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Still getting nowhere fast with my QMX.? Can someone explain what they see when loading software I have 2 files EEPROM? 137kb and 1_00_009.qmx 529kb is this correct or are they not fully loaded?

How does the power off circuit function? My radio turns on ok so switch goes to ground ok, (I have removed controls and shorted the pin to ground to eliminate them also.)

All of my voltages are correct as per K6JTH excellent diagram. Including PWM_5v and PWM_3.3v both show 3.3v p to p voltage @116k.

PWR_HLD battery voltage when power connected.

PWR_HLD 0v when on/off pressed but battery voltage when button released

(I replaced both SMPS boards just in case I missed something)

?

I turn my radio on PC sees the QMX, I load the software (on top of what is already showing in windows file manager)

The current drops from 160ma to 90ma and the LCD turns on at the splash screen showing software version QMX etc and then stays there. Holding on/off button down does nothing. I have to turn power off.

If I turn on now 160ma current I press on and current drops but nothing is displayed on the screen and it will not turn off.

?

What normally happens at the splash screen if no buttons are pressed does it stay there until you press something?

Can anyone guide me on fault finding the power down part of the circuit. I would appreciate any help or suggestions.

Mike

Mike,
read this topic, it might help you:

QMX won't power off and odd voltages on Q103

Just a suggestion.
I'm assuming you know this:
--
Gyula HA3HZ

Hi Gyula
I cant see the pinout drawing from your link but i think it is the one i refer to above. All the voltages show correct there.
My problem is a little different My software loads and the splash screen displays clearly, i dont have any shorts the current when lcd is visible is about 80ma
Thanks Mike

Mike,
when I read the forum discussions, I read the entire topic at 'QRP Labs/Topics'.
I wrote to you in the previous message to read this, because I think it might help.
I quote ( #109038): 'The output of D103 should be "approximately" 3.3V (that's not a minus sign) and 2.426V is way on the low side. Grounding the LIN_REG_EN pin and turning the 78M33 OFF is good. Does it stay OFF when you remove the grounding? That would indicate control had been handed to the processor and it enabled the 3.3V SMPS.'

Because I read in another message: if the CPU has not taken over control, it cannot be turned off as described.
I searched, but now I can't find where I read this.
However, I put the SMPS solutions in a folder.
I note that I don't have a QMX yet, I'm still thinking about it.
I'm interested in technical solutions, so I'm keeping an eye on them.
I hope you manage to solve the problem.
--
Gyula HA3HZ

Hi Gyula
Sorry if my response seemed negative, i appreciate any help that is offered.
I think the QMX was released to soon for someone at my level of expertise. Lot of people having problems dozens buying power supply boards, even someone with a prebuilt unit had a problem.

The output of D103 is 3.8v and if i groung LIN_REG_EN in turns this voltage to zero and it stays there untill i press the on/off when it comes back on.
Mike

On Sun, Sep 24, 2023 at 12:27 PM, Michael Warrington wrote:

PWR_HLD battery voltage when power connected.

PWR_HLD 0v when on/off pressed but battery voltage when button released

This is not good. You've got a short somewhere causing this. This has also probably damaged the port on the MCU. Once you fix the short you'll still have an issue with PWR_HLD.

-mike/w1mt

You write that
"The output of D103 is 3.8v and if I groung LIN_REG_EN in turns this voltage to zero and it stays
there until I press the on/off when it comes back on."
The output of D103 is Vdd, which could be a maximum of 3.6V if the D109 Zener regulates it.
By the way, the power supply voltage of the CPU, which can be between 1.7...3.6V according to the data sheet.
So the error is somewhere here. The question is whether the CPU did not receive a higher voltage,
which it did not survive, than the maximum according to the data sheet.
--
Gyula HA3HZ

Hi Mike
PWR_HLD when battery connected is? zero
PWR_HLD when on/off is pressed is 3v and says at 3v pressed or not.
Mike

3v is better than battery voltage.

-mike/w1mt

Hi Gyula
I measured VDD 2.99v when powered on.
Mike

OK I have read enough about the QMX, im putting mine in a box labelled " I should have Known better".Maybe when some information on fault finding becomes available I will give it another go.
SMPS boards are selling like hot cakes, everone is convinced they are doing something wrong.
I built 3 qcx minis and the 50 watt amp and have been pleased with them. My smps was damaged unpluging the power supply from the radio.
Good luck everyone.
Mike