TP2 at 7V

[Qiaozhi]

OK! Sorry if I got you all confused, I am getting 7V on TP2 When I measure with TP10, on 79L05 which is located on U1 I get 12V on the input and 7V on the common using middle pin as gound, Measuring 78L05 which is located on U3 i'm getting 7V output and 9V on the input using middle pin as ground . I am using a multimeter and not the oscop for these readings.

Let's take these one at a time:
Firstly, If you're getting +7V on TP2 with reference to TP10, then U3 (78L05) is kaput. Either that, or there's a short somewhere that's putting 7V onto the 5V line. You can easily check that (as mentioned before) by snipping off the output pin on U3.
Secondly, I think you're getting confused about U1 (79L05) because the pinout is different between U1 and U3. On U1 the middle pin is not the common, it's the input voltage.
Refer to Step 1 in the Build Document, where it says "Measure the voltage at U8 pin 4 (see Fig. 2)" to check the -5V supply.

[Tibuck19]

on 79L05 which is located on U1 I get 12V on the input and 7V on the common using middle pin as gound /// 12 - 7 = 5 GOOD

Measuring 78L05 which is located on U3 i'm getting 7V output and 9V on the input using middle pin as ground/// 9 - 7 = 2 Toast Your getting 2 Volts to much thru the Regulator. Replace it.

That Solved it , and the depth has increased , Thank you too all of you that I have confused Problem Solved, ON to the next one hahahaha. Thanks Homefire and George.

[Tibuck19]

Let's take these one at a time:
Firstly, If you're getting +7V on TP2 with reference to TP10, then U3 (78L05) is kaput. Either that, or there's a short somewhere that's putting 7V onto the 5V line. You can easily check that (as mentioned before) by snipping off the output pin on U3.
Secondly, I think you're getting confused about U1 (79L05) because the pinout is different between U1 and U3. On U1 the middle pin is not the common, it's the input voltage.
Refer to Step 1 in the Build Document, where it says "Measure the voltage at U8 pin 4 (see Fig. 2)" to check the -5V supply.

Correct ashomefire also pointed out , lucky I had on last spare and it solved the problem ,Thanks again George, Sorry for all the confusion I will better explain on the next MD loll

[homefire]

YEAAA! Next !

[Tibuck19]

YEAAA! Next !

loll beside having the ability of confusing everyone, I think for a newbie I ve done rather well hahaha besides you would get lonely if I didn t have so many questions .

[homefire]

Actually this is a good thing for me. I have two PCB waiting to have something done with them. Your the Teacher! I'm leaning all the Pit Fall and crap that can go wrong. LOL Thank You Sir.