What does this mean?

CamaroMurph

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OK.. PCB with a socketed 2716. I am checking resistance. I put one lead on the solder side of the board at Pin 1. I put the other lead on the leg of pin 1 of the 2716. I get a resistance of 20+ ohms. Almost 100 ohms on another pin. The rest are 0 ohms. I expected 0 ohms on all. The two with the high resitance are the Vcc and GRD leads. The rest of the 2716's on the board read 0 resistance on the Vcc and GRD leads.

Fire away.

Murph
 
Corrosion on the chip's pin or on the socket. Clean the pins and test again. If still not 0 then replace the socket.
 
OK. I'll pull the chip tomorrow and look to clean the legs. I'd do it tonight but I should wait until the Jameson wears off........

Anything specific to look for on the socket when I pull the chip?

Murph
 
Crusty, dirty, or frosted gunk on the socket...

Pins on the chip should be clean, bright, and shiny.
 
Muahaaaaaaa...................

Checked all the socketed chips and had a few other problems also. Some of them did not look dirty when I took the chips out. So I just put them back in and checked them. They were now good. 0 ohms. Some of the smaller socketed chips were pretty dirty. So I cleaned them and put them back in and they also now look good. While I had the boards apart I put in all new caps.

I now have my grids and twinkling stars back on Radarscope.

Thanks for the help guys.

Murph
 
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