High end control amp k8021 kit version

hello ive assembled and tested the above kit and it works correctly apart from the +6db led is constantly lit even in standby mode and pressing any input button the second time has no effect at all on the +6db led. ive checked the circuit diagram on pages 24 25 and have replaced the led (its inserted the right way around) also r43 r7 r8 and both relays and t7 t8 transistors bc557 type all components are inserted correctly.

ive checked the voltage and its +5v and also continuty checked from +5v to r43 from ld5 to the pic socket on pin 1 then to r7/8 then to t7/8 the bc557’s both recieve +5v also removed the pic but to no avail ive also replaced ry8 and ry7 i also have gnd on pin 1 of sk7 and +5v on pin 2 of sk7 also both diodes on the relays are the correct way

any help would be of assistance thankyou stuart

Remove PIC. Measure continuity between pin 1 and GND.
If this is the case, look for error such as solder bridge, etching error between two tracks etc…

hello vel417 have done what you said and it is the case so i have looked for the etching error between two tracks and there is something there eg a short but cannot find it so here was the remedy

disconnected pin 1 of dil socket from pcb have connected a wire from this to the led5 side of jumper 11 then from here to resistor 7 and also resistor 8 and it works like a dream

i dont think i should really have to correct faults on a kit i have bought with a fault on the manufacturing of the pcb arent these checked after manufacturing as i have spent £140 pounds on this high end kit and numerus hours of fault finding.

id rather not leave the kit with this modification in place due to the manufacturing fault on the board would it be to much to ask for a replacement pcb and axial components then i could rebuild with the larger components stripped from the faulty pcb thankyou stuart

We are sorry for any inconvenience. It is impossible to check each PCB individually. In case of a manufacturing error, you should return your kit for inspection/repair. As a one time courtesy, we can offer a spare PCB, free of charge.

hello vel417 thankyou for your reply so in case of manufacturing error you should return for repair or inspection again at my cost this is the second pcb ive had for this project as the first one had a manufacturing problem on it the solder just rolled off the pads according to the person that sent me this one

so again ive spent £140 pounds on a high end velleman kit and assembled the pcb for possibly a third time and who knows ill have to desolder all of the components to rebuild again with a new supplied pcb

In order to be able to send a spare PCB, please supply an address.
If you do not wish to post your address here, you can send it to support@velleman.be
Careful, this email address will accept your mail only once.