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Re: Power on issue solved on my QCX :-)

 

Dear all,

I got a power issue, and it is from not L6 but L5.

My problem is "A row of blocks appears on the top row", described at manual 6.3.
With measurement, LCD's D4-D7 is about 1V. I understood CPU didn't work with LCD.
I re-soldered LCD, pin header and atmega328p, but not solved.
Also I read 328p fuse bit with ArduinoISP, so I could read it (and it shows external xtal).

Next, I tested the pins of 328, VCC is 5V but AVCC is only 4V.
I checked a resistance between AVCC and 5V, it is 600ohm.
So, I re-soldered L6, work fine.

It caused by my bad soldering of course, also
I suspect the wires of inductors is coated something.

Now it works well for receiving without C1 is completely open.
?(Best freq is 6750kHz, No problem to use in 40m.)

Regards.

toyo / JG2RZF?

2017Äê10ÔÂ9ÈÕ(ÔÂ) 20:49 DL3HRT <dl3hrt@...>:

My QCX (#241) suffered from the power on issue. After power on it did not start. I had to switch power off and then on again. My first idea was that the display was not reset properly but it turned out that the processor itself did not start.

After a closer look at the schematic I suspected L6 as the problem. I reduced it from 100?H to 47?H and now I do not have problems anymore:-)

I think that supply voltage at VCC did not rise fast enought which caused the reset circuit to stuck.

Regards

Karsten - DL3HRT

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