On the MK1.5 circuit (and the MK2 circuit, since it is basically the same plus another transistor driver [I think.. I haven't looked lately])... It's easy. There is a resistor divider circuit that provides feedback from the power supply's output back to one of the pins on the MC34063(AP34063), I think it is the "sense" pin.. I can't find the schematic for this circuit because for some reason, Mike's skydrive nor the nixie file archive are crawlable by google. This is a big problem for the world at large! I'll figure out a way to get this schematic on google, no reason it shouldn't be [grumble,grumble - no wonder everyone thinks it is either 555 or MAX1771]..
Anyways, this pin sense pin is very simple. If it sees more than 1.25v, then it turns down the output, if it sees less than 1.25v it turns UP the output. So, you'll see a resistor divider circuit that is calculated to turn your target output voltage into 1.25v. Just adjust those 2 resistors so that your new target output voltage shows 1.25v to the sense pin on the MC34063. All done. No problem. I used the MC34063 for the powersupply in my VFD clocks as well, it was a breeze (thanks to Mike). I have no clue how this is accomplished with the 555 circuit, I'd guess either an advanced engineering degree or trial&error. [joking]. :) I was up all last night getting my new 80m antenna working [g7fek], so I just woke up. Sorry for the strange sense of humor & attitude. -Adam On Sun, Aug 7, 2011 at 11:02 AM, Eric1180 <[email protected]> wrote: > I plan on using a 555 or a AP34063 and i have a IRF510. But i don't know > what to adjust to get the voltage down. I think the plans you use to make > Nixie power supplies are called MK1.5 or MK2. it would be easier to figure > out what to adjust if i have a IRF710 and and i could just tinker around > till i find out what controls the voltage but since the IRF510 Transistor i > have cant handle 170v i don't know what to adjust. > > Could some one point me in the right direction or tell me what to adjust. > Thanks a lot. > > -- > You received this message because you are subscribed to the Google Groups > "neonixie-l" group. > To view this discussion on the web, visit > https://groups.google.com/d/msg/neonixie-l/-/B9zGC2Tr6vEJ. > To post to this group, send an email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/neonixie-l?hl=en-GB. > -- You received this message because you are subscribed to the Google Groups "neonixie-l" group. To post to this group, send an email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/neonixie-l?hl=en-GB.
