David, I need to consult you about the rubidium oscillator. I am wanting to set one up. Can you offer any hints or tips
on dividing down the osc. Freq. (10 mHz, I think it is, and typically powered by 24 volts DC). Any of your thoughts will be helpful. Thanks, Chuck ---- Original Message ---- From: "David Forbes" <nixiebu...@gmail.com> Sent: 4/19/2021 1:26:52 PM To: "NeoNixie" <neonixie-l@googlegroups.com> Subject: Re: [neonixie-l] CRISTAL + CAPACITOR = TIME DELAY HELP My Nixie watches have a variable 5-30pF capacitor on the crystal so that I can adjust the oscillator to exactly 32768 Hz. You could use a different value depending on your crystal characteristics. I use an old Hewlett Packard universal frequency counter, running in time period averaging mode, measuring the time period of 10,000 cycles of the oscillator. I connect an oscilloscope probe to the oscillator output pin on the PIC computer to achieve minimum loading of the crystal circuit. I have to adjust it to run a bit slow with the probe connected, to get proper timekeeping when the probe is removed. I can adjust it to within one second per week using this technique. I've done this on 2000 Nixie watches by now, so it works. On Mon, Apr 19, 2021, 1:23 AM MrThe50sanchez <the50sanc...@gmail.com> wrote: Hello Guys! I have a nice question to ask you guys if you can give me some help. I builded a Nixie watch, It works good, but I'm having a little bit of time delay, 1 min within 6 hours. At the first time, I had 6 min delay for 6 hours aproximately. I investigated the relation of the cristal and the capacitors you need to install with it. First, I had 22pF for a cristal that requires 12.5pF, giving me that 6 min delay for 6 hours, then, I realised these and installed 10Pf capacitor and the delay decreased to 1 minute for 6 hours, and I just ordered new capacitors of 12pF to get more closer to the manufacture requires, So I imagine that the delay is gonna get less. ·Is there any way to make this time delay shorter? ·Do you recommend me a tipe of cristal that is really acurate to install on my watch? Thanks a lot nixie lover's -- 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/7ce2b557-f652-44b2-a71f-ed75b96ea06fn%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/CAPbqtvfXMhwT4BZLp64Rn_1SpMxDa-46RBVcpLMgkb0-4fFxMw%40mail.gmail.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/202104191123137.SM1493329%40ADT-IM1.