JRC4558N

[Danny G]

RC4558N's (they also say RC412 on them).

These are the only version of the 4558 I can get locally w/o having to order them.  I built a TS-808 awhile back (you guys might remember) and had mucho problems with it, couldn't get it to work.

I just built a Tube Reamer and used these same chips.  You know what, IT didn't work either!  Got out my audio probe and the signal stopped as soon as it hit the chip.  Voltage readings showed the voltage divider was dividing voltage just fine.  

Mebbe it's these particular chips...?  I'm re-building my TS-808, starting over from scratch--now that I've put a project in a box I know I have to build 'em smaller.  I ordered some JRC and RC4558's from Small Bear and those oughta work!

Any ideas about these weird chips I've been using?

[petemoore]

I've never had a bad one I didn't fry myself.
 I suppose ya' never know..but I doubt you were sold bad chips, where did you get them?

[sir_modulus]

did you put them in wrong? :lol:

I remember when I did that to craig anderton's wah/antiwah.....hmm i wonder why it's not working....maybe if i touch the chip I'll  find out. :mrgreen:

My hand didn't heal for a looong time, but anywhoo, ya, I've had faulty chips before(only seemed to happen from the cheaper brands)

[Danny G]

I get them at an electronics wholesaler that I get all my other stuff from.  Great place.  I go to the counter with a pile of resistors and caps + whatnot, the guy looks at it and says "five dollars."  I love that place.

The chip thing is a mystery to me.  I put one in wrong just to make sure I wasn't putting them in the wrong way, and it took a month for my finger to heal.  I even tried a TL072 in the Tube Reamer, and got nuthin.  I already dissassembled the TR to salvage parts, so I can't further test it.  But I'm re-building my TS-808 from scratch and will use Small Bear 4558's.  If those don't work, then I'll KNOW it's me, heh.

Weird.

[lightningfingers]

Well if you used the ROG perf layout for the tube reamer then stuck a 4558/TL072 in it, it won't work because the 4558/TL072 are both dual opamps and the ROG layout states they used a 741 which is a single.

Just a thought......

[David]

My vote's with Lightning.  I used a dual in place of a single once without grounding out the unused inputs.  Smoked the thing AND got a second-degree burn on the fingertip I touched it with, too!  YEOWTCH!  Won't get fooled again!

[Danny G]

A 741... Ok.  No wonder it didn't work!  Heh.  Good thing I didn't burn myself again.  Already took it apart to salvage parts.  

Oh well, got my small bear order yesterday, so my new TS-808 (and BSIABII) should be up and rocking by next week.

[Jay Doyle]

How are you guys hurting yourself by putting the chip in the wrong way? Is there a power supply other than a battery?

Just curious,

Jay Doyle

[David]

How are you guys hurting yourself by putting the chip in the wrong way? Is there a power supply other than a battery?

Just curious,

Jay Doyle

All right, I confess!  I just hooked up one op-amp in a TL082.  Started smelling something burning a few seconds later.  Thought I felt heat from the breadboard area where the 082 was.  Touched it (dummy!   :oops: ).  Yup, it was burning, all right.  Was it ever!  Like I said, I'm REAL careful now about checking which op-amp I have in my hand and which the circuit actually calls for.

[Danny G]

It only takes 5 seconds for those things to heat up, if that.  Holy crap they get hot!  

Don't try it yourself.  Trust us!