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I received my fully assembled QMX about a week ago, but dont have a mic, or a cw key yet.? I got the high bands since I am a tech so i could use 10m now, and planning on getting my general in june/july.? so all i have done is listen a bit.? I was hoping to try digital modes with it sunday afternoon.? but sunday morning, i turned it on to listen again and about 5 minutes in i change a few bands and then i hear a sharp sound out of my speaker and the radio goes dead.? never to power on again.? double checked the power supply which was good.? even tried a second one and same thing, no power.? i took some multimeter readings while it was unplugged and power doesn't seem to be shorted to ground.? however measuring resistance between antenna and ground is very low resistance, like under 1 ohm.? i haven't opened it up yet as i haven't heard back from Hans.? not sure what next steps would be.

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Thanks for the help / direction.

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Ted

Wow, that's bad luck.

The measurement of the antenna/ground is as expected - it is a DC short, but RF passes fine.

The measurements I would take first are some voltage and current measurements.? The current measurements are particularly instructive:

1) Power supply voltage.? If you can vary the voltage, set it to about 7.5V for the remainder of the measurements.? If you can set a current limit, set it to 250mA.? This will avoid any potential further damage.

2) Power supply current with QMX powered off

3) Power supply current while pressing power-on button

4) Power supply current after releasing power-on button

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Also read the 'startup' page on the Wiki so you know the sequence of events as power is first applied to QMX:? /g/QRPLabs/wiki/36878

All of the above data will help you communicate the details of the problem to Hans, and to you and us if you want to try and fix it yourself.

Stan KC7XE