Bc 107b philips

[Markus Kersius]

just found a little NOS treasure with a bunch of philips bc107b's and mustard/tropical fish caps/radial Electrolytes.
Need some inspiration and suggestions for something to build with them.

 

[ManicStrat2112]

Nice! Colorsound one knob fuzz or the Colorsound overdrive are cool with bc107b. Also the DAM Meathead and silicon fuzz face are a good choice......oh and WEM pepbox….that's it off the top of my head.

 

[Chuck D. Bones]

Cool! You'll want to test those electrolytics for leakage before using them. They have a finite storage life.

 

[Markus Kersius]

Cool! You'll want to test those electrolytics for leakage before using them. They have a finite storage life.

I did!
2 of the 100uf read way over 200uf! ?
The 10uf were fine though, even as the tropical fish caps, these were pretty consistent in their values.
Also a few polystyrene 1nf in the bag, they measured: ... well.. 1nf precise!
I'm really impressed by these old philips stuff, and thats not only because i'm a Dutchy ?

 

[Chuck D. Bones]

I was suggesting that you measure the leakage current at something near their rated voltage. Be sure you discharge them afterwards.

It's a bit strange that a 100uF cap would read more than 100% above the nominal value.

 

[Markus Kersius]

I was suggesting that you measure the leakage current at something near their rated voltage. Be sure you discharge them afterwards.

It's a bit strange that a 100uF cap would read more than 100% above the nominal value.

I only measured capacitance which read well over 200uf, which is quite a drift.
They are rated 63v.

 

[Chuck D. Bones]

What's the highest DC voltage you have available? 9V or 18V are better than nothing. Put a 10K resistor in series with the cap and charge it to 9V or 18V. Measure the voltage across the resistor to get the leakage current. Might take a few minutes to stabilize. 1V = 100uA, 100mV = 10uA, 10mV = 1uA. If it's under 10uA it's good. If it's over 10uA it's suspect and if it's unstable or over 50uA, the cap is bad. When you're done, disconnect the power and discharge the cap with the 10K resistor. Never discharge electrolytics with just a jumper wire, you need something to limit the current or you can damage the cap. Yeah, the loud POP is exciting and all, but sometimes it's too exciting.

 

[Markus Kersius]

Thnx! I got a 24v supply max, how fast will it discharge with the 10k?