these cap markings always mess me up

[pbman1953]

Some caps come with a "K" instead of a pf or uf


What are:




This is a yellow mylar 
405K
100 CEC


and


Brown mylar colored
104K


Thanks

[sluckey]

405K = 40 + 5 zeros = 4,000,000pF = 4uF

104K = 10 plus 4 zeros = 100,000pF = .1uF

[pbman1953]

Thanks and need help with something else for my YBA 3-




http://www.0rigami.com/vb/YBA3__cool-schematics.gif





Ed has me going through the schematic because possibly the owner before me changed things away from stock . Please look at R 12 & R 46, both are 100K. Could that be a mistake having an extra 100k in the same line? Plus C34, there's already a C32 for the same value at the same connections.

[sluckey]

Please look at R 12 & R 46, both are 100K. Could that be a mistake having an extra 100k in the same line?

R12 and R46 are both necessary. Neither is extra.

Plus C34, there's already a C32 for the same value at the same connections.

C34 is necessary. It is not at the same connections as C32.

[pbman1953]

Ok, For R12 & R46, yes there are 2 joined on the board. The odd thing is that there was never a C34 installed.

[sluckey]

Ok, For R12 & R46, yes there are 2 joined on the board.

Yes, one end of both resistors connect together, but the other ends of those resistors go to two different places.

The odd thing is that there was never a C34 installed.

Really? It's on the schematic and it's a very important cap. I would expect audible issues without that cap.

[pbman1953]

Honestly not there. The only thing close to that size is C32.

[sluckey]

Honestly not there. The only thing close to that size is C32.

I believe you. There really needs to be one there. Maybe it's just hiding from you. Can you post some pics?

[pbman1953]

I took  a couple pictures-


Picture 1-  Green wire from the c32r42 to r47/r10


Yellow wire leads out to r46/r12


Picture 2-  Yellow wire in from c32r42. no cap.


The cap on the right is c9


I know this board needs some cleaning. Possibly thinking of a re-do.

BTW, Ed had me change the r12 to a 82k.

[sluckey]

There must be a 10µF cap connected to the junction of R12 and R46. It could physically be located at the other end of that yellow wire. Put one in. Just might fix some of the hum problems you were fighting earlier.

What was the logic behind changing R12 from 100K to 82K?

[pbman1953]

What was the logic behind changing R12 from 100K to 82K?
I'd have to check with Ed, but it could be a Marshall or Fender type move.

[pbman1953]

Keep in mind that I was not the original owner and there things done and missing. I'm trying to bring it back to stock as much as possible.



I've noticed another mod that looked odd. Looking at the rear  of the Bass pot, there's a 22k resistor leaving the left outside lug and going to the Bass expanders grounded lug. Ed said to remove that.


Next I see on the Bass expander that the there's a .022uF instead of a .02pf. My question is I have a cap marked- 2002/ 1kv. Is that a.02 pf?

[pbman1953]

I have to back up, that 22k is the resistor needed for the bass boost switch. It was just using the lug ,that was already a ground, as a ground.


I also found a yellow .022 J-  ITW- WC- 200v, possibly a lower power .022uf.

[HotBluePlates]

I also found a yellow .022 J-  ITW- WC- 200v, possibly a lower power .022uf.

I think you're right. 0.022µF 200v cap.

By the way, they "J" and "K" for these two caps likely indicate the tolerance of the cap. You'd like a data sheet from the manufacturer to know for sure, but that would be the typical meaning of those markings on capacitors.