Self built JK Flip-Flop

Thread Starter

fluffyninja

Joined Mar 2, 2012
9
Good - did you download the 74hc and cd4000 libraries?
OK, keep in mind that under the "Edit Simulation Command", the "Stop Time" is what determines how long that the simulation runs; the default unit of time is seconds - so, 60 seconds is 1 minute; 3600 seconds is 1 hour, etc.

http://www.Mouser.com, http://www.Digikey.com, http://www.avnetexpress.com are authorized distributors for a number of electronic component manufacturers, and have very good to excellent track records. You should stick to authorized distributors at least until you get fairly well experienced; there are lots of counterfeit components out there nowadays.

You might consider using http://www.findchips.com to discover who has components available and what the prices were at the time the inventory was checked. It's not 100% accurate, but it can help you find stuff quickly.
I haven't tried the libraries out, yet. Thus far my simulation has been working well using Td=15 and Td=10 on my gates.

Ah-hah! I assumed since it said "1s" I could put "10h" for 10 hours. Silly of me, problem solved! I have it set to 3600 seconds, now. The simulation took around 10 seconds to fully load.

I'll check more into the libraries soon, I promise.

This forum makes me feel like a kid in a candy store with an unlimited budget. So much fun stuff to learn about and play with!
 

SgtWookie

Joined Jul 17, 2007
22,230
I'd like to get a big old bag of logic ICs to start, from what I've seen they aren't too terribly expensive. I may even cheat and use some JKs without NANDing them together myself, as that'll make troubleshooting much easier on my poor brain.
The cost adds up quite quickly. You might find the cost of 74hc IC's at somewhere in the neighborhood of $0.30 to $1.00 each.

Keep in mind that 74xx and 4000 series ICs are basically obsolete technology; everything is going to microcontrollers nowadays. There are some 74xx series ICs that are still useful for various things, but if parts count starts climbing, microcontrollers are the way to go. Logic ICs are useful for learning, but don't stock up too much on them.

Here's a list of stuff I need as I understand it currently:

Breadboard
Breadboards are useful for low-speed circuits. You may wish to get a few of them. A clock will tend to have a fair number of ICs that you'll have to wire up.

20x JK flip-flops
Keep in mind that an individual IC can have multiple gates in it. JK and D-type F/F's usually have two or more per package. D-type F/F's are very useful as /2 circuits; just wire the Q\ output to the D input, and clock the IC. The Q output will be 1/2 the clock frequency, and the Q\ output will be complementary to the Q output.
LEDs can be obtained pretty cheaply. You'll also need to limit the current through the LEDs using resistors. Additionally, you really can't use a TTL or CMOS output to both drive an LED, AND as a logic signal; that will call for transistor drivers. You should also get some NPN transistors and PNP transistors. 2n3904 & 2N3906, 2N4401 & 2n4403, 2N2222 & 2n2907 are all common transistors that can be used for drivers. You'll also need 1k resistors for the transistor bases, and ~470 Ohm resistors to limit the LED current.
5V power supply
You may wish to make your own bench supply from a surplus ATX or ATXplus12 form factor PC supply. Google "ATX bench supply" for lots of ideas.
12x AND gates (probably less, but I understand they're fairly cheap).
There are four 2-input AND gates per IC package.
You should have some NAND and some NOR IC's on hand; using just NAND gates or NOR gates, you can build any other logic function. Google "NAND logic" and "NOR logic".

Timing source (555 would work fine for proof of concept, and they're super cheap.)
Sure, why not?

Here's what I already have:
2x Butane soldering irons
Not too useful. A temp-controlled electric iron is much more useful. A butane iron will always seem to run out of gas at the wrong moment.
Acid-core solder
Acid core solder is absolutely useless for electronics. Don't use it.
You need either plain or rosin-core solder. 63/37 is best. 60/40 is also good. 50/50 can be used, but it is too easy to make cold solder joints with it.
You need rosin flux. If your parts/board/solder/iron are clean & bright, you really should not need flux. Finger oils will contaminate your work and make soldering difficult. Clean parts with 90% or better isopropyl alcohol and a soft nylon brush (acid brushes work very well). 3M(tm) Scotchbrite(tm) pads work great for removing corrosion from component leads and circuit boards.

Limited soldering experience. I've made a clock before, but it was a kit with diagrams.
Practice makes perfect. Nobody is born making perfect solder joints. My early soldering efforts looked like miniature slag heaps; something a volcano vomited out. :rolleyes: It takes practice to get good at it.

Cleanliness counts a great deal; even a small amount of contamination or corrosion will make a decent joint very difficult or impossible. The iron needs to be clean, tinned, and at just the right temperature.

If the iron is too cold, you risk burning up the components, as you'll have to have the iron on the leads too long trying to get the solder to melt. If it's too hot, you risk lifting pads on the board, and the iron will quickly oxidize.

There are a number of posts with soldering tips. You'd be well-served to get some boards to just practice on, and solder on some surplus components. Places like Electronics Goldmine sell surplus stuff cheaply; they work fine for things like this.

Resist the temptation to over-buy components; you can quickly wind up with a huge amount of stuff that becomes a chore to organize, and takes up a lot of space. If you don't have it well-organized, you won't be able to find it - so it will take up space while being useless.
 

SgtWookie

Joined Jul 17, 2007
22,230
By the way, what is that you are holding in your avatar? Looks sort of like an M72 LAW like was used many years ago.

And is that a rack of M4's behind you?
 

Thread Starter

fluffyninja

Joined Mar 2, 2012
9
By the way, what is that you are holding in your avatar? Looks sort of like an M72 LAW like was used many years ago.

And is that a rack of M4's behind you?
It's commonly known as an AT-4 (Anti-Tank, 84mm. AT-4 is a play on words). It's officially know as the M72's hotshot younger brother, the M136 LAW.

And you're half right, it's actually TWO racks of M4s.
 

SgtWookie

Joined Jul 17, 2007
22,230
Thanks,
I was wondering what you'd be doing with a LAW; they've been obsolete for many years. I couldn't remember the AT-4 designation; they came along after my active duty time - and I was a Winger anyways.

I couldn't quite figure out the configuration of the rifle racks behind you; since I wasn't in a ground combat MOS, the only time I'd seen rifle racks in a squadbay was during boot camp - and ours were single layer with M16A1's.
 
Top