Black Lives Matter - Action and Equality. ... Adafruit is open and shipping.
0

Ice Cube clock: flickering digit
Moderators: adafruit_support_bill, adafruit

Please be positive and constructive with your questions and comments.

Ice Cube clock: flickering digit

by N6BM on Mon Nov 10, 2014 4:43 pm

I completed the build of my Ice Cube clock and had no problems with the build or programming. The clock works fine and all of the digits display solidly, but two of the digits flicker. This relates to the number "0" with seconds (unit digit) and the number "3" in the unit digit with minutes - hours display OK. I thought it might be a cold solder joint and went back and inspected and re-heated the points in the display tube p.c. board and the main board. I'd like to know if this could be a defect in the tube segment or if it could be the micro-processor chip? Traces are good, no solder bridges and voltages outlined in the manual are checked with a digital Fluke meter - OK.

N6BM
 
Posts: 75
Joined: Mon Nov 10, 2014 4:22 pm

Re: Ice Cube clock: flickering digit

by adafruit_support_bill on Mon Nov 10, 2014 4:57 pm

If you post photos of the solder-sides of your boards, we'll take a look.
Another possibility is a marginal Q3. If you (carefully!) short together the first and third legs of Q3, does the flicker go away?

adafruit_support_bill
 
Posts: 78209
Joined: Sat Feb 07, 2009 10:11 am

Re: Ice Cube clock: flickering digit

by N6BM on Mon Nov 10, 2014 10:58 pm

Here's a photo of the two boards as requested. All digits are solid except just the number zero in the seconds and only the number 3 in the minutes...hours show OK.
I checked the position of the position of Q3 and it has the flat side as outlined on the board. I have not done a short between pins 1 and 3 until you look at the boards.
Attachments
display tube end.JPG
display tube end.JPG (220.3 KiB) Viewed 813 times
display pc board.jpg
display pc board
display pc board.jpg (148.68 KiB) Viewed 813 times
mother board.JPG
mother board
mother board.JPG (250.4 KiB) Viewed 813 times

N6BM
 
Posts: 75
Joined: Mon Nov 10, 2014 4:22 pm

Re: Ice Cube clock: flickering digit

by adafruit_support_bill on Tue Nov 11, 2014 6:47 am

Soldering looks mostly pretty good. There are a few questionable looking ones on the tube board circled below. The topmost one looks a little solder-starved. The two next to it look like possible cold-joints. Touch those up and see if anything improves. If things are still flickering, try the Q3 test.

http://learn.adafruit.com/adafruit-guid ... n-problems
Attachments
Capture.PNG
Capture.PNG (266.48 KiB) Viewed 806 times

adafruit_support_bill
 
Posts: 78209
Joined: Sat Feb 07, 2009 10:11 am

Re: Ice Cube clock: flickering digit

by N6BM on Tue Nov 11, 2014 2:00 pm

I re-soldered the points mentioned in your previous answer and I still had the flicker problem with two of the digits. I shorted pins 1 & 3 of Q3 and the two segments that flickered are fixed. The whole display is brighter as I would have expected. I should find a replacement of the marginal Q3 if you can send one to me or forward a link for purchase. Would their be a disadvantage of leaving the short between pins 1 & 3 and not bother with replacing Q3?
Bill

N6BM
 
Posts: 75
Joined: Mon Nov 10, 2014 4:22 pm

Re: Ice Cube clock: flickering digit

by adafruit_support_bill on Tue Nov 11, 2014 2:12 pm

Q3 cuts power to the tube heater when running on battery backup to avoid draining the battery. If you contact support@adafruit.com with a link to this thread we can send a replacement.

adafruit_support_bill
 
Posts: 78209
Joined: Sat Feb 07, 2009 10:11 am

Please be positive and constructive with your questions and comments.