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Help identifying old capacitors

Moonman

New Member
I'm trying to identify the values, in Farads, of the light blue capacitors in the following photos. These are Sanyo capacitors from the early 1980's.

This is a betamax VCR.



20210327_095414.jpg

What does the 1/16 mean?



20210327_095440.jpg

What does the tiny dash in front of the 47 mean?



20210327_095606.jpg

The light blue cap at the back has a small dash, followed by 68.


Remember, it's only the light blue caps I need to identify with a view to replace.
 

JimB

Super Moderator
Most Helpful Member
I have no idea why the little dash is there, but I would say that they are 47uF 16v capacitors, and the one with a 68 is a 68uF 16v capacitor.

JimB
 

rjenkinsgb

Well-Known Member
Most Helpful Member
Point for seven?? just written as .47 rather than 0.47uF possibly??
It's a strange marking if it is.
 

JimB

Super Moderator
Most Helpful Member

augustinetez

Active Member
1st = 1uF 16v

2nd = .47uF 16v (point 47uF)

3rd = .68uF 16v (point 68uF)

And yes that is the correct physical size for such small value electrolytic capacitors - remember, we're talking 1980's tech.

You should be able to find the schematics on the net to confirm.
 

JimB

Super Moderator
Most Helpful Member
OK,
having studied the pics a little more and re-considered the sizes, I agree with 1uF, 0.68uF and 0.47uF.

JimB
 

Visitor

Well-Known Member
Digikey doesn't have any electrolytics less than 1uF. Might be safest to unsolder one of the caps and measure its value.
 

Visitor

Well-Known Member
I'm just saying they are rare, so probably best to verify via measurement than to make a bad guess.
 

augustinetez

Active Member
And depending on what part of the circuit they are in, could probably all be replaced with 1uF - remember, back then electrolytic capacitors had huge tolerances - in the 20 to 80% range (some of today's are not much better).
 

Ken1

Member
Many years ago I repaired several Sanyo color tv's made in 1974 and up and these exact capacitors were used in all of the sets I worked on and Augustinetez and Nigel are correct on the values. In fact I had to replace a .47uf electrolytic capacitor in the AGC circuit of one tv. The tv had a bunch of horizontal white lines in the picture on active channels only. All the lines started on the left side of the screen and extended anywhere from 1/4 to 2/3 across. Picture was normal beyond the lines. It took me a while to figure out the problem and find the defective part was the little electrolytic. I had another used one on hand salvaged from a scrapped set.
 

vtech

Active Member
While the light blue Sanyo caps were famous for drying up, Looks like you have a bit more on your hand than Sanyo caps....
I am very familiar with that era... I can certainly spot the same thing in your posted pix

Pay close attention to the darker areas on the board as you will notice some of the Electolytics have been slowly leaking out.(mostly from the cathode lead). It makes an absolute mess. Not only it is conductive, it is also very corrosive, etching traces and capillaries up the adjacent component legs.--(watch out for the smell as you begin to de-solder). The left-over liquid could easily act like a massive resistor pad under components and you may have to pull components

Look up the series number on the leaky cap and if there are used elsewhere on the board, it is just a matter of time before they will leak and make a mess. If you happen to have an odd servo &/or video problem, it can easily send you thru a wild goose chase.

In US, back in the 80's, many of the Consumer Electronics were plagued with leaky caps.leaky cap.jpg
 

BobW

Active Member
No need to replace them with electrolytics. Just use standard film capacitors. Much more reliable.
 

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