On the scrounge….

Phil hodson

Phil hodson

Well-known member
Evening all!

I’m on the scrounge for a 470UF electrolytic capacitor rated above 35v.
Does anyone have one I can beg, borrow, buy!? Or know of where I can get one that isn’t the size of a house! I need one to finish a build I’m working on.

Thanks in advance.

Phil
 
Depending on what it's doing in the circuit you could substitute a smaller value no problem. Do you have a schematic?
 
It’s for a Total Recall. It’s the only one that needs to be 35v or more so I’m guessing that’s quite important.
Many thanks @MichaelW. DM on the way! I must have missed those on my last order 🤦‍♂️
 
That 470 cap is in the power section. There’s also a 100nf cap in parallel for DC filtering. You would be ok with a 220 or possibly even a 100uf cap there. Just saying.
 
Really. That’s very interesting. Much appreciated. @MichaelW has helped me out. So by the time I have drilled my enclosure I’m sure they will be here.
I thought as it was specifically rated as that it was important. I do have some 220 and 100 at 50v so could use them in an emergency.
 
@BuddytheReow
I have been looking at the schematic and understand what you mean about it being in the power section. That’s why I assumed it needed to be a high voltage rated one.
So what does the big value electrolytic and and film cap in parallel actually do.
And why could the electrolytic be dropped to 100uf with out being an issue. I assume they would still need to be 35v+ rated?
Would a tantalum one be ok in there?
Sorry for all the questions.
 
Phil hodson said:
Really. That’s very interesting. Much appreciated. @MichaelW has helped me out. So by the time I have drilled my enclosure I’m sure they will be here.
I thought as it was specifically rated as that it was important. I do have some 220 and 100 at 50v so could use them in an emergency.
Click to expand...
@MichaelW fell through....he's a bum.....he didn't have one rated for 35v. Only 16v and 25v.
 
Phil hodson said:
@BuddytheReow
I have been looking at the schematic and understand what you mean about it being in the power section. That’s why I assumed it needed to be a high voltage rated one.
So what does the big value electrolytic and and film cap in parallel actually do.
And why could the electrolytic be dropped to 100uf with out being an issue. I assume they would still need to be 35v+ rated?
Would a tantalum one be ok in there?
Sorry for all the questions.
Click to expand...
I just took a look at the schematic and it's interesting that he chose 470u + 100n parallel for power filtering. (Essentially making it 470.1u total capacitance)
And this is before the voltage regulator. I'm assuming the 35v rating is because you have 24v coming in from the wall wart. I agree with @BuddytheReow . If you had a 220u rated at 35v (I DO have some 220u's @35v but they're pretty massive) or 100u @35v (pretty common) I'd put one of those in there and maybe bump up the 100n to a 470n. I really don't see it impacting how the pedal will work or sound.
 
@Phil hodson one more thought. I took a look at the board layout and there's pretty generous clearance for C42. You could fit an oil drum in there.
Look at the last page of the build doc's with the picture of his build and C42 relative to IC next to it. It's massive!

Let me know if you want me to send you a 220uf @35v.
 
You are right @MichaelW there is a lot of room but I was worried about height more than anything.
So I have some 470uf rated at 25v and a good height.
I also have some 35v 330uf. A bit tall but I could bend if needs be.
And 25v 220uf
And 35v 120uf
And 35v 100uf.
So take your pick 🤣

I also have some 470n film but have already soldered in C43.

Thoughts and advice welcome…..
 
Phil hodson said:
You are right @MichaelW there is a lot of room but I was worried about height more than anything.
So I have some 470uf rated at 25v and a good height.
I also have some 35v 330uf. A bit tall but I could bend if needs be.
And 25v 220uf
And 35v 120uf
And 35v 100uf.
So take your pick 🤣

I also have some 470n film but have already soldered in C43.

Thoughts and advice welcome…..
Click to expand...
I would use one of the 35v ones. 25v isn't enough margin of error for the incoming 24v.
 
I’m sure the 220 would be fine. When you already have a good DC source, the PS cap is more of a local reservoir than anything else, and the size would be based on expected current draw, so there’s always a good reserve on tap. If you wanted, you could parallel another cap to give you more reserve. I often put bypass or extra caps on a board bottom—I’ll leave the front side cap’s leads a bit longer, and solder onto them.

The smaller “bypass” cap is there to give you better high frequency response time, and upping the 100 nF size doesn’t help in this regard. In the high end audio world, people parallel multiple caps, the big reservoir electrolytic and then several descending in size smaller film caps to do this—several companies began building caps that had this built in even.

When I first started building pedals, I always put in a much larger than spec’ed cap. Then I began to understand that not having a large reservoir was important to the sound of certain pedals. Typically, if you are shooting for a clean sound, the extra reserve doesn’t hurt.
 
Thanks @Alan W and @benny_profane
Your explanations have helped a lot. I’m going to stick with the prescribed cap and get one ordered up. They don’t seem to be a regular item that’s for sure. May get a couple extra incase this comes up again. I have found some I can use on mouser and I’m sure there are other things I forgot/need 🤦‍♂️
 
You must log in or register to reply here.

Similar threads

D
Capacitor selection and exchange
Replies
3
Views
452
DailyDovetails
D
K
Re: Decadence Preamp Elec Caps
Replies
9
Views
445
Robert
Robert
H
Sourcing electrolytic caps for Duocast build
Replies
16
Views
1K
Cybercow
Cybercow
Fizz
Where can I find a .68 uF electrolytic capacitor?
Replies
10
Views
595
Fizz
Fizz
T
Dual Overdrive With One Input And Two Individual Outputs For Two Amps - Is It Possible?
Replies
3
Views
386
jcpst
J
Back
Top