Quote from: exleo on Sep 01, 2010, 09:26 am
ooooo even many a professional film or television prop has it's roots set deep inside a Poundland or 99p shop....all hail to the great bargain basement

Yeah, I remember watching the video tour of Matt Smith's TARDIS interior and the guy on the video points out that the hexagonal things in the walls are plant pots from a garden centre! I just have images of the prob builder driving his wife mad every time they go to somewhere like B&Q or a garden centre and him shouting "That's perfect for the TARDIS walls!" when she's trying to find something for the house.

This is probably one of the reasons why, if I'm on a mission to find TARDIS bits or anything similar I have to go alone.... 

I have my 1/2 scale Police Box and my biggest issue for my personal completion (aside from having the right handles and jam-jar) is that I want a flashing light.  More specifically (after watching some Doctor Who episodes), I "would like to have" a light that fades in and out at 1.5 second intervals.

I tried figuring this out 3 years ago and 7 years ago, but with little success (and I got busy and have not looked around again until now).

I have looked at diagrams for 555 Timer circuit, but I don't know enough about electronics to diagram the circuit, get the parts and solder what I need together (basically the whole kit-and-caboodle).  Many diagrams I have seen deal with "blinking" which is not what I want.  And most of these diagrams use LED.  Unfortunately, LED most likely will not succeed at dimming unless you rapidly change the voltage up and down to give the illusion of dimming on and off.

Aaannyway, anybody have any ideas how?

There's a couple of things you can try.  1) Car indicator or 2) a light bulb flasher.  The second typically is some you can get a Radio Shack and it allows you to plug it into the power cable to the light and then into the wall or can be screwed directly into the socket (depending on model).  Some may have a set rate or a variable rate control.  See this.
http://www.nfss.com/hfholicooufl.html
Bill "the Doctor" Rudloff

Hmmm.  Car Indicator - now that is a new one.  I never thought of that.

On the Radio Shack flasher, there does not appear to be any specifications on the site.  Might have to go into the store and see if I can get details on the back of the packaging.

I'll check those 2 out though.

Jason, check out page 2 of my build thread called [ref topic=537]Kevin's 3/4 NST build[/ref]

There you will find a circuit that does exactly what you want.  It was designed to drive large LUXEON LEDs, but those can be omitted.  There are small LEDs that are mounted on the circuit board, and those could easily be re-located inside the lamp of your 1/2 scale build.  

Quote from: ivorydrops on Oct 23, 2010, 04:01 pm
I have my 1/2 scale Police Box and my biggest issue for my personal completion ....... is that I want a flashing light.  More specifically .... I "would like to have" a light that fades in and out at 1.5 second intervals.
.....
I have looked at diagrams for 555 Timer circuit, but I don't know enough about electronics to diagram the circuit, get the parts and solder what I need together ... Many diagrams I have seen deal with "blinking" which is not what I want.  And most of these diagrams use LED.  Unfortunately, LED most likely will not succeed at dimming unless you rapidly change the voltage up and down to give the illusion of dimming on and off.

Aaannyway, anybody have any ideas how?

I believe that is doing exactly what I want.  Ugh, the work on building the circuit is going to be painful.  And he is doing what I anticipated -- using multiple LEDs.

I like the idea that I did everything very inexpensive on my box at that time.  Coughing up over $60 for the light when the total supplies for my box was around $150 (minus certain hardware purchases) makes the circuit board hard to justify unless I use it for my future full-scale one.

Need to think about it despite the fact that it is exactly what I want.

Quote from: Theta Sigma on Oct 24, 2010, 01:37 am
Jason, check out page 2 of my build thread called [ref topic=537]Kevin's 3/4 NST build[/ref]

There you will find a circuit that does exactly what you want.  It was designed to drive large LUXEON LEDs, but those can be omitted.  There are small LEDs that are mounted on the circuit board, and those could easily be re-located inside the lamp of your 1/2 scale build.  

Quote from: ivorydrops on Oct 24, 2010, 05:56 am
I like the idea that I did everything very inexpensive on my box at that time.  Coughing up over $60 for the light when the total supplies for my box was around $150 (minus certain hardware purchases) makes the circuit board hard to justify unless I use it for my future full-scale one.

Jason, about half of that $60 is taken up by the large LUXEON LEDs.  Using 4 of them for a 1/2 scale build would probably be too much.  You could always reduce the number of LUXEON LEDs to 1, or substitute a cheaper, less powerful LED.  If you do this, the resistance value of the 5W resistor would need to change to provide a greater voltage drop to protect the LEDs in a modifed circuit.  If you want, I could modify the circuit design to use whatever LED you want to use.  You'd just have to send me the specs on your chosen LED.

Here's a very "quick and dirty" way of doing flashing lights;

Burn a CD of the TARDIS take-off noise and get a cheap CD walkman type player. Snip off the headphones and strip the wires back, underneath the main black insulation you'll have an uninsulated earth wire and two insulated wires (usually red and white). Connect the negative side of the LEDs to the uninsulated earth wire and the positive side to the two insulated wires.

Crank up the volume of the CD player up and press play - the LEDs will light up in time to the sound output which in this case is the TARDIS take off noise!

That is quick and dirty.  I always thought there was a way to do it in that manner, but I never literally tried doing THAT.  I might have to try that out of humor.

I've done this with a car stereo! If I get a chance I'll upload a video of this later.

Car stereos have the advantage that they have four channels so you can have the sound too. Also you can adjust the fade and balance so you can "fine tune" the lights and sound accordingly.

Quote from: Theta Sigma on Oct 24, 2010, 01:44 pm
Jason, about half of that $60 is taken up by the large LUXEON LEDs.  Using 4 of them for a 1/2 scale build would probably be too much.  You could always reduce the number of LUXEON LEDs to 1, or substitute a cheaper, less powerful LED.  If you do this, the resistance value of the 5W resistor would need to change to provide a greater voltage drop to protect the LEDs in a modifed circuit.  If you want, I could modify the circuit design to use whatever LED you want to use.  You'd just have to send me the specs on your chosen LED.

I don't mind doing one LUXEON on the circuit, but you will have to tell me how to modify the circuitry on your specifications.  Though, I will admit that I like the fact that I can get all the parts locally and not have to buy one LUXEON piece and pay outrageous shipping for one piece.  Also, futureelectronics.com appears to want to sell lots of 100 though they mention to call for single item purchase.  I think the $8 you mention in your price list is what you got when you called for price per single item.  What was shipping?

Alternatively, I could use any of the ones below.  This might make the difference of shipping from getting at futureelectronics.com and having instance bliss on acquiring the parts.  I am sure other readers would appreciate that option.

Anyway, here are other choices I found, but personally I am not partial to these specifically if you happen to notice a better choice.

5mm High-Brightness White LED ($2 at Radio Shack)
# High visibility, 5mm Round T-1 3/4
# Intensity 7000mcd (typical);viewing angle 30°
# FW current 25mA; FW supply 3.3 (typical), 3.6V (maximum)
# RoHS compliant

OR

5mm White LED ($5 at Radio Shack)
# Typical Voltage: 3.2V
# Typical MCD: 1100
# 20mA (max)
# Viewing angle: 50°

Quote from: wayne venomous on Oct 24, 2010, 05:55 pm
I've done this with a car stereo! If I get a chance I'll upload a video of this later.

Car stereos have the advantage that they have four channels so you can have the sound too. Also you can adjust the fade and balance so you can "fine tune" the lights and sound accordingly.

Does that work with any LED or regular small bulb -- like a nightlight in the bathroom?

Though, I do like the idea that the sound can be played and will be in sync with the light.

Just curious because so many people are concerned with having the light flash in sync with the sound, but weren't there several stories, especially in the Classic episodes, where the TARDIS light flashed either slower, or in more cases faster than the sound?

Dino.

Quote from: galacticprobe on Oct 24, 2010, 06:59 pm
Just curious because so many people are concerned with having the light flash in sync with the sound, but weren't there several stories, especially in the Classic episodes, where the TARDIS light flashed either slower, or in more cases faster than the sound?

Yes, there were SEVERAL.  VERY inconsistent.  Chuck it up to the discontinuity of Doctor Who.

Basically, what it boils down to (at least for me) is ... what looks right.

To me, a 1.5 second fade in (.75) and out (.75) interval looks right and I seem to recall seeing this pattern more often than others.  I believe I got this calculation from "Invasion of Time" when the TARDIS first lands on Gallifrey.  That flashing sequence and sound just felt right to me.

Quote from: ivorydrops on Oct 24, 2010, 06:26 pm
Anyway, here are other choices I found, but personally I am not partial to these specifically if you happen to notice a better choice.

5mm High-Brightness White LED ($2 at Radio Shack)
# High visibility, 5mm Round T-1 3/4
# Intensity 7000mcd (typical);viewing angle 30°
# FW current 25mA; FW supply 3.3 (typical), 3.6V (maximum)
# RoHS compliant

OR

5mm White LED ($5 at Radio Shack)
# Typical Voltage: 3.2V
# Typical MCD: 1100
# 20mA (max)
# Viewing angle: 50°

Here's what I use for white LEDs - Poundland (UK equivalent of 99 Cents stores or similar)

Always handy to experiment with:

Doesn't have to be camping lights either, there's always stuff using white LEDs such as flashlights, bicycle lights etc etc. And if you blow them up well they weren't expensive!
These ended up being a licence plate light:

Quote from: ivorydrops on Oct 24, 2010, 06:28 pm

Quote from: wayne venomous on Oct 24, 2010, 05:55 pm
I've done this with a car stereo! If I get a chance I'll upload a video of this later.

Car stereos have the advantage that they have four channels so you can have the sound too. Also you can adjust the fade and balance so you can "fine tune" the lights and sound accordingly.

Does that work with any LED or regular small bulb -- like a nightlight in the bathroom?

Though, I do like the idea that the sound can be played and will be in sync with the light.

Any standard LED should work, I wouldn't try a Luxeon star type though.