I finally killed my Rev 1 QDX!


Ryan Flowers
 

Yep. I killed it good. How? Mind you this is a Rev 1 where the 3.3v regulator is powered by 12 V directly and I never changed that, though I am certain I could have. Also, I ran it at 14 V instead of 12 V. And I ran it 24/7 for almost 4 months straight. 

Yeah, I abused it. The 3.3 V regulator let go this evening. I was out of the shack when it happened but I bet it was quite a pop! The Smell was... well you know. The Smell. Video here:

https://www.youtube.com/watch?v=Ka6afCMR3Wo
--
Ryan Flowers - W7RLF
MiscDotGeek - QRP and More (Website)

QDX News, Tips, Build Series (YouTube)
QCX Mini "Mini Tip" Series (YouTube)
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W7RLF Prototyping Boards


Vojislav [YU4HAK]
 

So sad to hear that :( I saw the yt video, and now I'm scared! Do you have details about that power supply mod that changes from 12 to 5v input for the 3.3v controller? Is it here in the group because I have trouble finding it?


Dave VE3GSO
 

Please find attached a photo showing a 78M05 install in place of the AMS1117.

Dave


On Thu, Feb 24, 2022 at 5:33 PM Vojislav [YU4HAK] <batica@...> wrote:
So sad to hear that :( I saw the yt video, and now I'm scared! Do you have details about that power supply mod that changes from 12 to 5v input for the 3.3v controller? Is it here in the group because I have trouble finding it?


Ryan Flowers
 

Yup, the big detail there is cutting the trace that supplies 12v and powers the 3.3v reg from the 5v. That would be the only mod I'd worry about. @Dave do you mind if I use your photo in a video?

--
Ryan Flowers - W7RLF
MiscDotGeek - QRP and More (Website)

QDX News, Tips, Build Series (YouTube)
QCX Mini "Mini Tip" Series (YouTube)
QCX Mini Troubleshooting and Repair (Website)
W7RLF Prototyping Boards


Vojislav [YU4HAK]
 

Thank you Dave, I will definitely do this.


William Smith
 

So, for the TL:dw crowd, can you condense the 10-minute video down to text?

/*

My QDX Went POOF! And I'm not even upset. Why?

*/

Why?  #UseYourWords 8*)

73, Willie N1JBJ


On Feb 23, 2022, at 2:30 AM, Ryan Flowers <geocrasher@...> wrote:

Yeah, I abused it. The 3.3 V regulator let go this evening. I was out of the shack when it happened but I bet it was quite a pop! The Smell was... well you know. The Smell. Video here:


Andrew Lenton
 

Hi Interesting, this makes the case for running the unit at 9V, as less volt drop on the 5V regulator.

73


Andrew


Dave VE3GSO
 

Sure, go ahead Ryan!

Dave

On Feb 25, 2022, at 07:35, William Smith <w_smith@...> wrote:

So, for the TL:dw crowd, can you condense the 10-minute video down to text?

/*

My QDX Went POOF! And I'm not even upset. Why?

*/

Why?  #UseYourWords 8*)

73, Willie N1JBJ


On Feb 23, 2022, at 2:30 AM, Ryan Flowers <geocrasher@...> wrote:

Yeah, I abused it. The 3.3 V regulator let go this evening. I was out of the shack when it happened but I bet it was quite a pop! The Smell was... well you know. The Smell. Video here:


Ryan Flowers
 

On Fri, Feb 25, 2022 at 04:35 AM, William Smith wrote:
So, for the TL:dw crowd, can you condense the 10-minute video down to text?
 
/*

My QDX Went POOF! And I'm not even upset. Why?

*/
 
Why?  #UseYourWords 8*)
 
73, Willie N1JBJ
 Just be glad it's only 10 minutes. When I get started talking, you never know :D

--
Ryan Flowers - W7RLF
MiscDotGeek - QRP and More (Website)

QDX News, Tips, Build Series (YouTube)
QCX Mini "Mini Tip" Series (YouTube)
QCX Mini Troubleshooting and Repair (Website)
W7RLF Prototyping Boards


ohwenzelph
 

Another photo of the same mod, red arrow points to cut trace. (Used enamel wire that I had placed inside Teflon insulation removed from other wire. Scraped off the enamel at the ends. Grounded both the tab and the middle element of the 78M05.)


Mike AE0IH
 

Dave and Ohwenzelph,

Thank you for the photos of your mods.  

Ryan - sorry about the 1117 failure.  Looking forward to your next video as you resurrect your QDX!  

I'm currently halfway through the build of my Rev1 QDX and I'll be incorporating Dave's substitution of the 1117 with a 78M05.  How difficult is it to scrape away the solder mask for grounding the tab?  What's the best tool for the job - an x-acto knife?  I'm planning on using a dremel with dental burr on the trace but will need to be very careful - it's pretty thin.  Also, any thoughts on best way to remove the 1117-5?  I used Chipquick SMD1 removal alloy to remove the smd inductors.  It worked like a charm!  Thinking about using that on the 1117-5.  Your photos, Ryan's videos, along with Hans' excellent Rev1 manual with schematics and board layout have been very helpful as I plan the next steps.   

Thanks to you all and 73,

Mike - AE0IH


Mike Easterbrook
 

Mike
I successfully used Chip Quick to remove the AMS1117 from my Rev 1 QCX mini. 
I don't recall any need to scrape away anything - think I just used flying leads. If I get a moment I'll open up the mini & take a look/photo.

On Sun, 27 Feb 2022, 11:12 Mike AE0IH, <michael.ramos.exec@...> wrote:
Dave and Ohwenzelph,

Thank you for the photos of your mods.  

Ryan - sorry about the 1117 failure.  Looking forward to your next video as you resurrect your QDX!  

I'm currently halfway through the build of my Rev1 QDX and I'll be incorporating Dave's substitution of the 1117 with a 78M05.  How difficult is it to scrape away the solder mask for grounding the tab?  What's the best tool for the job - an x-acto knife?  I'm planning on using a dremel with dental burr on the trace but will need to be very careful - it's pretty thin.  Also, any thoughts on best way to remove the 1117-5?  I used Chipquick SMD1 removal alloy to remove the smd inductors.  It worked like a charm!  Thinking about using that on the 1117-5.  Your photos, Ryan's videos, along with Hans' excellent Rev1 manual with schematics and board layout have been very helpful as I plan the next steps.   

Thanks to you all and 73,

Mike - AE0IH


Dave VE3GSO
 

Yes, any sharp blade can scrape away the solder resist from a small 78m05 sized area.

Dave

On Feb 26, 2022, at 22:12, Mike AE0IH <michael.ramos.exec@...> wrote:

Dave and Ohwenzelph,

Thank you for the photos of your mods.  

Ryan - sorry about the 1117 failure.  Looking forward to your next video as you resurrect your QDX!  

I'm currently halfway through the build of my Rev1 QDX and I'll be incorporating Dave's substitution of the 1117 with a 78M05.  How difficult is it to scrape away the solder mask for grounding the tab?  What's the best tool for the job - an x-acto knife?  I'm planning on using a dremel with dental burr on the trace but will need to be very careful - it's pretty thin.  Also, any thoughts on best way to remove the 1117-5?  I used Chipquick SMD1 removal alloy to remove the smd inductors.  It worked like a charm!  Thinking about using that on the 1117-5.  Your photos, Ryan's videos, along with Hans' excellent Rev1 manual with schematics and board layout have been very helpful as I plan the next steps.   

Thanks to you all and 73,

Mike - AE0IH


Mike Easterbrook
 

Here's the promised photo of the substitution in the Rev 1 Mini.
Difficult to see exactly what is happening, but no sign of any scraping!
Unfortunately my memory of last year's actions is hazy at best and realistically non-existent.
Hope it may help somehow.

Now to see if I can remember how to get the mini back in it's box!

Mike



On Sun, Feb 27, 2022 at 11:32 AM Mike Easterbrook via groups.io <mike.easterbrook.2012=gmail.com@groups.io> wrote:

Mike
I successfully used Chip Quick to remove the AMS1117 from my Rev 1 QCX mini. 
I don't recall any need to scrape away anything - think I just used flying leads. If I get a moment I'll open up the mini & take a look/photo.

On Sun, 27 Feb 2022, 11:12 Mike AE0IH, <michael.ramos.exec@...> wrote:
Dave and Ohwenzelph,

Thank you for the photos of your mods.  

Ryan - sorry about the 1117 failure.  Looking forward to your next video as you resurrect your QDX!  

I'm currently halfway through the build of my Rev1 QDX and I'll be incorporating Dave's substitution of the 1117 with a 78M05.  How difficult is it to scrape away the solder mask for grounding the tab?  What's the best tool for the job - an x-acto knife?  I'm planning on using a dremel with dental burr on the trace but will need to be very careful - it's pretty thin.  Also, any thoughts on best way to remove the 1117-5?  I used Chipquick SMD1 removal alloy to remove the smd inductors.  It worked like a charm!  Thinking about using that on the 1117-5.  Your photos, Ryan's videos, along with Hans' excellent Rev1 manual with schematics and board layout have been very helpful as I plan the next steps.   

Thanks to you all and 73,

Mike - AE0IH


Mike AE0IH
 

Thanks Mike and Dave for the responses. I’ve got a few 78m05s coming from Mouser and will post here once I do the mod and test it.  


Best regards,
Mike AE0IH