic. In an abundance of caution, a piece of capton tape insulates the scorch mark on the plastic shield In this case I removed the heatsink holddown in order to make room for a 40mm wide 470uF 450V Nichicon which 5mm wider than the 470uF 409V Sus'con. I included the green mask repair for your information.
--All caps were replaced with oversize and over voltage where possible. And, as you can see, other than a few pieces of rubber and a little liquid masking tape, for insulation insurance, there was no problem getting the larger diameter caps to fit. I will soon be placing a Digikey order to include the 470uF 450V Nichicon filter cap, and when it is installed, I will report back. I have included a list of Cap #s and specs. If anyone knows the number of the 22uF cap, please let me know, as the number on my board was scratced out when removing the white holdown cement. Moderator please remove first two instances of this posting. My apologies.
Cheers
--I bought this OCX MODXSTREAM-PRO used on eBay for $35 shipping incuded. It was advertized as working and, indeed it did pass the no load test, with all voltages present and stable. So I proceeded with the teardown, in order to replace the Sus'con caps with good jappers from Digikey.
--Careful inspection, (see pictures) indicated that a roach had caused a nasty ball of hot plazma to carbonize a portion of the board between a schottky leg and a grounded hold down pin. If I had installed this one of my multi drive towers, like as not it would have blown, perhaps taking a lot of other stuff with it. I am surprized it survived the first snap crackle pop. Perhaps that is why the owner decided to flog it.
--I carefully removed all of the burnt material and filled with UV curing green plastic solder mast. I always (see picture) use Mechanic brand solder mast when remasting a damaged area of circuit board. If you do not have a UV light source, you can leave the board in the sun for a couple of hours, or within 1/2" of flourescent light overnight, to harden the plastic. In an abundance of caution, a piece of capton tape insulates the scorch mark on the plastic shield In this case I removed the heatsink holddown in order to make room for a 40mm wide 470uF 450V Nichicon which 5mm wider than the 470uF 409V Sus'con. I included the green mask repair for your information.
--All caps were replaced with oversize and over voltage where possible. And, as you can see, other than a few pieces of rubber and a little liquid masking tape, for insulation insurance, there was no problem getting the larger diameter caps to fit. I will soon be placing a Digikey order to include the 470uF 450V Nichicon filter cap, and when it is installed, I will report back. I have included a list of Cap #s and specs. If anyone knows the number of the 22uF cap, please let me know, as the number on my board was scratced out when removing the white holdown cement. Moderator please remove first two instances of this posting. My apologies.
Cheers
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