Re: Help ! My U3S behaves badly-Punish it!.... #u3s


Are the grounds of the 7805’s tied together well?



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From: [] On Behalf Of PA3CRZ
Sent: Tuesday, July 16, 2019 10:35 AM
Subject: [QRPLabs] Help ! My U3S behaves badly.... #u3s


Hi there,

I decided to redo my U3S casing and wiring, because the last time it was a mess. But it worked !
Powersupply-wise, I now have two 7805's that supply 5V to the oscillator and the U3S respectively.
That's the only big change I made.....

Now, when I start up the U3S I get the splash screen, and then it seems to cycle very quickly through
all available menus, before it ends saying "Press right button".
When I do that, it just starts over cycling through the menus, before stopping and displaying the same message
again, And so on......

Did a factory reset using the button on the PCB, but the behavior stays the same.

Has anyone seen this before ?
Does anyone know what could be the problem ?

FYI, I used Pete's blog for inspiration on the powersupply.
I do not have the oven, so I'm only using two 7805's.

Any help would be enormously appreciated. I'm without WSPR now, and that makes me sad.....

Kind regards and 73,


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