Good point, I only did a short test with real tubes…
I’m currently modifying my through-hole clock boards, replacing the mc34063 stuff with the small DA2032 psu. When the new board is finished, I will check for singing tubes. Maybe you can solve the problem modifying the 140K resistor with another value to change the switching frequency. I had two identical boards, both with 140k 1% resistor, one switching with 85kHz, the other one with 110kHz, don’t know why. By the way, 110kHz seems to be a good value for good efficiency. Am Samstag, 3. August 2019 10:32:07 UTC+2 schrieb jörg: > > Hi, I've build pretty the same powersupply with the DA2032 and LT3757. I > love the small formfactor possible. > Unfortunately I'm experiencing singing Tubes after a while, if the PS is > going warmer. About 35 degrees C. > Using coolant spray, the singing disappears. > Question: Did you have effects? > > Anyway, I will investigate further. > And, thanks a lot for sharing. > -- 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/430ef150-42c3-4364-9e2a-a0ae28440e73%40googlegroups.com.
