Stacy,
Post a schematic for us.
Reading negative voltages in circuits can be due to wrong ground -ve reference. The meter -ve probe is not at 0V wrt the battery/PS.
Check the voltage between the battery or ps -ve and your board ground. Should be Zero.
Check between various ground points, somewhere you should spot a large difference! That area check for cut ground tracks on the PCB.
73 Raj vu2zap
>Does anyone have experience with this kit, G6LBQ multi-band bitx? Iv finished the build but, had some really strange reading with my DMM, all the way, through the build.
>
>Firstly, I thought it was the battery, which seemed very low so it was changed. Secondly, I started using analogue current and volt meters, which helped me diagnose the problem. Thirdly, I realised that the voltage had become negative on the board, I have checked all the components and this was the same, right the way across the build. Lastly, I have checked the bench power supply that was used and, the polarity is good. Basically, if I reverse the +ive and -ive from the supply to PCB then, I can normally measure the voltage. This was so weird...
>
>Its so strange how the voltage has been completely inverted when routed through the populated PCB. Has anyone come across this before, maybe with a bitx? Any ideas on this problem would be greatly appreciated.
>
>Regards & 73
>m0wsa
>Stacy Williams
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