one more question:
My clock happens to "flicker" occasionally: it looks like it blanks all tubes for a fraction of a second sometimes. I did not find an regularity, besides that the most prominent of these events happens at the turn of a minute, i.e. every full minute.
Edit: Nevermind: Rremoving the RTC -> flicker is gone. I had an RTC and WIFI time provider at the same time.
Can you positively confirm that running both the RTC and WiFi at the same time caused the clock to flicker?
I have a couple of clocks running with that configuration, and I have not noticed it. IfI'll move one like this into my permanent line of sight to see if I can observe it. It's annoying when that happens.
Yep it is really there for me....
As soon as I connect an RTC, when switching from e.g. 17:30:59 to 17:31:00, shortly before going to 17:31:01, there is something that looks like a blank period or maybe only some interference that mimics a blank period. I'd estimate the length to be below 50 ms. Maybe I'm just overly sensitive. I did not see it without RTC. Even tried two RTC modules (all cheap chinese DS3231) and it was there at both.
Maybe not visible with other tubes?
Could this be the time when performOncePerMinuteProcessing() is called? There are two calls to RTC related functions from within this.
Well, yes, I think it is something to do with that, but the delay must be quite large for it to cause a flicker. Normally we should get all that I2C stuff over in less than a millisecond, so it should not hold things up. I'm going to have to do some tests.
OK, now a real problem:
When switched on, the clock emits a high pitch sound which increases in frequency. During this phase, the tubes start to light with increasing brightness. However, after maybe 2-3 seconds, the sound stops, everything goes dark (also the LED in the power-regulator stage) and after another second everything starts all over again with the high pitch sound. MOSFET and 100µH inductor get hot after a while in this mode. I think the wall-power supply goes into over-current protection and switches off (specifications 3A@12V!).
What I tried (and what didnt work):
-Disconnect everything but the button
-Switching power supplies
-Pulling tubes (that only prolongs the duration of above sequence)
-Replacing MOSFET (got very hot after a while, but was not the cause)
-Replacing capacitor C3 (220µF 35V) (only because it looked suspicious, but obviously was nothing)
Any ideas? Maybe the 100µH inductor? (Don't think that it would show up like this). Something with the switching frequency of the HVD not being high enough? What would that frequency be normally? I have a multimeter which is supposed to measure up to at least 200 kHz.
Last edit: 1 year 3 months ago by Phil_Mod3. Reason: Added wall-power supply specs. Added more speculative causes.