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Electronics => Projects, Designs, and Technical Stuff => Topic started by: Hugoneus on June 13, 2011, 09:46:04 pm

Title: Camera Flash Circuit and Nixie Tube Tutorial
Post by: Hugoneus on June 13, 2011, 09:46:04 pm
For those interested, our new episode is about the camera flash circuit and nixie tubes. I analyze the the flash DC-DC converter at the schematic level and use it to power a nixie tube. I also measure the efficiency of this system. Please visit:

http://www.TheSignalPath.com (http://www.TheSignalPath.com)

Thanks!
Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: Kiriakos-GR on June 13, 2011, 10:04:46 pm
Well I belong to the Fun club of Olympus digital Full TTL .
I have no interest about old tubes..   :)

Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: Hugoneus on June 13, 2011, 10:09:19 pm
Hi,

This tutorial analyzes the schematic of the flash circuit found in disposable cameras. The principle of operation, measurements, etc. It also shows how this circuit can be used to power a nixie tube. It is not about different flash types. ;)
Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: djcrunkmix on June 14, 2011, 02:58:00 am
This is absolutely fantastic. I can ditch TV cable and watch EEVBlog and your channel all day long :)

 ;D
Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: Hugoneus on June 14, 2011, 03:41:04 am
Quote from: djcrunkmix on June 14, 2011, 02:58:00 am
This is absolutely fantastic. I can ditch TV cable and watch EEVBlog and your channel all day long :)

 ;D

That's great! EEVBlog was the reason why we started TheSignalPath! We have lots of topics planned for the future, it just takes so long to produce these videos. Feel free to join our forum and leave us a message or recommendations.
Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: thmjpr on June 14, 2011, 04:52:57 am
Very nice video.


I think there is a good explanation for the neon bulb flashing here:
http://www.ibiblio.org/kuphaldt/electricCircuits/Semi/SEMI_7.html (http://www.ibiblio.org/kuphaldt/electricCircuits/Semi/SEMI_7.html#xtocid154811)
http://www.thesuperclick.com/2/NEON_LAMP/default.aspx (http://www.thesuperclick.com/2/NEON_LAMP/default.aspx)

Once struck, the turn off voltage is lower, which means it will stay lit for a bit (hysteresis):
(http://i.imgur.com/jtLbw.gif)

The flashing seems a bit erratic though, not sure how to explain that.
Maybe someone can calculate the frequency (assume neon strike voltage = 200V?).

edit: you should add a donate link on your website when you have the time :)
Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: Hugoneus on June 14, 2011, 03:05:13 pm
Thank you! I too agree that the answer lies in the property of the neon tube. Its "strike" voltage and its steady state lit voltage are different causing a hysteresis. The smaller capacitor becomes discharged to below the "on" voltage and it turns off until the smaller capacitor charges to above the "strike" voltage. Since that 4.7MOhm resistor is in the middle, it can't stay on continually.

PS: I am also from Canada, but now live in the US. Thank you for your suggestions, can you kindly post your answer on the TheSignalPath forum as well?

Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: djcrunkmix on June 14, 2011, 04:21:01 pm
Are you the owner of TheSignalPath?
Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: Hugoneus on June 14, 2011, 04:22:32 pm
Quote from: djcrunkmix on June 14, 2011, 04:21:01 pm
Are you the owner of TheSignalPath?


Yes, I am one of the main two owners.
Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: thmjpr on June 15, 2011, 02:54:51 am
Quote from: Hugoneus on June 14, 2011, 03:05:13 pm
Thank you! I too agree that the answer lies in the property of the neon tube. Its "strike" voltage and its steady state lit voltage are different causing a hysteresis. The smaller capacitor becomes discharged to below the "on" voltage and it turns off until the smaller capacitor charges to above the "strike" voltage. Since that 4.7MOhm resistor is in the middle, it can't stay on continually.

PS: I am also from Canada, but now live in the US. Thank you for your suggestions, can you kindly post your answer on the TheSignalPath forum as well?

I posted in the appropriate thread: http://thesignalpath.com/forum/index.php?topic=10.0 (http://thesignalpath.com/forum/index.php?topic=10.0)

I included my (failed) ltspice attempt as well.
Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: ivan747 on June 19, 2011, 03:58:44 pm
Quote from: djcrunkmix on June 14, 2011, 02:58:00 am
This is absolutely fantastic. I can ditch TV cable and watch EEVBlog and your channel all day long :)

 ;D

That's exactly what I've been doing since I discovered how to subscribe to channels.
Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: Alex on June 19, 2011, 08:54:14 pm
Very nice video indeed! More 'how stuff works' type videos would be great, I think they fill a gap. I have 6 of those exact tubes next to my bed in a clock, they really are beautiful, especially in the LCD era.

Quote from: thmjpr on June 14, 2011, 04:52:57 am
Once struck, the turn off voltage is lower, which means it will stay lit for a bit (hysteresis):

I am working on a nixie project at the moment and have this fresh in my head. If you want to further read up on this (and the operation of cold cathode tubes), you can look up the terms 'maintaining potential' during 'normal glow' operation.

Alex
Title: Re: Camera Flash Circuit and Nixie Tube Tutorial
Post by: faz_8@hotmail.com on November 24, 2016, 06:39:20 pm
Hi,
Any body knows about video streamer card? I have attached the picture.



Quote from: ivan747 on June 19, 2011, 03:58:44 pm
Quote from: djcrunkmix on June 14, 2011, 02:58:00 am
This is absolutely fantastic. I can ditch TV cable and watch EEVBlog and your channel all day long :)

 ;D

That's exactly what I've been doing since I discovered how to subscribe to channels.