Circuit problem! Current flowing, but not powering anything...

Thread Starter

TheMatrixAgent22

Joined Jun 15, 2018
4
So, I just started studying with electronics... and I am kinda struggling with this LM317 voltage regulator kit assembly that I became 3 days ago.

I built the circuit correct... I checked the circuit with my test light screwdriver (haven't received my starter kit yet), including the + and - of the electrolytic capacitors... there is voltage... but my LED and my mini multi-meter isn't turning on... also, my potentiometer isn't changing the voltage, and there is no voltage in the output... any tips?
 

bertus

Joined Apr 5, 2008
20,314
Hello,

Can you post the schematic you are using?
Is it also possible to post a photo of your setup?
You can upload the pictures using the "Upload a File" button below the reply box.

Bertus
 

dl324

Joined Mar 30, 2015
9,956
I just started studying with electronics... and I am kinda struggling with this LM317 voltage regulator kit assembly that I became 3 days ago.
Since you're just starting, the main purpose of soldering components is to form a reliable electrical connection; not mechanical.

Wait until you have a soldering iron before tryng to proceed with this project. When you get your soldering iron, find someone who can show you proper technique. Then practice until you can consistently make good joints.

Unsoldering is significantly more difficult than soldering, so be patient. Trying to run before you know how to walk will be an exercise in futility and will only be a source of grief and dissatisfaction.
 

dl324

Joined Mar 30, 2015
9,956
Thank you so much for all the answers!!! This really will help me! I am never leaving this forum.... XD
Time will tell. Many of us will be brutally honest with you...

Do yourself a favor and get a lead bending jig or some needlenose pliers. You want to take pride in your craftsmanship; or at least, not be embarrassed by it.
upload_2018-6-15_7-57-48.png
https://www.jameco.com/z/801-Lead-Forming-Tool-for-Resistors-and-Capacitors_106884.html
$4.95 seems excessive to me. I bought mine when it was more like $2.

There's no reasonable excuse for workmanship like this:
upload_2018-6-15_8-0-2.png
The leads on those diodes should be formed more uniformly. Whatever method you use to bend the leads should ensure that minimal stress is place on the lead where it exits the body. With pliers, you grip the lead where it exits the body and bend the lead.

Even with the lead forming jig, you want to center the component body in the gap, orient any markings so they'll be easier to read when installed, and apply finger pressure on the lead being bent. The bends should be about 90 degrees. I don't care for techniques that encourage you to bend leads to hold the component to the board until it's soldered. That technique will make rework more difficult and it's unsightly.

Here's an example of one of my homemade boards:
upload_2018-6-15_8-8-3.png
Note how the resistor color bands are all oriented in the same direction.

When you're soldering, you'll find it easier to start with the "shortest" components first. Until you become proficient, you should insert and solder components one at a time; using your finger to hold the component flush with the board while you solder. Until you master that technique, starting with the shortest components will allow you to let your work surface do that for you. But using a finger lets you rotate the component so the leads are perpendicular to the backside of the board.

A "third hand" will be helpful, but you'll find that you can use a pinky finger to position the component, and hold the solder between thumb and forefinger of the same hand.
 

dl324

Joined Mar 30, 2015
9,956
Should have mentioned this earlier.

You can use flat/smooth jaw needlenose pliers to straighten the leads and reform. Put the jaws against a bend and squeeze. Do this repeatedly until the leads are straight.

You'll be surprised how straight you can get the leads with this technique. I've used it to straighten leads on thousands of components.

But don't expect to be able to redo 90 degree bends more than a few times. Bending causes metal fatigue. Repeated bending in the same place will cause the lead to break.
 
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