K4100 Preamp Kit Error

Kits Audio Hi Fi Projects
1

Hi,
I assembled K4100 Preamplifier kit the other day, and that was quite straight-forward process.
But when I plugged in, all the LEDs light (“MUTE” LED flash) and it doesn’t work :cry:

I couldn’t find the reason (I’m newbie about electricity…) so, could anyone point out some hint (probably my mistake) or which part is assumably wrong?

Assumable reason (different from the ordinary) is below (sorry again I’m newbie…)
/I use 120V of the transformer, not 220V.
In addition to this, there is only 100V(Japanese voltage) and the voltage at 9V,12V is
a little under.
/I didn’t fit BUZ part
/I don’t use headphones, so didn’t connect cords for that

Thanks in advance!

2

Did you connect EQ OUT with EQ IN?

3

Thanks for your reply.
I tried, but same as before.
Just plugged power cord, All the LEDs lit.

4

Are the buttons working? Does anything happen when you press them?
Is the keyboard connected correctly?

5

Thanks again (and sorry for my bad English).
Buttons do not work, LEDs always light (keyboard’s pcb-cable is connected or not) and
nothing happens when I press (of course when connected).
I think keyboard connected correctly,… but maybe something wrong.
Should I check fittings from the beginning?

6

This is very difficult to troubleshoot from a distance.
If you post HI-RES and SHARP pictures of both component and solderside of your assembly, we can take a look and try to spot assembly problems.

7

Thanks, Team.
I thought it maybe a simple mistake easily pointed out.
I got to search wrong soldering and fittings (it is my study).
If I can’t find out, maybe I ask again.
Sorry to trouble you.