Re: No Transmit QCX

Alan de G1FXB

James W4JED,

    if it's not too late, before you discover it the hard way...
The kit designer has implemented a gotcha to discourage unauthorised copies of the QCX being built.
Burning a non genuine QRP-Labs supplied ATmega IC will not result in a functioning QCX,
(I believe it's being reported elsewhere it displays something to the effect 'none genuine'?)

You should be OK to reflash the original IC.

You may wish to review the Mods / Trouble shooting pages, to see if yours is a result of incomplete MCU boot / reset
Also separate comment specifically in the Buttons / rotary encoder don't work properly section, highlighting need to check / modify if necessary if yours is a Ver 1/2 PCB.

Looking over the past posts when used before a factory reset, it has being reported to 'fix' some side tone / no alignment signal 'funnies' where the MCU saved data becomes corrupt,
Sometimes it goes beyond repair?
It may fix your keying signal working in one function and not another, may be not?
It won't cost anything to check.


On 02/04/2018 14:41, James Daldry W4JED wrote:
On Sun, 01 Apr 2018 18:15:54 -0700
"Jim Carlson" <tshotshoto@...> wrote:

Hi Jack,

I'd be happy to look at your QCX with the commitment on your part
that no money changes hands!  I'm just happy to help.  I have built
one QCX but it worked the first time so I don't have experience
trouble shooting but I am a retired electronics engineer (from
Motorola) so I have a lot of experience.  I have the proper test
equipment for this task.  Let me know if you would like to send it to
me.  My contact information is correct on

Hi, Jim

For about 10 years at my last job (1988 - 2010) I repaired VCR's and
camcorders almost exclusively - maybe 40 a week. Yes, most of these
were mechanical problems - belts, etc - but a fair number were logic
problems. Most of these, in turn, were things like bad pickup coils,
bad hall effect devices, bad optocouplers, etc, but a significant
fraction were microcontroller problems. VCR's have anywhere from no
micro's (Panasonic NV-8170, with 2 large boards full of CMOS), to 6 or
7, depending on how servo systems were designed. Some micro's had
blown cmos capacitors on input pins (circuit is loaded down by the
input pin, and can be made to work by adding a current amplifier), weak
output "totem poles", etc, but occasionally you would have bad firmware
like a whole family of Matsushita 1985 decks that would burn the front
load assembly motor because there was no timeout on the basket motor
drive. The replacement was MN15846VRG3, which replaced one without the
3. We kept 2 of that one in stock. 

In this case I have a key_out line that is not responding to the
NOT_dit signal, but does respond to the keyer code practice function.
So the output pin is good. When you disable the key_out by pulling the
pin out of the socket, the s-meter goes full-scale on key presses. The
dit pin is functioning. The only thing between them is the micro and
its program. So - I've downloaded the hex file and will be firing up
avrdude to burn it to one of my own '328's. I have a current-limitted
supply so I won't be letting the magic smoke out. Thanks for
volunteering, but I think I have this handled.


Jim Daldry W4JED

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