Hello all, I have a Karik that appears almost unused, having been stored since purchase by a collector who recently passed away. Anyway, I opened the unit before testing it, and it looked really clean, no obviously damaged or leaking components, so I plugged it in and got the ”green light blinks a few times and then gives dark”. It didn’t occur to me to open the round-ish PS case. After researching, I found a lot of info that many of you had posted, and it was helpful, to a degree. I did pull the small caps, and they all literally lifted right off their posts and leaked some liquid. the two large caps test fine for 330uF and ESR. Put it back together and still got blinking light for a moment then darkness. I tested all the obvious diodes and resistors, they seem fine., as do Q1-Q3. There is this yellow thing that I gather is some kind of compound capacitor, it says “0.15uF X2 and 2x4700pF Y”. That thing looks like there was an explosion inside it. It’s cracked in multiple places. I was going to order a replacement, which is maybe $15 total, but I don’t know how to tell of this could be the problem, or if I’ll need to order other parts as well. Can anyone tell me what role this thing plays?
Those caps failing are super common and they (the brand and type) have gained that reputation across all makes and models they are used in.
https://www.diyaudio.com/community/threads/densen-dm10-preamp-stinks.337548/post-5782428
They are used to make a filter on the mains input supply, as much to stop interference getting out as well as in very often.
It is VITAL that replacements are the correct type with the X2 and Y referring to the specific safety characteristics of these. You can normally remove them and run the unit without for testing purposes but ideally they should be in place.
https://www.diyaudio.com/community/threads/densen-dm10-preamp-stinks.337548/post-5782428
They are used to make a filter on the mains input supply, as much to stop interference getting out as well as in very often.
It is VITAL that replacements are the correct type with the X2 and Y referring to the specific safety characteristics of these. You can normally remove them and run the unit without for testing purposes but ideally they should be in place.
Thank you, @Mooly. I did pull the thing off the board and re-test. This time the green power light stayed on longer, and didn’t blink, but still faded to black after maybe 3-5 seconds. Any other common issues that you know of that might cause this? I’ve read sometimes it’s best to just replace the Brilliant PSU w/ a non-Brilliant model, but don’t know those are hiding!
I don't know of any issues specific to that model besides what I have seen on here. Those 'Rifa' type/brand of caps were a common problem in pretty much anything.
So it sounds like you have other issues. Caps are always favourites (99.9% electrolytic types the Rifa being a known exception) but I wouldn't normally recommend just a blanket replacement unless they obviously looked deteriorated.
As with anything, a circuit diagram is the first step to trying to fix something like this.
So it sounds like you have other issues. Caps are always favourites (99.9% electrolytic types the Rifa being a known exception) but I wouldn't normally recommend just a blanket replacement unless they obviously looked deteriorated.
As with anything, a circuit diagram is the first step to trying to fix something like this.