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QMX+

 

Just finished my QMX+ and really enjoyed the build. Built a QDX a couple of years ago and it has been great.

Powered up at 9 volts and no smoke! Draws about 100 ma and audio out can be controlled and tune appears to work and mode / band does something. Connecting an antenna increases the noise so it appears the receiver is working.

But nothing appears on the display except for the backlight. Turned the pot from stop to stop with no results.

I’m going to touch up all 16 of the display header pins. What a bad place for a soon to be 83 year old duffer to be soldering. Why couldn’t that bave been added to the display board before mounting?

Any other thots?

72/73
Jim w0nkn
 

On Mon, Apr 7, 2025 at 08:28 PM, james jones wrote:
I’m going to touch up all 16 of the display header pins. What a bad place for a soon to be 83 year old duffer to be soldering. Why couldn’t that bave been added to the display board before mounting?
It can be, assemble the front PCB, 16 pin connector and display using bolts and nuts between the display and the front PCB.? Solder the 16 pin connector pins to the display only.? This does the inaccessible contacts without the front panel in the way.? Disassemble and reassemble with the front panel, spacers, display, nuts and front PCB.
?
You can also disassemble it when it's all assembled, remove the rear nuts then unscrew the screws, taking care that the various spacers and nuts aren't turning.? Just take your time.? I know because I also missed a soldering one of the pins.
?
Chris.
 

Touched up all display board connections and now I get two lines on the right side of the display. Mostly symbols and 8s and 9s. I can use the rate push to select all 9s hoping to
hear WWV but no joy. I can find some cw signals that sound good but no sure where they are. Some SSB but hard to tune in.

Progress but as still some work to do.

Jim w0nkn

On Apr 7, 2025, at 10:28?PM, james jones <j2@...> wrote:

?Just finished my QMX+ and really enjoyed the build. Built a QDX a couple of years ago and it has been great.

Powered up at 9 volts and no smoke! Draws about 100 ma and audio out can be controlled and tune appears to work and mode / band does something. Connecting an antenna increases the noise so it appears the receiver is working.

But nothing appears on the display except for the backlight. Turned the pot from stop to stop with no results.

I’m going to touch up all 16 of the display header pins. What a bad place for a soon to be 83 year old duffer to be soldering. Why couldn’t that bave been added to the display board before mounting?

Any other thots?

72/73
Jim w0nkn
Sent from my iPhone
 

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Attached is display on my new plus. ?It will
change when I manipulate the encoders but never anything worthwhile. ?

RTFM hasn’t helped much likely because I’m an old timer who shouldn’t be doing this stuff anymore. ?Help would be appreciated!?

Will try for a reset and try to do a hookup to if that’ll reveal anything. ?

Jim w0nkn
image0.jpeg

On Apr 8, 2025, at 9:57?PM, james jones via groups.io <j2@...> wrote:

?Touched up all display board connections and now I get two lines on the right side of the display. ?Mostly symbols and 8s and 9s. ?I can use the rate push to select all 9s hoping to
hear WWV but no joy. ?I can find some cw signals that sound good but no sure where they are. ?Some SSB but hard to tune in. ?

Progress but as still some work to do.

Jim w0nkn
On Apr 7, 2025, at 10:28?PM, james jones <j2@...> wrote:

?Just finished my QMX+ and really enjoyed the build. ?Built a QDX a couple of years ago and it has been great.

Powered up at 9 volts and no smoke! ?Draws about 100 ma and audio out can be controlled and tune appears to work and mode / band does something. ?Connecting an antenna increases the noise so it appears the receiver is working.

But nothing appears on the display except for the backlight. ?Turned the pot from stop to stop with no results. ?

I’m going to touch up all 16 of the display header pins. ?What a bad place for a soon to be 83 year old duffer to be soldering. ?Why couldn’t that bave been added to the display board before mounting?

Any other thots?

72/73
Jim w0nkn
 

Jim,
?It can be done before mounting the display board to the front panel. That's what I did. Doing so requires a little thought and a couple of extra assembly/ disassembly to make sure everything will fit once you go to mount it to the front panel.?
--
73, Dan? NM3A
 

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I’m fairly certain all the pins are soldered on both sides. ?My question is why the display is “corrupted”. ?Processor must be working to some extent. ?

Thanks for the response.

Jim w0nkn

On Apr 10, 2025, at 6:45?AM, Daniel Walter via groups.io <nm3a@...> wrote:

?
Jim,
?It can be done before mounting the display board to the front panel. That's what I did. Doing so requires a little thought and a couple of extra assembly/ disassembly to make sure everything will fit once you go to mount it to the front panel.?
--
73, Dan? NM3A
 

On Wed, Apr 9, 2025 at 04:57 AM, james jones wrote:
Touched up all display board connections and now I get two lines on the right side of the display.
Jim, so something was wrong in this area. Maybe you fixed not all. A missing connection is bad and also some unwanted connection between pins. Such an unwanted connection between neighbour pins may produce what you see.
Please check resistance between neighbour pins starting from LCD pin 3 up to pin 15 (2 - 4, 4 - 5, ..., 14 - 15). The value should be very high. Check the display board alone and connected to the mainboard.
Not only a short but also a higher resistance could bring problems. (And if you will find a problem I guess it's around pin 7 ... pin 14).
?
73 Ludwig
 

On Thu, Apr 10, 2025 at 04:44 PM, @Ludwig_DH8WN wrote:
pin 3 up to pin 15 (2 - 4, 4 - 5, ..., 14 - 15).
Sorry, typo!!!
Correct is 2 - 3, 3 - 4, ..., 14 - 15.
 

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Found two unsoldered pins on the lcd board.?
Now display works great.

Now back to RTFM. ?Planning to start with FT8 before downloading the SSB firmware.?

Ludwig: thanks for your suggestions.

72/73
Jim w0nkn

On Apr 10, 2025, at 9:46?AM, DH8WN via groups.io <DH8WN@...> wrote:

?
On Thu, Apr 10, 2025 at 04:44 PM, @Ludwig_DH8WN wrote:
pin 3 up to pin 15 (2 - 4, 4 - 5, ..., 14 - 15).
Sorry, typo!!!
Correct is 2 - 3, 3 - 4, ..., 14 - 15.
 

Jim, thanks for the information.
Enjoy your QMX+.
?
73 Ludwig

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