[neonixie-l] Re: power supplies and radio interference
Sniffing around with E- and H-field probes, the largest contributor I can find are fast edges going over SPI lines on ribbon cable between multi-tube carrier PCB... quite obvious up to and beyond 1.5 GHz. I can see the digit fade activity on the spectrum analyzer... Noise for the first half second or so while cross fading between digits. Relative quiet the second half second. This with the probe right on the cable. All the noise significantly reduced just a small distance from the ribbon cable. Not much coming from the pcb proper with 4 layers including power and ground. I'll add a small value series resistor where high rep rate signals launch out onto cabling... slow the edges for clock and data lines. All of this while PWM dimming the display tubes at 15 kHz or so. Lots of HV switching that doesn't seem to be a large contributor. By *FAR*, the strongest signal I noticed in my shop was 10 MHz from a BNC cable running between my 10 MHz reference and a counter input. Hmmm... All the clocks, computers and assorted electronic gadgets may be part of the S7 noise floor I observe on 40M... will have to see what happens with the clocks and computers turned off! Bob -- 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/4f22b847-8f0e-46fc-bffc-5ca1d53b3d18%40googlegroups.com.
Re: [neonixie-l] So do you guys think I'll be getting this watch I just bought off ebay???
Luckily he refunded my money... I really should give him bad feedback but he sounds like a noob. Bill -- 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/CADToqn0iCpp5dmx4KtBFrxC7Op%3DHXZ55K_4LfP_QgPMNr3ME0w%40mail.gmail.com.
[neonixie-l] Re: power supplies and radio interference
Oscillations and switching signals are not enough on their own to create RFI. They have to be radiated. Shielding is a common way to reduce emissions (and also to reduce susceptibility to incoming interference). I always use twisted-pairs for my power cabling, and when I have to use ribbon cable for signals, I try to straddle the clock signals with a static signal, or ground, when possible. In extreme cases, which I doubt exist in nixie clocks, you need to use differential pairs. Ground loops are another source of trouble, which is why you want to bring all grounds together at a single point. If you have ground carried thru 2 or more paths, you may have introduced a ground loop if the paths are not identical. -- 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/57430fbd-de84-4cbf-bd11-4c55f53ef852%40googlegroups.com.
RE: [neonixie-l] So do you guys think I'll be getting this watch I just bought off ebay???
Naaa, it means he screwed up. He only had the one item listed. It means, he wants $399 plus shipping for it. Not $1. So, you can agree to pay $399 or cancel the winning bid. Michail Wilson 206-920-6312 -Original Message- From: neonixie-l@googlegroups.com [mailto:neonixie-l@googlegroups.com] On Behalf Of johnk Sent: Thursday, August 15, 2019 11:46 PM To: neonixie-l@googlegroups.com Subject: RE: [neonixie-l] So do you guys think I'll be getting this watch I just bought off ebay??? It means that he wanted to list "quite a few" items and had to use low starting prices. I guess the one in question didn't get bidded-up. The aggregate list value meant that he chose to risk not starting high. Or am I missing a point here? John k -Original Message- From: neonixie-l@googlegroups.com [mailto:neonixie-l@googlegroups.com] On Behalf Of Bill Notfaded Sent: Friday, 16 August 2019 15:38 To: neonixie-l Subject: RE: [neonixie-l] So do you guys think I'll be getting this watch I just bought off ebay??? Got this from the guy: New message from: zhch-12 (7) hi,so sorry ,one thing to note is that because of ebay's restrictions on new sellers, the maximum price of the articles published can only be $200, This month's quota is running out.and the real price is $399. What the heck does that mean? Well this guy started out on the wrong foot for sure. I almost feel sorry for him. Bill -- 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/6be738ed-3d93-4110-9e13-e4eb9357dbc1%40googlegroups.com. -- 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/004c01d553fe%243f460650%24bdd212f0%24%40internode.on.net. -- 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/01d5543b%24d9f31d90%248dd958b0%24%40com.
[neonixie-l] Re: power supplies and radio interference
My three B7971 clocks all produced RFI in the AM and SW radio bands, and I kept my radios at least 5m away. They were based on the CT7001 clock chip, so the MUX rate was about 2 KHZ. The RFI (and the acoustic singing from the tubes) seemed to change with the digits displayed. I assumed that it could be blamed on the switching of the HV on the tubes. Someone once suggested that the RFI came from the SMPS, but that is unlikely since I used old-fashioned linear supplies. In hindsight, I realize that I did not put a choke on the power cord, which might have helped. The moral of the story is that not all RFI necessarily comes from the power supply. -- 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/c81e4c7c-2950-4a1e-a96a-02329fcebdae%40googlegroups.com.
RE: [neonixie-l] power supplies and radio interference
I have several AM and FM radios and I have not experienced any noticeable interference from the various nixie clocks. On the other hand, I have experi nc d quite a lot from various LED lights and laptops. All of it is typically short range (several feet/meters). This article discusses a radio battery replacement (these batteries were 90V!): https://www.dos4ever.com/battery/battery.html -- 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/26efc12c-16c3-48ad-ab46-46a8a9005994%40googlegroups.com.
