I just finished up assembly of my DSO 068 and doing Step 2 Power Up Test.
Using the USB for power, the VBUS reads 4.95V, JP2 shorted and JP3,JP4 open.
+5V is good. Power off and closed JP4. Powered up and checked +5V and it is good.
(Now the led on BoB2 is on)? +5V good so I went to the next step.
Pressed SW12 and the Led (D1) didn't light I had closed JP7 and the buzzer didn't
Buzz also. D1 is not reversed and Pin 20 on the U4 reads 4.7V (I don't know if that is low
are not, Can I download a print to help trouble shoot? Capacitor C21 and C22 look
good. I don't know what the Led on Bob2 being on means?
What would you like for me to try next.
Thanks
bigxo
Power Up Test DSO 068
Re: Power Up Test DSO 068
Today I tried using a Battery source and got the same as when I tried the USB for Power?
The Bob2 led didn't light.
The Bob2 led didn't light.
Re: Power Up Test DSO 068
Today I checked U4 and found the following readings.
U4 Pin 64 +5V and Pin 63 Ground.
See a ground on U4 Pin 20 when SW 12 is pushed.
Checked the +5V through Buzzer and through Q1 to R33 to JP7
Also checked +5V to R39 to JP7 Checked with JP7 open and closed?
Checked D1 Polarity and read +5V through R26 to U4 Pin 11.
What should I see on U4 Pins 11 and 16 when powered up and SW12 is pushed?
Is there a way to operate the Buzzer to test it and Test D1 for operation.
Thanks
bigxo
U4 Pin 64 +5V and Pin 63 Ground.
See a ground on U4 Pin 20 when SW 12 is pushed.
Checked the +5V through Buzzer and through Q1 to R33 to JP7
Also checked +5V to R39 to JP7 Checked with JP7 open and closed?
Checked D1 Polarity and read +5V through R26 to U4 Pin 11.
What should I see on U4 Pins 11 and 16 when powered up and SW12 is pushed?
Is there a way to operate the Buzzer to test it and Test D1 for operation.
Thanks
bigxo
Re: Power Up Test DSO 068
The LED on BOB2 was a charge indicator. It lights up when battery is in charging. But if battery is not connected it may also light up at random with no meaning.
For the charger (BOB2) to function correctly battery should always be connected before external power (USB) is connected. Otherwise it may not working. But won't damage anything.
At booting up the bootloader pull U4 pin11 LOW about 400ms to make D1 blink once. The main firmware will pull the same pin LOW twice to make D1 blink twice. While pin 11 is LOW both the bootloader and the main firmware output pulse streams at pin 16 to drive buzzer if JP7 is closed.
For the charger (BOB2) to function correctly battery should always be connected before external power (USB) is connected. Otherwise it may not working. But won't damage anything.
At booting up the bootloader pull U4 pin11 LOW about 400ms to make D1 blink once. The main firmware will pull the same pin LOW twice to make D1 blink twice. While pin 11 is LOW both the bootloader and the main firmware output pulse streams at pin 16 to drive buzzer if JP7 is closed.
Re: Power Up Test DSO 068
Thanks for the Information on Bob2.
Should I remove Bob1,Bob2 and Bob3 until I get the boot loader working,
then reinstall them?
When you say U4 Pin11 goes low for 400ms, do you mean voltage drop?
If so what should it be or should I be looking at output of Pin 11 and 16
with a scope?
I have ordered a new soldering iron and solder sucker to clean off old solder.
I also ordered your DSO 094 to use in troubleshooting my DSO 138 and DSO 068.
When I get the DSO 094 I will try troubleshooting again. If there is something
you wont me to try now that will help you, I'm ready.
I am enjoying working on your equipment and look at it like a challenge.
bigxo
Should I remove Bob1,Bob2 and Bob3 until I get the boot loader working,
then reinstall them?
When you say U4 Pin11 goes low for 400ms, do you mean voltage drop?
If so what should it be or should I be looking at output of Pin 11 and 16
with a scope?
I have ordered a new soldering iron and solder sucker to clean off old solder.
I also ordered your DSO 094 to use in troubleshooting my DSO 138 and DSO 068.
When I get the DSO 094 I will try troubleshooting again. If there is something
you wont me to try now that will help you, I'm ready.
I am enjoying working on your equipment and look at it like a challenge.
bigxo
Re: Power Up Test DSO 068
Hi Bigxo,
I removed BOB1, BOB2 and BOB3. Closed JP1 and JP2 and powered from USB when having problems (of my doing). Worked through power up test 1 after fix, continued assembly and then the power up 2 tests, compensation capacity adjustment and have a working a scope. Now have a problem with BOB3 and working that through. Still to fully test with sig gen and with the PC application. It works and looks like a useful piece of Kit and delivered to the UK for $70 it is good value (less money than the smoothing caps and rects to repair my Tektronix 475).
I removed BOB1, BOB2 and BOB3. Closed JP1 and JP2 and powered from USB when having problems (of my doing). Worked through power up test 1 after fix, continued assembly and then the power up 2 tests, compensation capacity adjustment and have a working a scope. Now have a problem with BOB3 and working that through. Still to fully test with sig gen and with the PC application. It works and looks like a useful piece of Kit and delivered to the UK for $70 it is good value (less money than the smoothing caps and rects to repair my Tektronix 475).
Re: Power Up Test DSO 068
Jonathan Thanks for the info.
I will remove BOB1,BOB2 and BOB3 and close JP1 and JP2. I was using power from the USB.
I will try this and make a report and look forward to working with you. Sounds like you are far ahead
of me. I am 76 and it's been 25/30 years since I messed with a scope. I have lost much of my tech.
I'm building it for the challenge. I will update tomorrow.
bigxo (JIM)
I will remove BOB1,BOB2 and BOB3 and close JP1 and JP2. I was using power from the USB.
I will try this and make a report and look forward to working with you. Sounds like you are far ahead
of me. I am 76 and it's been 25/30 years since I messed with a scope. I have lost much of my tech.
I'm building it for the challenge. I will update tomorrow.
bigxo (JIM)
Re: Power Up Test DSO 068
Update on my DSO 068.
Now I have the Led and Buzzer working. I am at the end of Powering up test 2.
V4 reads 3.5V not 1.6V. I have checked the value of R9,R10 and R11 and re-soldered them and SW3.
How does U2B count so I can check pin 6 and 7 on U2B. Also how does SW3 count so I can check Pin 2.
Changing X1, X2 and x5 doesn't change the V4 reading?
Thanks
Now I have the Led and Buzzer working. I am at the end of Powering up test 2.
V4 reads 3.5V not 1.6V. I have checked the value of R9,R10 and R11 and re-soldered them and SW3.
How does U2B count so I can check pin 6 and 7 on U2B. Also how does SW3 count so I can check Pin 2.
Changing X1, X2 and x5 doesn't change the V4 reading?
Thanks
Re: Power Up Test DSO 068
Please see attachment for U2 and SW3 pin counting.
Re: Power Up Test DSO 068
I have downloaded the .rar app but can't open the file? I have windows 10.
Can I get the file in jpeg, are in another format.
Can I get the file in jpeg, are in another format.