Actually, I'm not sure how I'd meet that 10% and stay within threeneurons' specs.
On Wednesday, June 7, 2017 at 8:49:52 AM UTC-4, scotth wrote: > > 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/cbd9e44d-a542-404d-9e21-e2632a97123d%40googlegroups.com. For more options, visit https://groups.google.com/d/optout.
