#555 timer

[solstacoded]

ne555 timer concept (i don't know how to draw)

[futurebird]

Some kind of arachnid…

Can I get help with an id?

[arduino-diy]

Transformers PCB BADGE

It's been a while, the Autobots have appeared on the silver screen. Finally they are returning to the big screen in their upcoming Transformers movie "Rise of the Beasts".

This inspired me in making a PCB Badge to complement my enthusiasm and love towards the Autobots.

In this tutorial, I am going to show you guys how to design this "Transformers PCB Badge" and how to solder the components to it.

[wired-weirdness]

Sometimes it’s fun to waste parts in the desire to learn how something works. I haven't ever connected more than one shift register together before. I went to my parts bins but was defeated to find I only had one shift register so, the bench testing fun will have to wait. Below is a simple circuit using two 555 timers as a clock and "data" input. In real life I was going to use one of my favorites the LM556 a dual 555 time on a single integrated circuit (IC). As for the shift register the IC of choice was the 74HC595.

Once built in the simulator I became inspired to try and out the LEDs in a fashion to use as one of those 3X3X3 LED matrixes. Make it like random-ish static cube, I'll have to play with the design a little more.

[quartz-components]

NE556N Dual Timer IC

NE556 has two Timers inside a single package which reduces the form factor and complexity of the system. Functionality and pin description wise both 555 and 556 are identical. Learn more about it: https://components101.com/ics/ne556n-dual-timer-pinout-datasheet  

[insectoid5]

@blunaowl replied to your post “I got myself a little toy at the bookstore this afternoon...”:

SHOW ME THE FADING TARDIS

Ask and you shall receive!  This video and the photos are new, taken with my Canon Elph 170, rather than the crummy ones I took with my old iPod touch 4 way back in 2013.  The text below, describing how I did it, is mostly derived from the Facebook post I wrote.  I’ll put that below a read more, since it’s kind of technical electronics babble and may not be for everyone. 😅

Sherman, set the WABAC machine to summer of 2013.  It was late July, and my mom and I (at the encouragement of her friend) had started watching the new Doctor Who, and we were over a season into it.  On an outing, we just happened to stop at a B&N bookstore, where I saw this cute light up TARDIS, and happily bought it.  It’s about 3″ tall, including the light, and 1.5″ on a side:

This is with the white LED, of course; the blue one looked MUCH more out of place.

I was initially disappointed to discover that its illumination was a) with a blue LED, and b) static, either on or off with the switch on the bottom.  So I opened it up and, finding a sufficient amount of extra space inside, started planning a hack.

I didn’t actually get around to serious planning until a month later, when I figured out how I might build an LED “fading” circuit with minimal component and power requirements.  So I did a Google search for circuit ideas, and what I came up with was this simple 555 timer circuit:

Yes, I drew this.  One of the perks of growing up with an EE is learning electronics and schematic drawing.

Besides the ever-useful 555 chip, only a few other components were needed: a capacitor to store charge (which helps create the “fading” effect); a potentiometer (variable resistor), to adjust the frequency (the speed of the fading); a general-purpose transistor; and another resistor for the LED (the blue LED came with one connected near the switch, I think, but I used a different value).  Finding all of these parts, except one, didn’t even require leaving the house (yet another perk of living with an EE), but I did have to find a 3 mm white LED.  (At Fry's, probably.)  This is the finished circuit, which I put together that Labor Day weekend:

The part number is vague, but the chip is definitely a Philips/Signetics NE555.  It was a numbering scheme often used by Hewlett-Packard for outsourced parts, so this was probably among the old parts salvaged by my dad from his work.

Assembling and soldering the circuit took me several hours, mostly because I am a perfectionist was being careful to not make mistakes.  Then there was the difficulties I had with the battery—or rather, batteries.  The toy TARDIS came with a single CR1632 3-volt lithium cell, with a metal contact on the side for the (+) and on the bottom for the (-).  To operate the 555 and LED, I needed at least 5 volts; the simplest solution to this was to use two CR1616 3-volt cells in series.  The problem was that the tab on the side (for the + terminal) would contact both batteries, making a parallel circuit.  So, I had to fabricate a new terminal that goes over the top of the cells, without touching the sides:

It looks crude, but it works.  Someone on FB suggested that I add a sound chip, but I wouldn't know what kind, and don't know if there's enough juice in 2 coin cells to run it... 😅

[schematicdesigns]

Safety Tail Light

When vehicles were first invented, the only light it has was for forward vision. At that time, there are few vehicles, so communications to other vehicles are not that important. The rapid increase of vehicles raises the need of a way of communicating other vehicles. Thus, the lighting system of ...

[wired-weirdness]

Off-delay 555 circuit (negative trigger)

I needed a way to have a relay “ride” through a starting sequence on a vehicle. Annoyingly there was no steady ignition sources so it was to the market on off-delay timers so the circuit can ride through the start while still turning off when the circuit is truly off. There is one constant source and a source that goes negative during starting.

With the vehicle off the circuit is as above. The 555 is timed out, the seal in and timer mosfet is off and the trigger mosfet is sealed.

When the ignition is turned on the seal in mosfet is active holding the relay on. ( this can be done with bjt’s as that is what was originally in the circuit)

During starting the trigger circuit goes negative activating the 555 to hold the relay through the start cycle through the timer mosfet.

Then the vehicle is running and the trigger circuit holds the relay high till the vehicle is turned off. Then the circuit returns to a off state after the set time.

Note: The trigger mosfet can be removed and the 100k ohm resistor moved onto the trigger circuit.