That is the problem with my MM5311 based B7971 clock that I built 40 (ugh) years ago. The multiplexing causes the tubes to whine. It did not bother me much when I was younger but as I got older and was not sleeping as soundly, the noise became bothersome. I tried changing the frequency but its stable operating frequency range is smack dab in the middle of human hearing. I leave it off most of the time now except for special occasions. I have debated looking for a direct drive B7971 clock kit and using the tubes with it. The six tubes I have installed on it are far more valuable than the rest of the clock.
Robert On Wednesday, January 8, 2020 at 1:55:42 PM UTC-5, philthepill wrote: > > Some people are very sensitive to humming and ticking sounds especially at > night. Back in the 1070's I bought an Accutron wrist watch with the tuning > fork time base. At night the humming was loud enough that I put it in > drawer on the far side of my bedroom. My first LED clock has always been > my favourite ( from a Radio Shack ad fir the boards. ) - totaly silent it > still works great today. > > Pharma Phil. > > ---------- Original Message ---------- > From: gregebert <[email protected] <javascript:>> > Date: January 8, 2020 at 12:13 PM > > Our bedroom clock has 8 tubes (b7971), and is PIR activated. Needless to > say, it's very bright when on. I set the timeout to 100 seconds, and I dont > ever recall being awakened by the display turning-on. A future project is > to modify the code so it reports how many times the PIR sensor was > triggered during the night. I dont use any kind of dimming, mainly because > people have reported audible noise from tubes that use PWM dimming. > > Both of our kids (now grown and moved-out) built 6-tube clocks with b5092 > tubes, and they never complained about the seconds ticking-away at night; > they actually liked it, sort of like counting sheep, etc. > > I think flip-dots would drive me crazy.....even the mechanical flip-style > clocks that were prevalent in the 1970's were a bit annoying. > > > > -- > You received this message because you are subscribed to the Google Groups > "neonixie-l" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected] <javascript:>. > To view this discussion on the web, visit > https://groups.google.com/d/msgid/neonixie-l/bde66e6a-11c2-43a4-850f-0c85ca3faffb%40googlegroups.com > > <https://groups.google.com/d/msgid/neonixie-l/bde66e6a-11c2-43a4-850f-0c85ca3faffb%40googlegroups.com?utm_medium=email&utm_source=footer>. > > > > > > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/84b17e15-e83e-47cf-bf68-33eec64fa886%40googlegroups.com.
