Blackgate F series 680uF 65v!

Just ordered some Blackgate F series 680uF 65v from
ebay (Indonesia) US$ 10/pc. Later read that these are
very old BG like 15 to 20years. I want to use them to
update the PS stage of my LM3886 based amp. I cannot
go back in the purchase, but some suggestion regarding
usefulness/danger/practicality of using them would be
helpful. Also what kind of precaution should I take as they
are very old?

Thanks
Roushon
 
Hi Roushon,

I don't know about the longevity of these particular electrolytics but I often use electrolytics that are several years' old. Before using them I go through a modified reconditioning process that I found described in a Panasonic capacitor datasheet some years ago. The process is to charge the capacitor to rated voltage slowly (through a quite high resistor value) and then let it stay at the maximum voltage for a minimum of a half hour (often more). Here's an excerpt from a Panasonic HFZ datasheet:

5. Long Term Storage
Leakage current of a capacitor increases with long
storage times. The aluminium oxide film deteriorates
as a function of temperature and time. If used
without reconditioning, an abnormally high current
will be required to restore the oxide film. This current
surge could cause the circuit or the capacitor to fail.
Capacitor should be reconditioned by applying rated
voltage in series with a 1000 ohm, current limiting
resistor for a time period of 30 minutes.

Personally I use a higher value than 1 kohm (about 100 kohm for 1000 uF) - just to make sure.

Best regards,

Jesper
 
Thank you!

Hi Jesper,
Thank you very much for your reply. One
question regarding the charging voltage. I will be using
them to smooth a +-45volt supply and the caps are 65v.
So, what voltage supply should I use for the reconditioning? Is it OK with 45v and a (say) 68k resistor?

Thanks and regards
Roushon.
 
Hi Roushon,

My guess would be that you could use 45 VDC but I usually charge them myself to their maximum voltage. In this way I know they've been reconditioned to at least the voltage I'm going to use them at. And, yes I think 68k would be fine but probably would use a 150k myself and then also apply the voltage slowly from low to higher ;-)

Good luck with them ... BTW I once had some Blackgate F or FKs I think and used them in an amplifier I built. Whether it was due to the Blackgates or the design as such I don't know - but the bass and overall rhythm/drive was was speedier & tighter than anything I've made before - or after.

Regards,

Jesper
 
I hope you know that you can buy similar (even fan boy product!) caps from Digikey for much less than $10 per.

I did not know that there are caps similar to BG.
I am reading and reading about better caps for Audio for quite sometime and everywhere I am directed to BG caps. So it was buried in my head that BG should be tried. Do not know if it is a debatable subject.

Thanks
Roushon.
 
FYI if anyone is interested: Partsconnexion still has BGs which I assume are not fakes:

Blackgate Electrolytic Capacitors F Series

Jesper

Thanks Jesper! I could have saved some dollar if I knew this before. But
shipping from USA would be more than Indonesia I think, so it compensated. I did check Parts connexion but that list was outdated....Hoping the caps I purchased are genuine.....Thanks again for your concern.

Regards
Roushon
 

Pano

Administrator
Paid Member
2004-10-07 6:05 am
Panama
The Blackgate is a pretty good electrolytic cap for most uses. They were a big fad for a few years. FWIW, you can get better caps, new, for less money. Try the Panasonic FM and FC series (FM if you can). Great specs, well made, not expensive, low, low ESR. Digikey has them.

Oscon caps are also quite good.
 

Jay

Banned
2003-02-11 9:02 am
Jakarta
Just ordered some Blackgate F series 680uF 65v from ebay (Indonesia) US$ 10/pc. Later read that these are very old BG like 15 to 20years.

Also what kind of precaution should I take as they are very old?

I don't think Black Gates are that old (less than 10 years ago I could still buy original BG). Especially these "new version" of Black Gates. Personally I think they are fakes. Whichever the case I believe it is safe to use them for your power supply.

For power supply I use two types of Black Gate F. The 1000uF/35v and the 680uF/65v for higher power supply voltage. The 1000/35 has "K" motive on the top of the can. The 680/65 has "8" motive. I was disappointed when I purchased a lot of 680/65 from a friend, and found out that it was not as good as the 1000/35 .
 
I don't think Black Gates are that old (less than 10 years ago I could still buy original BG). Especially these "new version" of Black Gates. Personally I think they are fakes. Whichever the case I believe it is safe to use them for your power supply.

For power supply I use two types of Black Gate F. The 1000uF/35v and the 680uF/65v for higher power supply voltage. The 1000/35 has "K" motive on the top of the can. The 680/65 has "8" motive. I was disappointed when I purchased a lot of 680/65 from a friend, and found out that it was not as good as the 1000/35 .

Thank you very much for the information, I will check the `8' motive once I get them. But I read here the F series is old:

Black Gate Audio Capacitors

Regards
Roushon