MK133 - one light does not stay on

Kits Mini Kits Range
1

Complete novice here!
I have made up the MK133 and all works well except on switch 4. When switch 4 is pressed both LD4 and LD5 light up, but the light goes out as soon as SW4 is released. I have a brand new battery and have double checked diode orientation, also checked that the correct transistors are fitted to the right locations. It could be bad soldering I guess, but I don’t know what is good and what isn’t!

Here are the links to pictures of each side (Hopefully!!)

https://gorx9a-bn1306.files.1drv.com/y3mfG-kUdqEDHBshLkxLpdckhYFnTvp8EtU_4f6M9Q2dWHzv6l8d76IOKA8ofWE6-x6Gp-Ggu0tnYSX4P9UJuvuWlMsEN9Tdr33Ym_2r5–ktfkarmzpyjDJ0l-TvfxUIYvRFbjZ6q5TDSN7-2BhBXx4lpKSuq9eE1I-rxnW9PMhFU?width=800&height=450&t=none

https://hfpylw-bn1306.files.1drv.com/y3mIsR7xObDwUIgYVSUqEVJfHKVSQyOXY6mwNJxtAOtcz_cp3aVX8fH-CNjyVb2yuFOO-Kv56FxOUWfpqgstpgCnt16tLm3Rllint-EBjn3kAFnao7L6ikyr1mGLKnR1-zYvXKE5aHGP7khdaa8jFZOJivftgAhzP_gFIzMY-lg46U?width=800&height=450&cropmode=none

Thanks in advance for any help

2

Hello

Sorry but your links seem to be broken.
Maybe you can upload them to a photo hosting site like www.imgur.com

3

Try these links instead

1drv.ms/i/s!AgVQMYPgtBU2p74rdthjyYsKdhLIDA

1drv.ms/i/s!AgVQMYPgtBU2p74sXrYlEg4fJhx_Gg

Thanks

4

The links work! :slight_smile:

The soldering could use some rework :wink:
Just reheating the solder joints could make the difference.

tools_Header_Joints.jpg?1396777967800×377

Check if the pad is completly coverd with solder.

Best Regards
VEL337

5

Thanks I’ll have a look at it tonight

6

It was a poor solder, it hadn’t stuck to the board, so was attached to the wire of the resistor but not the board! All working now. Thank you