So do I, I have a 3LO38i waiting for a while in his box. Le mardi 27 février 2024 à 05:45:37 UTC+1, Richard Scales a écrit :
> I too would be interested in a kit if you are considering making such a > thing available. > > - Richard > > > On Monday 26 February 2024 at 18:50:05 UTC paulvr wrote: > >> The flyback converter is built around the TI LM5156H. This IC was >> selected because it has an external mosfet, which means the voltage on the >> primary side can be increased considerably and the winding ratio does not >> have to be very high. An external mosfet generally also has better >> properties that improve efficiency. The chosen mosfet is very small and >> difficult to solder, as an alternative I can recommend the IPP17N25S3-100. >> The flyback transformer is from Würth from the WE-FLEX series. The >> insulation voltage is not great considering the output voltage, but I have >> not been able to detect any problems. The achieved efficiency is between 70 >> and 80% depending on the input voltage and output power. The output power >> easily reaches 6 to 7 Watts depending on the input voltage. Minimum input >> voltage approximately 9 Volts, maximum 16 Volts limited by the LM5156H. >> The filament power supply is built around TI's SN6507. That is a fairly >> new IC and one of the few forward converters I have found that can supply >> up to an ampere and more. Together with a Würth push-pull transformer it is >> a good combination to supply the 6.3 Volt up to 600 mA. The SN6507 has >> programmable current limiting, but that doesn't really work well with the >> filament which has a very low start-up resistance. The converter remains in >> current limiting mode when the programmed current is too low. Efficiency in >> combination with the buck converter approximately 80%. >> >> Op maandag 26 februari 2024 om 17:30:59 UTC+1 schreef David Forbes: >> >>> Paul, >>> >>> This is quite a nice project. It looks like a very clean display. >>> I have run out of the custom transformers I had made in 2006, and I'm >>> quite interested in using off-the-shelf ones in the future. Would you be >>> willing to share a schematic of what you made? >>> I also appreciate using SVG rather than rolling your own graphics. >>> That's a nice standard solution that makes sense in this age. >>> >>> >>> On 2/26/2024 2:12 AM, paulvr wrote: >>> >>> This is my first post in this forum and I would like to introduce you to >>> my version of the scope clock. Mainly inspired by the work of David Forbes >>> and Grahame Marsh. >>> The work is not finished yet, but I have reached a milestone for myself >>> in that all components are on one PCB and only one voltage source is >>> required, nm. 12 volts DC. >>> The high voltage is made using a standard Würth WE-flex transformer, >>> plus and minus 250 Volt. The filament voltage is provided by a buck and >>> forward converter and a standard Würth push-pull transformer (6.3 Volt to >>> 600mA). >>> The MCU is an STM32G491, mainly chosen because of the integrated 12-bit >>> DACs. The image composition is completely DMA controlled and works >>> independently of the CPU, which therefore has a lot of time for other tasks. >>> The characters and graphic shapes are encoded as SVG path. >>> An ESP32 has been added to achieve the correct time according to the >>> NTP. Operation is entirely via a web server running on the ESP32. The >>> software is not finished, and not all functions work (work in progress). >>> The next step is to try out other CRT tubes and make a housing. >>> >>> Regards, >>> Paul >>> >>> -- >>> 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/4e60fa43-a9b5-40b5-8381-5a968b45d480n%40googlegroups.com >>> >>> <https://groups.google.com/d/msgid/neonixie-l/4e60fa43-a9b5-40b5-8381-5a968b45d480n%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+unsubscr...@googlegroups.com. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/5d9d608d-37db-4629-a7d9-01fdcec0d66cn%40googlegroups.com.
