|
So this has me stumped. I just completed another QMX build. During the diagnostic testing, I found neither of the pushbuttons are responding. I am lucky enough to have several working QMX radios to use and compare during troubleshooting. This is what I am finding:
--I ran a comparison continuity test of the pushbuttons of a known good control board against the one with the unresponsive pushbuttons. I cannot find any difference. The buttons on each board show the same continuity in pressed and non-pressed states.
--I placed the known good control board into the radio that had the control board with non-responsive pushbuttons. The known good control board worked perfectly.
--I placed the problem control board into the radio that had the known good control board. The pushbuttons are non-responsive.
What else should I do for troubleshooting?
Thanks,
Wayne KB4DSF
|
Check the header on the control board.
-mike/w1mt
toggle quoted message
Show quoted text
On Mon, Apr 8, 2024 at 11:48?AM Wayne Greene <wayne.greene489@...> wrote:
So this has me stumped. I just completed another QMX build. During the diagnostic testing, I found neither of the pushbuttons are responding. I am lucky enough to have several working QMX radios to use and compare during troubleshooting. This is what I am finding:
--I ran a comparison continuity test of the pushbuttons of a known good control board against the one with the unresponsive pushbuttons. I cannot find any difference. The buttons on each board show the same continuity in pressed and non-pressed states.
--I placed the known good control board into the radio that had the control board with non-responsive pushbuttons. The known good control board worked perfectly.
--I placed the problem control board into the radio that had the known good control board. The pushbuttons are non-responsive.
What else should I do for troubleshooting?
Thanks,
Wayne KB4DSF
|
If you install the header wrong way up on the control board it wont contact the main board.
Guess how I know!
|
Hey MIke, and thanks for the idea. The header seems fine. There are no shorts and all of the pins show end-to-end continuity.
Wayne
|
Hey, Chris. I could see how that can happen, for sure. I have the headers installed correctly. The encoders are working, so I'm taking that to indicate the control board header is installed correctly, anyway.
Wayne
|
Wayne, are the encoder buttons working? If they are also not working you should check for continuity from the ground side of any of the buttons?back to a main board ground point. It's probably a good idea to check continuity to the main board ground from each of the 4 buttons anyway. If it's just the two little push buttons, then you might also check to see if resistors R301 and R302 are present and undamaged. Good luck ... Ron
Hey, Chris. I could see how that can happen, for sure. I have the headers installed correctly. The encoders are working, so I'm taking that to indicate the control board header is installed correctly, anyway.
Wayne
|
Check the values of R301 and R302 to ensure they match the schematic. Do this with the control board disconnected. Pin 6 of the connector through the resistor and switch to ground.
-mike/w1mt
|
Hey, Ron. The encoders are working. I just checked R301 and R302. R301 is reading 3.3k and R302 is reading 6.8k.?
Wayne
On Mon, Apr 8, 2024, 14:00 Ronald Taylor < wa7gil@...> wrote: Wayne, are the encoder buttons working? If they are also not working you should check for continuity from the ground side of any of the buttons?back to a main board ground point. It's probably a good idea to check continuity to the main board ground from each of the 4 buttons anyway. If it's just the two little push buttons, then you might also check to see if resistors R301 and R302 are present and undamaged. Good luck ... Ron
Hey, Chris. I could see how that can happen, for sure. I have the headers installed correctly. The encoders are working, so I'm taking that to indicate the control board header is installed correctly, anyway.
Wayne
|
Weird that the Tune encoder button is working but the two pushbuttons
are not. They use the same divider resistor (R211). I suppose you
could try checking the voltage at pin 6 while powered and pressing
each button. Figuring what each button should create is simply a
voltage divider calculation, or measure it with a known good board and
compare with the bad control board. If you can, measure it on the main
board pin 6 for that connector.
-mike/w1mt
toggle quoted message
Show quoted text
On Mon, Apr 8, 2024 at 2:11?PM Wayne Greene <wayne.greene489@...> wrote:
Hey, Ron. The encoders are working. I just checked R301 and R302. R301 is reading 3.3k and R302 is reading 6.8k.
Wayne
On Mon, Apr 8, 2024, 14:00 Ronald Taylor <wa7gil@...> wrote:
Wayne, are the encoder buttons working? If they are also not working you should check for continuity from the ground side of any of the buttons back to a main board ground point. It's probably a good idea to check continuity to the main board ground from each of the 4 buttons anyway. If it's just the two little push buttons, then you might also check to see if resistors R301 and R302 are present and undamaged. Good luck ... Ron
On Mon, Apr 8, 2024 at 10:52?AM Wayne Greene <wayne.greene489@...> wrote:
Hey, Chris. I could see how that can happen, for sure. I have the headers installed correctly. The encoders are working, so I'm taking that to indicate the control board header is installed correctly, anyway.
Wayne
|
OK. I'll check that and report out when I get back to it tomorrow morning.? Thanks all for the help. This one really has me a bit befuddled.
Wayne
On Mon, Apr 8, 2024 at 2:22?PM mike/w1mt < w1mt.qrp@...> wrote: Weird that the Tune encoder button is working but the two pushbuttons
are not. They use the same divider resistor (R211). I suppose you
could try checking the voltage at pin 6 while powered and pressing
each button. Figuring what each button should create is simply a
voltage divider calculation, or measure it with a known good board and
compare with the bad control board. If you can, measure it on the main
board pin 6 for that connector.
-mike/w1mt
On Mon, Apr 8, 2024 at 2:11?PM Wayne Greene <wayne.greene489@...> wrote:
>
> Hey, Ron. The encoders are working. I just checked R301 and R302. R301 is reading 3.3k and R302 is reading 6.8k.
>
> Wayne
>
> On Mon, Apr 8, 2024, 14:00 Ronald Taylor <wa7gil@...> wrote:
>>
>> Wayne, are the encoder buttons working? If they are also not working you should check for continuity from the ground side of any of the buttons back to a main board ground point. It's probably a good idea to check continuity to the main board ground from each of the 4 buttons anyway. If it's just the two little push buttons, then you might also check to see if resistors R301 and R302 are present and undamaged. Good luck ... Ron
>>
>> On Mon, Apr 8, 2024 at 10:52?AM Wayne Greene <wayne.greene489@...> wrote:
>>>
>>> Hey, Chris. I could see how that can happen, for sure. I have the headers installed correctly. The encoders are working, so I'm taking that to indicate the control board header is installed correctly, anyway.
>>>
>>> Wayne
>
>
|
Hey, all. I just finished checking the header voltages. I have attached a drawing of the pinout for the control board header with the voltages I read. I did not get any voltage diffrences at anytime I pushed either of the push buttons.
ANOTHER PROBLEM: So, I was testing the voltages of a known good radio, when it suddenly shutoff. I must have shorted something. I thought I fried one or both of the power supply boards, but that I found out that is not the problem. Thoughts?
Thanks,
Wayne
|
Oops. I forgot to add the image. Here it is.
|
Happy Wednesday, all. I am continuing my troubleshooting of the pushbuttons. I'm hoping someone has other hints for me to track down.
Thank you all so much!
Wayne
|
One thought (but not an EE here) is to check each lead of the 2 encoders for electrical continuity to the metal case of the encoder. There should be no continuity on any of them when checked with a DMM.?
On my most recent build, my visual inspection of those leads looked good, but I failed that continuity test on a couple of the leads. I found that issue before powering up for the first time, so don't know if that could affect the 2 push buttons or not. Worth checking though since it's a common build gotcha.?
--
73
de Roy - KI0ER
Littleton, Colorado USA
|
Hey, Roy. Thanks for the input. I just ran a continuity test between the encoders and their leads and didn't?find any that were shorted. That's a bummer. I just can't figure out what is going?on.
Wayne
On Wed, Apr 10, 2024 at 8:47?AM Roy - KI0ER < ki0er@...> wrote: One thought (but not an EE here) is to check each lead of the 2 encoders for electrical continuity to the metal case of the encoder. There should be no continuity on any of them when checked with a DMM.?
On my most recent build, my visual inspection of those leads looked good, but I failed that continuity test on a couple of the leads. I found that issue before powering up for the first time, so don't know if that could affect the 2 push buttons or not. Worth checking though since it's a common build gotcha.?
--
73
de Roy - KI0ER
Littleton, Colorado USA
|
Hello Wayne,
all the voltages on your image are ok for no button is pressed. I think all the header contacts are connected well to the main PCB.
If pressing one of the small buttons or the right encoder (here called the three buttons) on one pin the voltage must be lower.
So please have a look on the schematic_rev2.pdf page 3.
JP302 is "your" pin header. Contact 7 is GND. So you have the reference to your picture.
Contact 6 is important for the three buttons. On the main PCB it's connected via 2.2 kOhm to VDD (3.3 V).
If no button is pressed you see 3.3 V at the pin.
If one of the buttons is pressed, pin 6 should be connected via one of the resistors R301, R302 and R303 to GND. This forms a voltage divider and the voltage at pin 6 is lower than 3.3 V. The value depends on the value of the switched resistor. (So the controller knows which button is pressed.)
If no button is working, something is wrong between GND and pin 6. I guess either the connection of all buttons to pin 7 (GND) or the connection of the three resistors to pin 6.
You should find it easy using the DMM. For save operation remove the Controls board PCB from the QMX and check resistance of the two mentioned connections.
Hope this will help.
73, Ludwig
|
RESOLVED!! and I feel like an idiot. Thanks, Ludwig. After continued troubleshooting, I decided to just resolder the pushbutton pins. That fixed it. I must have had a cold solder joint.
I cannot thank you all for your help. Thank you all so much for your patience and advice.
73, Wayne KB4DSF
On Wed, Apr 10, 2024 at 10:16?AM < DH8WN@...> wrote: Hello Wayne,
all the voltages on your image are ok for no button is pressed. I think all the header contacts are connected well to the main PCB.
If pressing one of the small buttons or the right encoder (here called the three buttons) on one pin the voltage must be lower.
So please have a look on the schematic_rev2.pdf page 3.
JP302 is "your" pin header. Contact 7 is GND. So you have the reference to your picture.
Contact 6 is important for the three buttons. On the main PCB it's connected via 2.2 kOhm to VDD (3.3 V).
If no button is pressed you see 3.3 V at the pin.
If one of the buttons is pressed, pin 6 should be connected via one of the resistors R301, R302 and R303 to GND. This forms a voltage divider and the voltage at pin 6 is lower than 3.3 V. The value depends on the value of the switched resistor. (So the controller knows which button is pressed.)
If no button is working, something is wrong between GND and pin 6. I guess either the connection of all buttons to pin 7 (GND) or the connection of the three resistors to pin 6.
You should find it easy using the DMM. For save operation remove the Controls board PCB from the QMX and check resistance of the two mentioned connections.
Hope this will help.
73, Ludwig
|
toggle quoted message
Show quoted text
On Wed, Apr 10, 2024 at 11:41 AM, Wayne Greene <wayne.greene489@...> wrote: RESOLVED!! and I feel like an idiot. Thanks, Ludwig. After continued troubleshooting, I decided to just resolder the pushbutton pins. That fixed it. I must have had a cold solder joint.
I cannot thank you all for your help. Thank you all so much for your patience and advice.
73, Wayne KB4DSF On Wed, Apr 10, 2024 at 10:16?AM < DH8WN@...> wrote: Hello Wayne,
all the voltages on your image are ok for no button is pressed. I think all the header contacts are connected well to the main PCB.
If pressing one of the small buttons or the right encoder (here called the three buttons) on one pin the voltage must be lower.
So please have a look on the schematic_rev2.pdf page 3.
JP302 is "your" pin header. Contact 7 is GND. So you have the reference to your picture.
Contact 6 is important for the three buttons. On the main PCB it's connected via 2.2 kOhm to VDD (3.3 V).
If no button is pressed you see 3.3 V at the pin.
If one of the buttons is pressed, pin 6 should be connected via one of the resistors R301, R302 and R303 to GND. This forms a voltage divider and the voltage at pin 6 is lower than 3.3 V. The value depends on the value of the switched resistor. (So the controller knows which button is pressed.)
If no button is working, something is wrong between GND and pin 6. I guess either the connection of all buttons to pin 7 (GND) or the connection of the three resistors to pin 6.
You should find it easy using the DMM. For save operation remove the Controls board PCB from the QMX and check resistance of the two mentioned connections.
Hope this will help.
73, Ludwig
-- Wayne Greene
|
On Wed, Apr 10, 2024 at 05:41 PM, Wayne Greene wrote:
I cannot thank you all ... Thank you all ...
I'm confused ;-) Congrats!
|
On Tue, Apr 9, 2024 at 04:57 PM, Wayne Greene wrote:
ANOTHER PROBLEM: So, I was testing the voltages of a known good radio, when it suddenly shutoff.
Hello Wayne, maybe you made a connection from header pin 7 to pin 5 (the neighbor). Its like pressing the left encoder (Shut down). 73, Ludwig
|
Ronald Taylor