[Moved] Help identifying Electrolytic Capacitor

[Karmaboard]

Hi everybody
I own a Geovision GV1120 DVR operating since 2006 24h/24h 7d/7d.
Since some month I experienced degradation on all of the camera images which got worse and worse (see actual picture).

Video problem (Image.jpg)

Already checked all of the other components and the problem is on the card (cameras are OK tested on an external monitor and checked the card on another system and problem is the same).
As changing it would be quite expensive due to changes in standard in the meanwhile (it wouldn’t be enough to change the board, but given new standard and unavailability of the older ones I should change: motherboard, memories, DVR board, 2 I/O boxes, 1 I/O card and I’d lose the analog video output of the original GV 1120 as the new one (GV 1120B) is missing this feature.
Inspecting the board it seems fine (see pictures).

Front (20141117_122948.jpg)

Back (20141117_123029.jpg)

Hoping for the best (changing all of the electrolytic caps solving the problem) I started investigating how to make it.
I don’t want to check the caps desoldering them one by one previously. I’d prefer changing all of them with the new ones on my desk.
Does it make sense?
To start I’m stuck on caps identification.
There are 14 EC all of the same reporting 5f 22 16V. See Image: (GeovisionCap.jpg)


Investigated with the cap’s ID but not sure about it.
Could be 5 pF with 1% tolerance (F) but it makes more sense 22 uF, 16 V is the only clear part.
I’m puzzled. What would 5f stand for? Would tolerance matter or not?
It seems they are aluminum electrolytic capacitors with polymer electrolyte but then I can’t find corresponding ones on digy-key or rs-components.

Is anybody good hearted out there who could lead me to the correct capacitors (even a better one would be very welcome) maybe with a link to an international online seller? (I live in Italy).
I’ve seen also many ‘could be capacitors’ on the back of the board identified as BC on the board but with no id over them. Any idea about them? Capacitors? Likely to fail? Should I care or go straight with changing the electrolyte ones as more failing prone?

 

[milan.rajik]

It is 22 UF 16V and 5f might be batch code or something like that. You can get such capacitors from Nichicon.

 

[Karmaboard]

Thanks milan.rajik, I was able to identify a couple of caps.
I found Series Cj (lowESR) and Cs (long life). While long life is identical in specs 22 uf 16V the low ESR nearest one is 39 uF. Maybe the lowESR could be a better choice given the card (DVR) or it would be better to go for the longlife?

Checked all the caps for continuity and found some with low resistance (ca 80 Ohm) and marked in red.
they are both Electrolytic and maybe Multi-layer ceramic capacitors (???). Most of the small SMD caps (?) (MLCC?) are tied to the big ones, but some groups of them I can't guess anything (I'm not even intermediate in electronics).

Upper side with Electrolytic and MLCC(?)

Lower side with only MLCC(?) marked BC or C


Should be better to get also some of theese smalle caps just in case? Are they prone to fail too?

What should I search for?
Measuring them on the PCB it seems they are around 0.044-0.05uF.

 

[karesz]

If its not too late: I think you are measured some semiconductors (80Ω)with your caps in the circuit, please measure values with in-circuit meters or desoldered, out of board! But dont solder it back, take new ones! There are 47nF, "X7R", ie 25/50V 1206 or 0805 in size_Kemet is one of the best brands. 22uF/16V Alu electrolyts are ie from here to by, but the ceramics too...

 

[pjmelect]

If you don't have an ESR meter, a trick you can do is to remove the capacitor from the board and apply the maximum DC voltage of the rating of the capacitor. You will find in the majority of cases that the ESR is proportionate to the leakage of the capacitor.