I bought myself an old Revox B77 that needed some fixing. Mainly as a fun project, I have always wanted a two track high speed B77. Among other things the left VU meter was broken. The spool winding in it was broken and despite my best efforts I just couldn't get a hold of the tail end of the extemely thin spool wire to re-attach it. So looking around on the internet for an oem spare part VU meter I found that they have been out of production for a while and the prices have sky rocketed. With shipping and VAT just one meter would cost me $250. And since it was said that, in worst case, they can differ ever so slightly in color and look, there was a small risk that I would need to buy two. So I decided why not have a bit of fun instead designing some pcb with schematics and code, as yet another hobby project!
All files are here on GitHub for you to order an empty pcb, solder paste stencil, the front panel (which also is just a regular pcb) and the electronic parts for you to assemble, solder and load the code on to. If soldering surface mount parts isn't your thing you can always check with me if I happen to have an extra spare board or two, this is me: [email protected]
First long press the front panel button once and then toggle through all the color schemes with short presses. To save your choice long press again.
First long press the front panel button twice and then toggle through the different brightness levels with short presses. To save your choice long press again.
First long press the button three times and then toggle through the below modes with short presses, preferably with music playing so you can differ between the modes. To save your choice long press once again. Display modes available are:
- VU (dot)
- VU (bar)
- PPM (dot)
- PPM (bar)
- VU (bar) and PPM (dot)
First long press the button four times and then toggle through any available screen savers. After each short press the current choice will be shown for two seconds. The "screen saver OFF" option will just show the normal meter. To save your choice long press once again. And yeah, it is not a screen saver in the real sense of the word, it's just some fun color schemes that can be activated when there has been no input signal for a while.
There is a timeout when in programming mode, if no button is pressed at all for 15 seconds the screen will blink once and you will be back in normal mode. If you haven't long pressed to save your current choice any change will be ignored.
YouTube videos:
In the pictures below the display is in program mode (shown by a white LED being turned on in the lower part of left display). Different color schemes are easily added, some distinct and some more oddball color schemes are already in the code.
