4558 without pin dot & a couple of questions

[suicidalmoose]

Hi, I'm doing my first project right now (orange squeezer) it's not going too well, all the parts are soldered (rather well i thought) but there's no audio coming out of it at all.

I've got 3 questions:

1) the RC4558's i bought do not have an indent or dot marking one of the pins, like is shown in all of the photo's ive seen on these boards, and on the diagram - how do i know where that ground pin is? i swear there is absolutely no marking front back or side to suggest a ground pin, however it does have the general IC text on it (where would the dot be in relation to this). - http://www.banzaieffects.com/RC4558-generic-pr-16779.html. should have i bought a JRC ? what's the difference?

2) How can i tell by looking at the 1n100 diode, where the negative and positve connections are? the legs are about the same length, so is there anyway of telling by looking at it?  - http://www.banzaieffects.com/1N100-pr-16430.html

3) Can i use a regular pot in place of the trimpot, i know this is hypothetically a bad idea but i forgot to order a trimpot and have a regular pot lying around. this wouldn't be causing the problems woudl it? it's rated at the same resistance.

Thanks guys, sorry for being such a newbie, i just have some general inexperience working with some components (back when i did electronics at high school we didn't really delve into Ic's or diodes, or pots).

[darron]

1) if it has absolutely no markings, then without testing it i would say that the marking would go to the left of the text if you were looking at it the correct way i've never seen a chip that wasn't like this? then again, ive never seen one without a notch, or dot.

2) diodes will usually have some sort of identification mark such as a bar that wraps around closer to one side, or one side will be blackened. that side is negative.

EDIT: from the image on the page you sent, the bottom left hand side is negative.

3) regular pot should do the trick. until you can either get your hands on a trim pot or find the value you want and replace it with a regular resistor. i'm not familiar with this circuit though.

[suicidalmoose]

cheers! i guess i can just flip the chip around and try it like that if all else fails. thanks for the info on the pot and the diode! ill have a go tonight!

[Paul Perry (Frostwave)]

"i guess i can just flip the chip around and try it like that if all else fails."

Perhaps not....chips rarely survive reversal.
Darron is right though, as you read the writing on the chip, the bottom left pin is number 1, then they go around the chip anti-clockwise.

[suicidalmoose]

orrite, i'll have a look tonight, I wish i actually had a place to solder, right now i'm soldering on a metal board on my bed in my bedroom about the size of your closet, london is really note the nicest place in the world for accomodation and space.