Hi Morris, Is the transformer sound also there if the steel case is removed? May be the case is working as a speaker membrane... In that case you can consider to make an aluminium or plastic case. To muffle the sound you can use those bituminous plates also used for deadening resonance in car sheet work. 3M has them in their program and you will get them in most car parts shop and also damage repair business. eric _____
From: [email protected] [mailto:[email protected]] On Behalf Of Morris Odell Sent: zondag 10 augustus 2014 11:01 To: [email protected] Subject: [neonixie-l] Re: Sperry radar clock now working! Hi all, Latest progress on the Sperry radar clock - I found a very helpful transformer manufacturing shop whose owner was happy to vacuum impregnate and bake the howling transformer for me. Alas, it only made a very small difference, if any. It sounds like the problem is magnetostriction in the core so there's no easy solution. I've rubber mounted it to try to stop the rear chassis panel from acting as a sounding board but that's all I can do I think. Hopefully it will be quieter when it's all buttoned up. Right now I'm working on a PCB which will contain a PIR motion detector and also a Xbee wireless receiver to pick up the GPS data that I have sent around my house. I also have a question - among other things the PIR motion detector switches the power to the CRT heater. Is it worth dribbling a little bit of current through the heater when it's off so that it heats up faster when the PIR senses an observer? If so, how much? The CRT heater draws 300 mA at 6.3 volts when it's working but takes about a minute to get to full emission. Will preheating it like that shorten its life significantly? Any opinions much appreciated, Thanks, Morris On Monday, July 14, 2014 7:02:47 PM UTC+10, Morris Odell wrote: Hi all, I've got the clock displaying time now. The video shows it upside down on the bench so it's at a few minutes past 12. That howling power transformer is a distraction, I'll have to wrap it in some sound absorbing material especially as I like to add Westminster chimes to my clocks :-). The next step is to put it all together and tidy it up! https://www.youtube.com/watch?v=tL3840bE9Cs Morris -- 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 email to [email protected]. To view this discussion on the web, visit https://groups.google.com/d/msgid/neonixie-l/99d0f7d2-28a1-41d6-8d57-c959754 607fb%40googlegroups.com <https://groups.google.com/d/msgid/neonixie-l/99d0f7d2-28a1-41d6-8d57-c95975 4607fb%40googlegroups.com?utm_medium=email&utm_source=footer> . For more options, visit https://groups.google.com/d/optout. -- 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/!%26!AAAAAAAAAAAYAAAAAAAAAPDddShx705MuX20yCpp0vvCgAAAEAAAALXJgCJky3JMqSPJunzIgJcBAAAAAA%3D%3D%40zeelandnet.nl. For more options, visit https://groups.google.com/d/optout.
