Replacement Capacitor for BC-5?

[kjoosten]

Got a BC-5 for my S3 2000, but it appears to be no-op. Thought I'd try a new capacitor - does anyone know of a replacement for this?

 

[Stu W]

Kent, did you try "reforming" the capacitor? Flashes that sit too long will need the caps reformed. Just do a google search and I'm sure you'll find something. Stu

 

[cwereley]

Hey all, I'm in possession of a BC-4 and BC-5 and a load of flash bulbs I got on the cheap. The dang 22.5V battery is the expensive part relatively speaking.


Has anyone had any experience with replacing the capacitor? I have sourced some 25VDC ~200uf that are shorter than the compartment, and have been contemplating how I will mount it. Perhaps build a receptacle the same size as the original capacitor and place the new/modern capacitor within it. Or solder the new capacitor right across the contacts? Concerned heat from soldering may damage other components within the flash housing.


If anyone has done any type of capacitor replacement with some success, Id sure like to hear about it. What worked, what didn't.


The capacitor within my BC-4 has specs on it, 25VDC and 200MFD. Unsure if it is original. The capacitor in the BC-5 just has printing "37.6". The manual doesn't state the capacitor specs, just says to buy a new one from Nikon. Anyone know the proper specs for original capacitor for BC-4 and/or BC-5?


I don't have the BC-7, but see it uses a lower voltage battery, 15V and appears that the capacitor isn't as easily accessible as the earlier models. Does the BC-7 have a replaceable capacitor as well, or is it soldered?


If anyone can share any insight or experience, I'd appreciate it. When I do a capacitor change, I'll post my results/frustrations/experience!

 

[cwereley]

Received my 22.5V battery yesterday as well as some Sylvania and Philips bulbs, and was surprised to find both the BC-4 and BC-5 units work with their original capacitors! Wow those bulbs create a lot of fantastic light and looking forward to creating some stills with these old units and bulbs. Planning on fabricating a new spare capacitor by creating a shell that conforms to the original size with contacts, then placing a smaller capacitor with similar specs inside. Anyone else still doing flash photography and/or fabricated capacitors to fit in these units?


TIA

 

[View Range]

The reason there is a capacitor in the flash is that flash bulbs draw a high current very briefly when fired. The battery in the flash has trouble producing the required current, and its ability to do so decreases as the battery gets older. Being a 22v circuit does reduce the current. I would be surprised that so many capacitors would fail in these flashes so make sure the battery is good first. Just because you bought a "new" battery does not mean it is in fact new. The battery could have been on the shelf a long time.
The current involved in bulb flashes results in that they should not be used in modern cameras. Flash triggers in these cameras are designed for modern electronic flashes and can be damaged by high current.