K4307 dead

Kits Audio Hi Fi Projects
1

I’ve built the K4307 today, but it’s dead! No led’s light, even though I’m putting 3.6v @ 30hz . I also went up to 1khz.

I’ve been over every joint and DC voltages at the led’s, diodes and zeners seem about right.

Anyone had the same problem?

2

Did you try a higher voltage?
Sorry, this forum does not allow picture uploads
If you can provide LINKS (e.g. by using a free online picture base) to HI-RES and SHARP pics of your assembly (both solder- and component side)
then we can take a look and provide some feedback.

3

Hi

I didnt try a higher voltage, it was getting too loud!

DSC_8420 by morticiaskeeper, on Flickr

DSC_8419 by morticiaskeeper, on Flickr

4

As far as we can see on the pictures, some solderings look poor and might need rework.
We cannot judge if the leds are correctly inserted.
If the problem persists after checking the leds and reworking the solder joints and you are sure that the input level is high enough, then we suggest to return kit for inspection/repair.

5

Thanks, I’ll rework any joints that look dodgy. I turned the first LED just to be sure.

I’ll try a higher power with ear plugs!

6

It works!

I haven’t done anything to it, but decided to risk testing it without a speaker. It seems that my DVM doesn’t give a an accurate reading on AC music.

When the amplifier was really driven, it worked. Tested with a bass, it worked properly.

I will now fit it into the back of the speaker cabinet.

Thanks for your help.