Getting 9.01V at D3

[pauldjagger]

Yes, I am using the supplied 9V adapter, with a UK/US plug adapter.

Repeating the readings again (in the sequence and at the points shown in the assembly instructions), I now get: 8.9V, 4.8V and 13.9V respectively and am able to consistently repeat that test with those values. The unit at least 'beeps' when I plug it in to the mains, unlike the previous one. I confirm these tests are conducted with the VFD chip installed and the tube removed.

[adafruit_support_bill]

I now get: 8.9V, 4.8V and 13.9V

OK. 8.9v is a lot better than 11.3v. 4.8 is still slightly on the low side for the output of the 7805. You might check to make sure your meter has fresh batteries.

What voltage do you measure on the end of R3 closest to Q3?

And post a photo of the solder-side of your tube board.

[pauldjagger]

I get 4.69V at the end of R3 (consistently). The meter has a brand spanking new (and tested) set of batteries. Will post a revised photo of the solder side of the PCB later today or early tomorrow.

[adafruit_support_bill]

4.69v sounds about right. When you post photos - include one of the small tube-board as well.

[pauldjagger]

After an interruption of several months, I have finally made time to check over all the solder joints and retouched most of them. The result is a working clock (yippee). I now just have to figure out why the right hand two digits in the tube are slight faded.

[adafruit_support_bill]

I now just have to figure out why the right hand two digits in the tube are slight faded.

This is mentioned in the FAQ. Because the bias voltage is DC, there is a gradient from one end of the tube to the other. One firmware modification that has been posted in this forum addresses the issue by changing the timing on the display multiplexing.

[pauldjagger]

Hmm, I did checked the FAQs (twice) for the Ice Tube and see no mention of dimming digits or how to cure them. I also check the Trouble Shooting Guide for the Ice Tube (likewise no mention). I checked also the comparison of Firmware, and there is no clear statement therein on which (if any) of the firmware options available address specifically the issue of dimmed digits.

I would appreciate a direct pointer to the resolution, as a search of this forum for the terms 'dim', 'dimming', 'dimmed', 'fade' and 'faded' produces lots of results, but no obvious discussion that leads to a solution that I can see.

[adafruit_support_bill]

The FAQ (last question) doesn't give a cure - just mentions the phenomenon:

At low brightness, the seconds are dimmer than hours

Unfortunately this is an effect of the way we drive the tube. It is not apparent at medium and high brightness

The thread which discusses the digit brightness mod is here: http://forums.adafruit.com/viewtopic.php?f=41&t=23586

[pauldjagger]

Thank you for that, I could not find the FAQ question you make reference to here until... I realised that you referred to the Ice Tube FAQs on the Ice Tube product page, not the FAQs for Ice Tube in this Forum!

Anyway, I now have my USBtinyISP AVR Programmer, all assembled and ready to go. I have downloaded some suitable firmware, but try as I might I find no simple set of 'follow the bouncing ball' instructions for those lacking experience in learning how to program the Ice Tube from the command line. The various web pages/forum discussions on the AVR Programmer and firmware options seem to rely on the maxim 'use the source Luke', without explaining how (for novices).

Any pointer to a suitably idiot proof set of steps for programming the Ice Tube would be appreciated.

[adafruit_support_bill]

We don't have a complete tutorial for firmware mods, since many of the mods involve hardware too. This page steps you through the download process once you have the hex file. Are you starting from a hex file, or from the source?