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I can't even communicate with it over usb. Red light not on. Draws only about 60 mA. Using PUTTY com pgm. Checked for 5 and 3v supplies. no problem there. Si5351 putting out 24 MHz or so. TCXO putting out 25 MHz.

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Purchased new, already made. Worked great, then died. Love the little rig. Any ideas?

Thanks,

Jim W7LS

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Forgot to mention that this is a REV 2 pcb.

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Jim W7LS

Jim,? I think we need more details. Is this a QDX or QMX? You can't monitor 5 volt and 3 volt supplies in the serial app on the QDX, and you can only see the TCXO output. Also, what happened leading up to its untimely demise? Is this radio built for 9 volts or 12 volts and how are you powering it? What is your antenna setup??

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73, Dan - W2DLC

I see you mentioned the red light, so it must be the QDX. So how did you check the voltages and frequencies?

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73, Dan - W2DLC

Hi Jim,

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Since this is a prebuilt QDX, I would contact QRP-Labs (Hans) for support. You can not do much without a serial connection.

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Have you tried to load a new firmware?

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From the operating manual:

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Entering bootloader (firmware update) mode:
QDX provides two possible ways to enter firmware update mode:
1) On powering up QDX, you will see the QDX status LED flickers quickly for 5 seconds after
power up, then illuminates solidly. If you power down QDX during this 5 seconds, then apply
power again, QDX will now boot up in QFU (Firmware Update) mode.

2) Select the “Update firmware” menu option in the QDX Terminal (see subsequent section of
this manual). QDX will then enter firmware update mode.
In firmware update mode, the status LED flashes slowly.

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As far as I know, there is no "hardware" way to force a firmware reload.

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73

Evan

AC9TU

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Hi Dan,

This is a QDX. I monitored the voltages with a digital multimeter and an oscilloscope. The usb interface is totally dead.

Tnx,

Jim

Oh. Forgot. The unit was built for 12v and the load was a 50 ohm dummy load. I did burn out the finals and replaced them once. It was working perfectly for months before it went dark. I was powering it with a 12.0v lab supply.

Jim

Hhi,

I used a Rigol 1104 oscilloscope with a 10x probe to measure frequencies and voltages. Sometimes a DMM.

Jim

Hi,

I never get any red light action at all, now. I also have a slightly modified firmware that Hans cooked up for me. I don't remember just what the difference is, but it was working beautifully. It was a small change. I will look back and see what the difference was. Tnx,

Jim

I can't find the firmware tweak, but it was nothing major; just a command change or something. I am still getting no communication via USB. The chips all? have their power supplied properly. It's almost like the processor died. Seems unlikely.

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Jim

Hi Jim,

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Maybe the led is bad. ? Can you try powering on the QDX and turning it off before 5 seconds elapsed? ?Then turn it on and try connecting to your computer.?

73

Evan

AC9TU

Hi,

Tried that. It's dead as a door nail. no computer interface action, no red light, and only 60 mA draw at 10.5V. Using Win 10.

Dunno... Tnx, tho.

Jim