Hi,
The first digit of the seconds display in missing, otherwise the clock works fine. I just cant seem to figure this out. Please help
Ice Tube Clock- 1st seconds digit blank
Moderators: adafruit_support_bill, adafruit
Please be positive and constructive with your questions and comments.
- russell 27
- Posts: 242
- Joined: Thu Sep 12, 2013 3:59 pm
- adafruit_support_bill
- Posts: 88091
- Joined: Sat Feb 07, 2009 10:11 am
Re: Ice Tube Clock- 1st seconds digit blank
A single digit missing is often traceable to a bad solder joint. If you post clear photos of the front & back of the boards we'll take a look.
- jarchie
- Posts: 615
- Joined: Sun Jun 24, 2012 2:16 pm
Re: Ice Tube Clock- 1st seconds digit blank
For the dim digit problem, I've never seen the digit so dim that it appears blank. The issue could be the flaky segment problem described in the second thread, but when the flaky segment problem affects a single digit, the digit usually works intermittently rather than being completely dead. When a single digit is completely dead, it's typically a dodgy connection from the VFD driver chip to the VFD tube--the connection controlling the grid of the bad digit. On these forums, the problem usually turns out to be a bad solder joint, as Bill suggests, but I've also seen bad connections within IV-18 tube itself.Russell 27 wrote:Take a look at these posts: Ice tube clock - last digit faint, ICE Tube Clock help.
But that kind of bad connection in the tube is unlikely given the method Adafruit uses to pretest their IV-18 tubes. Once in a blue moon, Adafruit will miss a short within the tube, but I've never seen them miss a bad connection.
I've never figured out why, but it's really easy to miss a bad solder joint in one's own work. If you post pictures like Bill suggests, we'd be happy to double check the build.Atomisk wrote:The first digit of the seconds display in missing, otherwise the clock works fine. I just cant seem to figure this out. Please help
- russell 27
- Posts: 242
- Joined: Thu Sep 12, 2013 3:59 pm
Re: Ice Tube Clock- 1st seconds digit blank
I wasn't implying anything in particular here. The posts I referenced were a start point. There are several references within those posts to other links, as well as, several photos of a great solder and assembly job. I'm not exactly certain which is meant by the 1st seconds digit, but it would be a grid anode connection and a voltage test could be performed there; looking for roughly 20- 25 volts under load. Actually you saw digits that were totally blank in the last post.
- jarchie
- Posts: 615
- Joined: Sun Jun 24, 2012 2:16 pm
Re: Ice Tube Clock- 1st seconds digit blank
I understand, and the links are useful for that. But I did want to make sure Atomisk knew that it's worthwhile to post photos of the build before replacing Q3.Russell 27 wrote:I wasn't implying anything in particular here. The posts I referenced were a start point.
Your first link describes the dim digit problem which is caused by low filament voltage; that's the problem I was ruling out. The second/last link is to a variant of the flaky segment problem, which seems to be a power oscillation issue of some sort. I agree that the flaky segment problem might be the underlying problem here, but also think that a bad solder joint is more likely.Russell 27 wrote:Actually you saw digits that were totally blank in the last post.
- russell 27
- Posts: 242
- Joined: Thu Sep 12, 2013 3:59 pm
Re: Ice Tube Clock- 1st seconds digit blank
There's no need to replace it. A quick jumper test could determine that immediately. This isn't a contest, simple tests are the way to go. It's really hard to know from the initial information.
- jarchie
- Posts: 615
- Joined: Sun Jun 24, 2012 2:16 pm
Re: Ice Tube Clock- 1st seconds digit blank
Alright, alright! You and Bill have this thread more than covered, so I'll just bow out at this point.Russell 27 wrote:This isn't a contest, simple tests are the way to go.
By the way, the jumper test Russell's referring to is described half way through his second linked thread.
- adafruit_support_bill
- Posts: 88091
- Joined: Sat Feb 07, 2009 10:11 am
Re: Ice Tube Clock- 1st seconds digit blank
@Atomisk - I hope we didn't scare you away. Both Russel27 and JArchie know this clock well. But it looks like we all interpreted the problem slightly differently and all offered different advice.
In general, the more detail you can provide up front, the faster we can identify the problem.
In general, the more detail you can provide up front, the faster we can identify the problem.
If it is the very last digit that is missing, Q3 may be the culprit. If you are referring to the second-to-last digit, it is more likely a bad connection & some photos would be the place to start.The first digit of the seconds display in missing,
-
- Posts: 2
- Joined: Mon Mar 10, 2014 1:35 pm
Re: Ice Tube Clock- 1st seconds digit blank
Thanks for the help I'll get some photos up asap
Please be positive and constructive with your questions and comments.