Minimoog Electrolytic Cap replacement tolerance?

The Moog Forum Moog Music General Topics Forum
1

I’m restoring a minimoog for a friend and was looking to match the exact ratings of the original components.

All the electrolytics are listed as -10% tolerance. However most of the availability seems to have -20% tolerance.

Are -10% rated caps the only replacement? Will using -20% caps cause tuning or other problems?

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thanks in advance,
-Allen

http://www.myspace.com/tempustry
http://www.cdbaby.com/tempustry
http://www.myspace.com/allenbrunelle

2

ok, I came across this capacitor substitution guide, so I guess its one of the golden rules.
(full guide here: http://www.niccomp.com/help/capsubguide.asp )

Substitution Rule: A component with a tighter (better) tolerance can replace a looser tolerance component
i.e… ±1%(F) tolerance part can replace ±2%(G), ±5%(J) or ±10% (K) tolerance part
i.e… ±2%(G) tolerance part can replace ±5%(J), ±10% (K) or ±20% (M) tolerance part
i.e… ±5%(J) tolerance part can replace ± 10%(K) or ±20% (M) tolerance part
i.e… ±10%(K) tolerance part can replace ±20%(M) or +80%/-20%(Z) tolerance part
i.e… ±20%(M) tolerance part can replace +80%/-20%(Z) tolerance part

3

Caps of higher tolerances (10% or better) are best sourced from Mouser or Digikey here in the US. Look at the temperature rating also, especially on caps in the PSU. 85 degrees is standard, 105 degrees is higher quality and longer life.

4

how important is it to recap an old mini?

5

it’s very important, I’m disappointed nobody is chiming in. :frowning:, maybe its too self-evident.

6

If these are power-supply caps, which it looks like, and which almost all electrolytics will be, the exact value doesn’t matter. These caps are must better quality and smaller than they were back when the Mini was built. You could probably put in a cap twice the value in the same space, which would make the power line even quieter. The new cap probably has a lower ESR (look it up), which will help also.

Just make sure you put it in the right direction - or boom!

7

this little lot should do the job, yeh?

http://uk.rs-online.com/web/

Stock No. Qty Unit Price Goods Value Description

108-5440 10 £0.34 £3.40 030 ASM Al Electrolytic Cap,63V,2.2uF
108-5462 10 £0.33 £3.32 030 ASM Al Electrolytic Cap,63V,10uF
226-6921 3 £1.09 £3.27 PEG124 axial Al electro cap,100uF 25V
226-6937 4 £1.56 £6.24 PEG124 axial Al electro cap,220uF 25V
226-7003 2 £2.41 £4.82 PEG124 axial Al electro cap,470uF 63V
226-7019 2 £3.29 £6.58 PEG124 axial Al electro cap,1000uF 63V

and one of these:

http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=170185981988

8

Can any on tell me if there is a list of alternative Capasitors to replace them on boards 2 and 4 as all mine have cracked. I know that some are 0.01mf, 1mf and 0.33mf but not sure if some are coupling capacitors or voltage caps.

9

[quote=“tempustry”]
"All the electrolytics are listed as -10% tolerance. However most of the availability seems to have -20% tolerance.

Are -10% rated caps the only replacement? Will using -20% caps cause tuning or other problems?"

Does anyone know the answer? I have located a good supply of +/-20% axials in Canada…but I am not sure if they will work. Or if there actually are these 50/-10% electrolytics still manufactured, or available in smaller lots from major suppliers? What are some other alternatives should we be unable to find axials with this tolerance?!

Thanks in advance for any help on this one! This seems to be one of the most significant restorations we can do and yet I am completely confused about supply.