Keyboard Shortcuts
ctrl + shift + ? :
Show all keyboard shortcuts
ctrl + g :
Navigate to a group
ctrl + shift + f :
Find
ctrl + / :
Quick actions
esc to dismiss
Likes
- Neonixie-L
- Messages
Search
Re: First Oscilloscope
"The Fool"
--- In NEONIXIE-L@..., Scott Burris <electroscott@...> wrote:
________________________________That's a good point. Since almost all of what I'll be measuring is microprocessors in the 5 MHz to 10 MHz range, what bandwidth would be workable. I had been thinking the lowest I could find around 20 MHz. Is that too low to be thinking of? Should I be looking at something higher? Thanks for the suggestions so far. I've added them to my list to look at. |
Re: First Oscilloscope
Mike Harrison
On Mon, 5 Jul 2010 19:09:56 -0400, you wrote:
On Mon, Jul 5, 2010 at 4:38 PM, The Fool <unmitigated_fool@...> wrote:And you can hack it to make it 100MHz....I'll also nominate the Rigol DS1052E FTW. |
Re: First Oscilloscope
"H. Carl Ott"
On Mon, Jul 5, 2010 at 4:38 PM, The Fool <unmitigated_fool@...> wrote:
I'll also nominate the Rigol DS1052E FTW. Love mine. Around 400 bucks American. You can find it on Amazon.com. -- carl -------------------------------------------------------- Henry Carl Ott N2RVQ hcarlott@... |
Re: Laser Pointer Life
"Theodore Johnson"
I built one using inexpensive lasers
To make the laser react fast enough to display something interesting, I had to remove a lot of the over-voltage protection circuitry. But semiconductor lasers are very delicate because a lot of energy is lasing in a very small cavity. The laser burnt out in a few months. But at $7.00 each, easy to replace. Lasers designed for fast switching are much more expensive, at least when I tried this. Ted From: NEONIXIE-L@... [mailto:[email protected]] On Behalf Of Paul Guncheon Sent: Monday, July 05, 2010 12:28 PM To: NEONIXIE-L@... Subject: [NEONIXIE-L] Laser Pointer Life I am looking to construct a clock involving the use of a laser. I am thinking of an over the counter laser pointer. Can anyone tell me the average life and duty cycle of your run of the mill laser pointer? Thanks, Paul [Non-text portions of this message have been removed] |
Re: First Oscilloscope
Scott Burris
You didn't mention bandwidth figures, but assuming you are looking for a digital
scope, in that price range, look at the Rigol DS1052E: $399, 50Mhz or the Instek DS-1062A (the A suffix is important): $415, 60Mhz I have the Rigol scope and love it, although I ordered it from an Ebay seller in China, rather than domestically. Scott ________________________________ From: The Fool <unmitigated_fool@...> To: NEONIXIE-L@... Sent: Mon, July 5, 2010 1:38:50 PM Subject: [NEONIXIE-L] First Oscilloscope I am planning on purchasing my first new oscilloscope since the Heathkit one I built back in the 70's. I'm looking for recommendations and suggestions. My price range is somewhere around $500. I was thinking that a color LCD one would be a good choice. |
Re: RS232 for GPS on PIC (help!)
"fixitsan2"
--- In NEONIXIE-L@..., "msilv3r" <msilv3r@...> wrote:
So I could, assuming I was always connected, use a compare within this string to know when a second in time has occurred. More than likely you will find that the NMEA sentence is transmitted once per second, on each one second epoch. Some GPS modules also output a 1pps signal with a high degree of accuracy associated with it, but generally your eye wouldn't be able to determine any difference, so sticking with receiving the NMEA sentence at the rate of 1Hz ought to keep you spot on. |
Re: Laser Pointer Life
David Forbes
On 7/5/10 9:27 AM, Paul Guncheon wrote:
I am looking to construct a clock involving the use of a laser. I amWe use these in a spectrometer at the radio telescope I work at. They last about 30,000 hours, then the emission loses its spectral purity as the mirror erodes. -- David Forbes, Tucson AZ |
Re: Laser Pointer Life
michail1@...
Run of the mill = Laser LED (not HeNe)
toggle quoted message
Show quoted text
cheap keychain one. Ok, I setup one to point at my viewhole on my front door. Runs 24 hours a day. That was about 5 years ago. No, I have no good reason for doing it, but it was setup and never taken down. So, it might give you an idea. Only off time is when the power goes out. Just a fast response as a time estimate. Michail In a message dated 7/5/2010 9:28:03 A.M. Pacific Daylight Time,
pguncheon@... writes: I am looking to construct a clock involving the use of a laser. I am thinking of an over the counter laser pointer. Can anyone tell me the average life and duty cycle of your run of the mill laser pointer? Thanks, Paul [Non-text portions of this message have been removed] |
Re: Some updates
"jensboos"
Hi Dieter,
toggle quoted message
Show quoted text
nice pictures, I admire your photographer skills ;-) I would love to see the IN-2 clock. If it is nice and tiny enough I would nearly be tempted ;-) Best regards, Jens --- In NEONIXIE-L@..., "Dieter Waechter" <dieter@...> wrote:
|
Re: RS232 for GPS on PIC (help!)
"jerry"
_____
From: NEONIXIE-L@... On Behalf Of Alex Rubli (YHO) My five cents: i would use the $GPRMC protocol it looks like this $GPRMC,140003.242,A,4717.1126,N,00833.7862,E,0.03,80.59,010201,,*36 this has a flag to tell you that the GPS is "locked" and so you can be sure that the time is correct (don?t rememeber which one the "flag" is), I also remember that this protocol shows the correct reading only after having info for at least 3 satelites. I am no expert, and did this long tome ago, I recall having faulty readings with other protocols make a NMEA $GPRMC google search. I also encourage you to disable the other protocols on your reciever, it might flood your buffer _____ A means valid V means invalid Jerry Wb9jfr No virus found in this incoming message. Checked by AVG - www.avg.com Version: 9.0.830 / Virus Database: 271.1.1/2982 - Release Date: 07/04/10 13:35:00 |
Re: Transistor as On/Off Switch for Muxing - Why use two?
"threeneurons"
Use the circuit that David has shown. The resistor values can be varied a bit, but use them in all the places shown. They are all important.On 7/2/10 7:03 PM, msilv3r wrote: The 'one transistor' circuit, you described is an 'emitter follower', which has NO voltage gain. The emitter will roughly follow the base, so the voltage will never exceed 5V of the base (actually ~4.3V). The voltage on the collector can be 6V or 200V, but the emitter will follow the base. Remember for a transistor to turn ON there needs to be a current flow from base to emitter. This can only occur (for an NPN) if the emitter voltage is less than the base voltage, by the forward voltage drop of silicon. That voltage being ~0.7V at room temperature. An 'emitter-follower' circuit has current gain, but no voltage gain. In short, no worky. Google it, if you don't believe me. |
Re: RS232 for GPS on PIC (help!)
"Alex Rubli \(YHO\)"
My five cents:
i would use the $GPRMC protocol it looks like this $GPRMC,140003.242,A,4717.1126,N,00833.7862,E,0.03,80.59,010201,,*36 this has a flag to tell you that the GPS is "locked" and so you can be sure that the time is correct (don?t rememeber which one the "flag" is), I also remember that this protocol shows the correct reading only after having info for at least 3 satelites. I am no expert, and did this long tome ago, I recall having faulty readings with other protocols make a NMEA $GPRMC google search. I also encourage you to disable the other protocols on your reciever, it might flood your buffer regards Alex [Non-text portions of this message have been removed] |
Re: Nixie watch on auction for charity
Joe Croft
I'm betting if it had the GPS module you would be replacing the batteries
toggle quoted message
Show quoted text
regularly ;). -joe On Sunday 04 July 2010 08:30:28 m82a1pa wrote:
Well, I didn't get it since I bought one around the first of March. |
Re: Nixie watch on auction for charity
"m82a1pa"
Well, I didn't get it since I bought one around the first of March.
I'm a little disappointed in mine. I haven't had to change the battery yet. And it has only gained two seconds since I set the watch. So I never get to open it and do anything to it. Except wear it. Are you sure there's not a GPS module in it? |
Re: Nixie watch on auction for charity
michail1@...
You know. I have to agree.
toggle quoted message
Show quoted text
Mine is just terrible too. I think it keeps better time than my Citizen ATom watch. My Citizen gets more attention, because I have had to mail it in twice for repair. My DF Nixie watch only gets attention from people noticing it. Michail In a message dated 7/4/2010 5:31:20 A.M. Pacific Daylight Time,
ml.denison@... writes: Well, I didn't get it since I bought one around the first of March. I'm a little disappointed in mine. I haven't had to change the battery yet. And it has only gained two seconds since I set the watch. So I never get to open it and do anything to it. Except wear it. Are you sure there's not a GPS module in it? |
Re: Transistor as On/Off Switch for Muxing - Why use two?
David Forbes
On 7/2/10 7:03 PM, msilv3r wrote:
C - HV PSU -> collectorMike, The reason to use two transistors is that you need a level translator to isolate the PIC output at 0-5V from the anode of the nixie tube which sees up to 180V. Otherwise you'll find that you either can't turn on the anode or that you can't turn it off or that your PIC blows out. The standard approach used in most nixie clocks is an NPN transistor driven by the PIC whose collector controls the base of a PNP transistor that gates the tube anode. Here's my circuit: You can use an MPSA42 for the NPN and an MPSA92 for the PNP; they cost less than the Zetex transistors I used. I recommend the resistor values in the above schematic, as it worked flawlessly for me. Others have had good luck with different values. -- David Forbes, Tucson AZ |
to navigate to use esc to dismiss