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I'm just starting build 2 having failed first time round.

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I've just got a main board out of the wrapper and measure 916R between VDD and 0V - I was expecting 9-10K.

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Anyone else know what I should expect?

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Mark

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Oops - this is a QMX+ main board ...

Mark, 9K is what most are seeing, but my brother recently measured his brand new QMX+ board out of the bag and found 262R Vdd to ground. He installed the DC input connector?and the two power supply boards and temporarily shorted the PWR ON point to ground and the thumb drive came up on the computer ready to accept firmware. It seems the MCU Vdd short to ground measures 1R or so when it's there. So he continued his build (still in progress). Not sure why it has the lower than normal resistance on Vdd but it isn't the MCU in his case. Seeing 916R you can probably proceed, but you might want to do as he did and verify the MCU is OK before investing all the time in building it... Good luck .. 73 .. .Ron

As Ron said whenever there is a serious VDD to GND short, it’s usually less than an ohm. ?On all the rigs I’ve fixed, it was about .4 ohm. I always build a QMX or QMX+ so that I can test the cpu very early in the process. ?I install the power connector, the 2 SMPS boards and the whole front panel. ?I power it up at 6.1 volts and load firmware. ?

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73
Jeff Moore
W1NC