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CW key sticking with Nextion LCD

Joe Puma
 

I recently installed the 5” Nextion on uBitx Rig. I noticed that on the 10 meter band the CW key sticks when pressed and there is a noisy tone that goes along worn it. I guess this is RF getting in the line. If I disconnect LCD from power it goes away. I’ve been trying out .1 uf caps on things I seem to be having RAF issues with and it’s been fixing it with great success. So for the keyer I put a cap over the blue wire going to LCD and ground. It stopped the sticky CW key and I don’t hear the squealing RF in the signal.

Now on 18mhz when I key the CW keyer I hear some hiss when I unkey during that delay time which is 600ms. I also see other weird things that happens during that 600ms delay. When RF was getting in even though it didn’t make the key stick during that delay time, my power and swr goes up briefly. I can make the delay be 0 and be done with it. I only use the CW keyer to trigger my auto tuner so I don’t need the delay but that odd surge in power and swr makes my auto tuner retune after I let go of the CW keyer. It makes using it a tuner tigger useless.

Normally during that delay you dont see any signal but if there is RF in the chain it seems to discharge it back out onto the antenna port during that delay process. This causes the auto tuner to tune.

I’ve only noticed it with the 5” LCD installed.

Jow
KD2NFC

Sam Tedesco
 

Hi Joe,

There was a blocking diode fix on r52 that fixed all of my cw issues. I'm going off of memory...but, I lifted r52, on side towards 2822 chip, add diode in series...cathode down to board. I run my delay 450-500

Joe Puma
 

Which bitx are you using. I have uBitx and R52 is near audio predriver and its a 2n3904. How do I do this on a uBitx v3. I guess this is what we call a carrier burst?

 

Joe

KD2NFC

 



On Apr 9, 2019, at 12:34 PM, Sam Tedesco <stedesco619@...> wrote:

 

Hi Joe,

There was a blocking diode fix on r52 that fixed all of my cw issues. I'm going off of memory...but, I lifted r52, on side towards 2822 chip, add diode in series...cathode down to board. I run my delay 450-500

 

Sam Tedesco
 

I'm on v3, also. I tried looking for the original post, but couldn't find it. Anyway, your descriptions sounds about right. I thought it was odd back when I tried it for the first time...I have a few ver 3 boards and have used it on every one. I'll keep looking for the original info.

Sam Tedesco
 

Joe Puma
 

Thanks Sam!

 

Sent from Mail for Windows 10

 


From: BITX20@groups.io <BITX20@groups.io> on behalf of Sam Tedesco <stedesco619@...>
Sent: Wednesday, April 10, 2019 9:25:17 AM
To: BITX20@groups.io
Subject: Re: [BITX20] CW key sticking with Nextion LCD
 

_Dave_ AD0B
 

I didn't follow the link but You might try a torrid on the orange line and/or between the raduino and nextion.

Joe Puma
 

At first I wrapped a barrel chock on the wires of Nextion. It helped a little. The I put a .01uf on the blue wire of Nextion and ground and that stopped the key from sticking.

Joe

On Apr 10, 2019, at 12:46 PM, d balfour <davesters@...> wrote:

I didn't follow the link but You might try a torrid on the orange line and/or between the raduino and nextion.