Hey guys im a high school student from Australia and i bought a K8023 kit for my end of year project and i have assembled it. I’am using a 12v 1A DC power supply and when connected LD11 and 12 light up and when i close any of the ten channels with the COM those LD’s begin to flicker and the given channel LED lights up which sounds about right. However when i connect my multimeter to any given channels and GND on the receiver board it reads a steady 1.2v (logic voltage?) until i touch any of the switch cables and it drops down to 0.4V which is really weird however when i close the circuit at the transmitter the voltage drops to 0.66v now is this normal or i should i be rechecking my circuit for cold solders or is due to open collector outputs?? as you can tell I’m way out of me league right now!
Any help would be appreciated!!
The outputs are open collectors. Therefore, you cannot check their operation with a voltmeter.
Judging by the info you supply, you kit works fine.
Hey its me again sorry to be a hassle but using the information you supplied to me I assumed the board was working and I went out and bought a couple FRS6-5 relays http://www.ateco.it/pdf/art047_frs6.pdf that operate at 37.5mA at 12V. I hooked them up making sure I used the right terminals however when powering on the board and switching the channels on, the relays do not switch from the normally open position to closed. Which is strange as these relays are rated at a lower power consumption than relays other people have used on this board meaning that ether the relays are broken or burnt out or that my circuit board is broken and I was wondering if there was any measurements or tips that would allow me to correctly asses the circuit board. As from my own trouble shoots it has all led me to believe that the two ULN2003 IC’s are not performing correctly.
Can you link to a diagram or picture of your hook-up?
Are you sure they are 12V relays and not 24V?
Did you test them by applying 12V before you’ve inserted them into your circuit?