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Projects => Tech Help - Projects Page => Topic started by: jimilee on June 06, 2013, 03:44:03 AM

Title: Zero Point SPDX Voltage help FIXED!!!!!
Post by: jimilee on June 06, 2013, 03:44:03 AM
I've built up the Zero Point SPDX and I need help please!!! I am only getting one faint distorted repeat. After taking voltage readings, and looking at other threads, My voltages look good EXCEPT I have zero voltage on IC2 at all,none nada. Swapped out the IC, what would cause that,and where should I start?
Title: Re: Zero Point SPDX Voltage help
Post by: midwayfair on June 06, 2013, 12:57:44 PM
Check for continuity with the power supply and all other +5v parts. Reflow solder. There's a LOT of pads; it's easy to miss something.
Title: Re: Zero Point SPDX Voltage help
Post by: jimilee on June 06, 2013, 02:22:28 PM
I've re flowed everything and still no voltage on IC2, I have continuity on my power supply, i get normal voltage readings on the other ics and the flashy led works like it's supposed to. Could there be a bad part?
Title: Re: Zero Point SPDX Voltage help
Post by: midwayfair on June 06, 2013, 02:28:12 PM
Quote from: jimilee on June 06, 2013, 02:22:28 PMI have continuity on my power supply

TO your power supply -- as in, does the spot for pin 1 actually connect to 5v? Without the chip in the slot? If it doesn't, figure out why.
Title: Re: Re: Re: Zero Point SPDX Voltage help
Post by: jimilee on June 06, 2013, 03:37:15 PM
Quote from: midwayfair on June 06, 2013, 02:28:12 PM
Quote from: jimilee on June 06, 2013, 02:22:28 PMI have continuity on my power supply

TO your power supply -- as in, does the spot for pin 1 actually connect to 5v? Without the chip in the slot? If it doesn't, figure out why.
oooooohhhhh sorry.nope, nothing on Pin 1 at all. Where does its power come from, I'll trace it backwards
Title: Re: Re: Re: Zero Point SPDX Voltage help
Post by: midwayfair on June 06, 2013, 03:42:02 PM
Quote from: jimilee on June 06, 2013, 03:37:15 PM
Quote from: midwayfair on June 06, 2013, 02:28:12 PM
Quote from: jimilee on June 06, 2013, 02:22:28 PMI have continuity on my power supply

TO your power supply -- as in, does the spot for pin 1 actually connect to 5v? Without the chip in the slot? If it doesn't, figure out why.
oooooohhhhh sorry.nope, nothing on Pin 1 at all. Where does its power come from, I'll trace it backwards

From the 5V regulator. Check the schematic. ;)
Title: Re: Zero Point SPDX Voltage help
Post by: RobA on June 06, 2013, 04:14:24 PM
Check the orientation of your voltage regulator. Different brands/models/versions are reversed from each other. Although, that should show up the same problem on the other chip too. Still, worth verifying.
Title: Re: Zero Point SPDX Voltage help
Post by: jimilee on June 06, 2013, 04:18:37 PM
Cool thanks. It's oriented correctly according to the BOM, as a matter of fact I repalced it also. Should the voltage on the transistors be the same? Cause on mine,the Q1 reads 0 0.5 0
update read voltage on the solder side of the board at  pin 1 I have 4.9 on the top side still reads zero, could this be a bad socket?
Title: Re: Zero Point SPDX Voltage help
Post by: RobA on June 06, 2013, 04:43:04 PM
Sounds like it could be a problem with the socket. You could check the continuity between the bottom side of the PCB and the pin on the IC above the socket.
Title: Re: Re: Re: Zero Point SPDX Voltage help
Post by: jimilee on June 06, 2013, 05:07:16 PM
Quote from: RobA on June 06, 2013, 04:43:04 PM
Sounds like it could be a problem with the socket. You could check the continuity between the bottom side of the PCB and the pin on the IC above the socket.
Yep, none in that Pim. Lets see where this goes.
Title: Re: Zero Point SPDX Voltage help
Post by: jimilee on June 06, 2013, 06:01:09 PM
Eureeka! The pin on the socket had gotten bent and wasn't making contact, FIXED IT!!!! Wahoo
Title: Re: Zero Point SPDX Voltage help FIXED!!!!!
Post by: gtr2 on June 06, 2013, 06:45:34 PM
The 'ol socket problem strikes again.  I rarely use them anymore unless I need to try another IC or its a prototype that I'll salvage for parts.
Title: Re: Re: Zero Point SPDX Voltage help FIXED!!!!!
Post by: jimilee on June 06, 2013, 06:55:07 PM
I've never experienced a pin bending in on itself before and I can't believe I didn't notice it. People seem to really love sockets or really hate them. I can see both sides now. Although I would've trashed an ic pulling it out instead of a socket, but I soldered the ic straight in this time because apparently I'm out of 16 Pin sockets now
Title: Re: Zero Point SPDX Voltage help FIXED!!!!!
Post by: midwayfair on June 06, 2013, 07:08:00 PM
That's why I like the "good" sockets with the individual pins. If one doesn't make it into the hole, it's sticking up on the other side. They don't accidentally bend, and the chip legs are always secure. Well worth the extra few cents.

I tried going socketless for a while. I just burned one too many ICs to keep trying.
Title: Re: Re: Re: Zero Point SPDX Voltage help FIXED!!!!!
Post by: jimilee on June 06, 2013, 07:22:45 PM
Quote from: midwayfair on June 06, 2013, 07:08:00 PM
That's why I like the "good" sockets with the individual pins. If one doesn't make it into the hole, it's sticking up on the other side. They don't accidentally bend, and the chip legs are always secure. Well worth the extra few cents.

I tried going socketless for a while. I just burned one too many ICs to keep trying.
yeah, I don't like the idea of completely Socketless either. Definitely worth the extra in that case. I will do that on my next order.
Cool sounding delay what little bit I played it, sounds clean