Thanks Martin, I'm OK with using a transformer. I would prefer something off the shelf, but perhaps I should just wind my own anyway. Seems like a useful skill to have.
As with a lot of these things, I find that I have a lot of questions. For example, this statement: "The transformer is 1:1, center-tapped. Since the output is to be 300 mA max, the magnetizing current at the input should be no more than 30 mA. I will try 10 mA" First of all, how does he get a 10:1 ratio of output current to 'maximum magnetizing current'. Second, what is 'magnetizing current', does he just mean current through the primary? Then he introduces terms in equations without defining them - they are probably obvious to the initiated (which I am not unfortunately). For example, Xl in L = Xl/2/PI/F and Al in N = (L*1e6/Al)^.5. Then having calculated the required number of turns, he just ignores that and goes with something much larger. On Friday, August 20, 2021 at 5:51:17 PM UTC-4 Dekatron42 wrote: > There is a nice article in NutsVolts magazine: > http://www.nutsvolts.com/media-files/Forum-Articles/QA_201110.pdf where a > powerful driver is shown, needs a small transformer but seems to be well > designed with equations for calculations of the transformer. > > /Martin > > On Friday, 20 August 2021 at 21:37:46 UTC+2 Hannah Mishin wrote: > >> Theres a section on filament driving in my blog here: >> >> https://hannahmishin.com/blog/2017/4/30/russian-tri-color-vfd-indicator-clock >> >> *Hannah Mishin* >> * She/her/hers* >> <http://hannahmishin.com/> >> >> *hannahmishin.com* <http://hannahmishin.com/> >> >> >> >> On Fri, Aug 20, 2021 at 1:48 PM Toby Thain <to...@telegraphics.com.au> >> wrote: >> >>> On 2021-08-20 12:58 p.m., Paul Andrews wrote: >>> > I'm designing a clock for DT-1704 tubes and am stumbling at the >>> filament >>> > drive stage. They want 1.6V. I want to power it from 5VDC. ... >>> > >>> >>> FWIW I've used LM2575 1A adjustable step down for DC filament voltages >>> in that range. >>> >>> --Toby >>> >>> >>> > ... >>> > >>> > So I would appreciate any suggestions for what direction I should take >>> > here. I have too many options and no clear criteria. >>> > >>> > -- >>> > 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 neonixie-l+...@googlegroups.com >>> > <mailto:neonixie-l+...@googlegroups.com>. >>> > To view this discussion on the web, visit >>> > >>> https://groups.google.com/d/msgid/neonixie-l/860d4d78-c807-415e-a740-b576a4b5d18cn%40googlegroups.com >>> > < >>> https://groups.google.com/d/msgid/neonixie-l/860d4d78-c807-415e-a740-b576a4b5d18cn%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 neonixie-l+...@googlegroups.com. >>> To view this discussion on the web, visit >>> https://groups.google.com/d/msgid/neonixie-l/ce44816f-120e-abae-060f-fe062d24f836%40telegraphics.com.au >>> . >>> >> -- 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 neonixie-l+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/3ce4276a-9c4d-40e3-9730-63534f1bb238n%40googlegroups.com.
