Oh, since I am turning on one anode at a time, by the time I get back to the same anode, i have gone through 5 more 2ms steps so it has been 10ms, right? Is that close enough, or should i adjust it so that it is 18ms, which would make the 1.8ms on time 10%?
On Tuesday, June 6, 2017 at 1:12:52 PM UTC-4, GastonP wrote: > > OK you don't need to shout to be heard in this list. :) > > 1 - You can safely assume that "Pulse Voltage" is the one supplied by your > Power Supply. It is higher than the one needed for non-multiplexed > operation to guarantee a faster strike. > > 2 - Both modes A and B are safe from an operational standpoint and are > given as indicators of how far you can go with current for the target time > and duty cycle (that's how PWM translates in this case). > What it means is that for each 0.1ms a tube is on at 10mA you must wait > 0.9ms before turning it on again or you will burn its life away quite > quickly. The same is valid for mode B with 1ms and 5mA: you must wait 9ms > before turning that tube again on. There is a turn-on delay and also a > turn-off delay so not all of this wait-time is really so. As a reference > you can read this > <https://www.google.com/url?q=https%3A%2F%2Fthreeneurons.wordpress.com%2Fnixie-power-supply%2F&sa=D&sntz=1&usg=AFQjCNHxneOv7sG1QWaYlQdvBckSy8iKgg>, > > from Mike Moorrees "Pile of poo" which is an extremely good guide to > multiplexing nixie tubes and quite the opposite to his name choice :) > > You need to be careful and stick to what the specifications say regarding > to maximum voltage and currents, specially when multiplexing, or as I said > before, you risk to burn your tubes lifetime quite quickly. > > On Monday, June 5, 2017 at 11:09:55 AM UTC-3, scotth wrote: >> >> The tubes I'm using for two different clocks are IN-4s and IN-8s. I found >> the pulse specs you referenced on the IN-8 datasheet, but not the IN-4. On >> the IN-8 datasheet, it lists two different modes, A and B. For mode A, >> which is a pulse duration of 0.1ms, it gives a pulse Voltage of 200V and >> current of 10mA. It also lists a PMW of 10%, what does that mean? >> >> For mode B, which has a pulse duration of 1-2ms, it recommends 200V at >> 5mA and the same PMW. Which mode should I use? >> >> Is the pulse Voltage the same as my input voltage before my transistors? >> >> I will try to measure what current I am at later today. >> >> Thanks! >> >> On Monday, June 5, 2017 at 7:13:04 AM UTC-4, Tomasz Kowalczyk wrote: >>> >>> With most DC voltmeters you can safely assume that it measures the >>> average. So having average voltage drop on anode resistor and resistance >>> you can calculate average current, and then multiply it by 6 (if there is a >>> dimming/anti-ghosting dead time between tubes, you might want to take it >>> into account) to get the pulse current. >>> Nixie tubes can operate in multiplexed mode with pulses of current >>> higher than nominal current - as long as you aren't pushing average current >>> over the nominal current, it should be OK. >>> In IN-18 datasheet I found information, that the average current in >>> pulse operation should be a bit lower than during DC operation. >>> >>> Anyway, if your tube is specified for 2mA and you multiplex 6 tubes, I >>> think you can safely use 5-6mA pulses (~1mA average current) without >>> damaging the tube. But it would be less guessing and more solid information >>> if you would specify which tubes are you using. >>> >>> W dniu poniedziałek, 5 czerwca 2017 04:06:15 UTC+2 użytkownik scotth >>> napisał: >>>> >>>> First of all, thanks for accepting me to the group! >>>> >>>> I've built a functioning nixie clock that uses a nixie driver to >>>> multiplex all six numbers. Due to my inexperience, I just figured out the >>>> resistor that I needed to drive a single nixie tube at the correct voltage >>>> an current, which landed me at 22kOhms. However, as I'm sure you all >>>> know, >>>> my numbers were much dimmer once i got the multiplexed clock working with >>>> the same 22k resistors. Because of this, I decided to check the voltage >>>> drop and current of my nixies and got some numbers that can't be correct, >>>> as it is below the operating specs of the tube. Is it some sort of >>>> average >>>> or something? >>>> >>>> I've seen another thread on here where this is mentioned and I learned >>>> that I could get a more accurate reading of voltage and current using a >>>> scope (which I don't have). What I'm wondering is, is there a way to >>>> calculate what the current should be without measuring it? I'm not >>>> horribly dissapointed that the numbers are dimmer than driving a single >>>> tube, but I'd like to make sure I'm operating at the nominal current in >>>> order to maximize my brightness without significantly decreasing the >>>> expected life of the tubes. Any help is greatly appreciated! >>>> >>>> Below is a picture of my anode driving transistor circuit (?) not sure >>>> what the best way to word that is. >>>> >>>> >>>> <https://lh3.googleusercontent.com/-Pw6L5BQQbpU/WTS8TDyz4QI/AAAAAAAAAWs/-k91FOy1jiEE3Dirye3vQ5PH8oK1_ugLwCLcB/s1600/Capture.JPG> >>>> >>>> -- 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 post to this group, send an email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/8d0fc000-d26c-4983-8988-98763fc84b04%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
