Just finished my 4 pole mission board and did the test recommended. I checked for shorts between points on the ic sockets and found a few. Between the green point on ic 1 and all the red points on the other ic are shorting.
Also seems to be shorts between some of the blue and green points Dont know what i have done wrong. Was extremely careful with the build
Post a highres pic of the Backside, there must be some shorts between the Rails.
here is the front and back. The only thing I havent added is the two resistors for the blinking light LED, sinc I believe they are optional. All the solder points look good to me and I cant see where the shorts would be coming from
it looks good actually, are you sure you’re measuring correctly?
yes Im sure. measuring for continuity between red and green points
You are checking for continuity between the various coloured points, without any ICs inserted? There should be no connection between the red points and blue points or red points and green points. If you are getting that many shorts, I’m wondering if there is a connection somewhere that is common, perhaps near the power supply or at the points that carry signals between the two boards? Also make sure the two regulators are where they are supposed to be, it’s easy to swap them, and make sure your polarized caps are in the right polarity position.
yes I am checking continuity between the various coloured points without an ICs inserted. The regulators are in the right spots. But am definitely getting shorts between the green point on IC1 and all the red points on the other ICs
just did the voltage check and everything is fine there. Is that normal if Im getting all those shorts?
have you tried measuring resistances between the rails instead of just continuity?
by the rails, do you mean, resistance between the red and green points?
I will give it a try, what would be normal readings?
Hi, the soldering looks good by the way. If you have a short you would have 0 ohms (or very near 0).
@arch, I am one of the dumbest people on this forum so please do not be insulted when I ask this but how are you measuring continuity? Are you using a multimeter? If the voltage check is working how can there be shorts? Did you check positive and negative voltages from the coloured points?
@ piscione, I may be dumb but I sure dont know what Im doing. So dont worry I’m not insulted. so… that being said. I am using a multi meter with the sound test for continuity. I hear beeps when I check between the red and green points I mentioned earlier. so I put in the LT1054 and did the voltage check. all the positive and negative reads normal i.e. +5 or -5. that seems very odd to me that the voltage readings are good when i am reading shorts between the same points.
I tried it with a resistance check and the readings are around 10 ohms
@ Dunk, I think I am beginning to understand… I should be using the resistance meter instead of the continuity meter to check for shorts
No, you should be using continuity testing mode (continuity testing = resistance measurement with a beep when resistance is less than a threshold, usually a few ohms - it’s the same process, just a different method of signaling the result!). Have you tried with another meter?
not yet but ill give it a try
are the sounds always the same pitch? it can happen that you hear a short beep when the power caps charge first from your beeper. if you have real shorts there must be a steady beep at the same pitch as if you hold the 2 probes together.
if your voltage readings are ok it’s strange if there are shorts. normally the voltage collapses when there is a short.
also be sure to have the Shruthi powered off when measuring continuity or resistance.
yes rosch. the sound is a continues beep. there is no power when I am checking for shorts. I will try what pichenettes suggested when I get a chance to borrow a different meter. Perhaps its just my cheap multimeter