Debugging tronic's AMC board

I have finished putting on all the parts to tronics AMC board....
went to plug it in and got no LED lights at all.

I think i did a good job on the pcb and solidering.. although obviously there is a short or loose wire somewhere...

I have tested that i am getting 9volts from where the power supply plugs in..

can anyone give me hints/tips on how to debug further?

im going to go over all the soildered points tonight. but if there is any tips on how i can try and find the problem ?

:

Hi,


Some clear photos of the top and the bottom of your board would be great, to see if there is something wrong with the parts used...

Regards, Thanos

Here is my board. I am going to go over all the solidered points slowly and carefully.

I know its not the best job:

Any assisantce would be great! The LEDS dont light up at all.
if you can give me some advice hwo to test it with the multi-meter to find out which point or track is the problem that'd be great!

ps- to admins. my old login wouldnt give my authoirty to view any pages on the forum.

Measure the output pin of the LM2940 to see if it does output 5v. If not, it is faulty and needs replacement.

Also as the LM2940-5 is a LDO parts, the perfect match power supply for it is a 6V ~1A transformer. Be sure that the transformer you used does not have center pole reverse voltage direction switch !!!!

Regards, Thanos

thanks alot!
I'll have a look at that tonight

anything else you can comment about my the board itself?

Well, the placement of the parts looks ok, but the bottom of the board looks like its you etched the lines by yourself... Take a good magnifier and a good source of light and start searching for small short-circuit bridges...!!


Regards, Thanos

The National Semiconductor Specs state Input voltage of 6.25 - 26 volts.

Regards Senetor.

Thas correct, but above 6.25v it wastes energy in the form of heat !!!! Heat makes the VCC output unstable and it will provide less amps than may required by the AMC load (for example to power the LCD backlight ...!)


Thanos

is this what I would use a multimedia and the Continuatlity feature on it for?

test it on each track ect to make sure there is not a short?

not yet. I am working on it with a friend at his place, so i can only do it weekends.. im goign to take all this infomraiton and put it to use on saturday.. (this is why its taken me a couple of weekends to get it together)

I just thought that the continuatily (probably spelling it wrong) feature on the multimeter sends a signal thru the tracks and beeps if it shorts.. so i was wondering if this is what is used to test for shorts?

However i will definetly do everythng suggested, i was just trying to get a list of things to test for the weekend when i try.

Hi Stowaway ( hell of a name ) went down the same road as you and have to say Tronics stuff is great and the Board does work brilliantly , as with most of us novices it will boil down to a very silly issue .. in My case it turned out to be several dry joints , a few solder bridges and even left out wire links , was pulling my hair out at one time because i knew it should work and that i must have done something wrong and guess what i did LOL:-0 the biggest smile i had for a long time was when i found each mistake and got further towards a working interface and then wow wow wow as teh Avdert Goes it does what it say on the tin to see his stuff in action madde by your own hands is brill ... so my advice get a decent magnifiying glass and check check and recheck the components placed correctly , tracks for shorts or dry joints , ID the 5Volt Rail , Jumpesr , Links and Even the crimped connectors because they are the silly things thet tripped a lot of us up ... the PCB works so its just Finger trouble as i call it .. Have fun , it will be well worth the learing curve in the end .. :