How to check an IC?


Hi,
I just made some ICs, and want to make sure there are no shorts, etc.
Can somebody guide me through this?
What I did is turned my R-Shack voltmeter to Ohm x1. and connected probes to the RCA barrel on both ends, and then to both central pins- meter showed about 400 Ohms? in both cases.
Does that mean the IC is OK?
I'm completely illiterate, when it comes to DIY, etc.
maril555
My spell checker apparently inserted military when I typed mili as in mili ohms.
If you're on the 1 ohm scale the 400 almost certainly means 400 military ohms, aka .4 ohms.
No worries there if it reads 300 milii ohms with the leads shorted (means your cable is adding only 100 mili = .1 ohms).
You should see low ohm readings from outside ground to outside ground.
You should be OPEN from center pin to outside ground connector.
Actually, the R x 1 scale on a Radio Shack analog multimeter is undoubtedly not a 1 ohm scale. It simply means that the number indicated on the dial scale by the pointer should be multiplied by 1, as opposed to being multiplied by 10 if the R x 10 scale were selected, or by 100 if the R x 100 scale were selected, etc.

There should be a small knob somewhere on the multimeter, labelled as "ohms adjust," or something similar. While touching the two probes together, turn that knob until the meter reads 0 ohms. If you can do that, then make your measurements on the cable. If you can't do that for any setting of the knob, it means that the battery in the meter is weak and should be replaced.

After performing that calibration, so that you have a reading of 0 ohms on the R x 1 scale when the probes are touching each other, as was indicated above the cable should measure either 0 or a tiny fraction of an ohm from center pin to center pin, and from ground sleeve to ground sleeve, and it should measure as an open circuit (infinity ohms) from center pin to ground sleeve.

When checking for shorts (i.e., between the center pin and the ground sleeve), it is generally good practice to use a higher scale than R x 1, for instance, R x 1000, to make sure that you will see the small deflection that may result from a high-resistance path between the two points, that shouldn't be there. When you do that, make sure that your fingers are not touching the metal tips of the probes, or you may see a deflection of the meter due to the resistance of your skin.

Regards,
-- Al
Almarg,
You are the man- it was low battery, after changing it and adjusting "ohm adjust" knob, I got the following:
IC #1: appr. 0.5-1 ohm b/w ground- ground and the same b/w center pins.
Infinity b/w ground and pin.
IC #2: 0.5-1 ohm b/w grounds, but 3-4 ohm b/w center pins
Infinity b/w ground and pin.
Does it look, like there is a problem with IC #2?