Making a Binary Clock - Get Answers to Your DIY Questions

  • Thread starter Thread starter Tiger Blood
  • Start date Start date
  • Tags Tags
    Binary Clock
Click For Summary

Discussion Overview

The discussion revolves around building a binary clock, focusing on the necessary components, their specifications, and the challenges faced by a beginner in electronics. Participants share resources, clarify component functions, and suggest alternative approaches to the project.

Discussion Character

  • Exploratory
  • Technical explanation
  • Homework-related

Main Points Raised

  • One participant seeks clarification on how to find matching resistors for LEDs operating at 5 volts, noting the lack of specifications from the seller.
  • Another participant suggests that LEDs typically operate around 20 mA and mentions that using higher resistors can still yield sufficient brightness at lower currents.
  • Concerns are raised about the compatibility of SMD capacitors with breadboards, with a suggestion that they are unnecessary for the project if using an ATmega microcontroller with a built-in clock.
  • A participant recommends using an RTC DS3231 module for better accuracy instead of relying on a quartz crystal or the internal clock of the microcontroller.
  • Discussion includes the practicality of using a power supply in the 7.5-12 V range, with a suggestion to consider a standard USB charger instead.
  • Clarification is provided on the meaning of the "104" reference for capacitors, explaining it as a notation for capacitance value.
  • Some participants suggest that gaining experience through simpler projects before tackling the binary clock may be beneficial.

Areas of Agreement / Disagreement

Participants express differing opinions on the best approach to building the clock, with some advocating for simpler projects first while others emphasize the importance of understanding the components involved. No consensus is reached on the necessity of specific components or methods.

Contextual Notes

Participants mention various components and their specifications, but there are uncertainties regarding the exact requirements for the project. The discussion reflects a range of experience levels and varying approaches to learning electronics.

Who May Find This Useful

Individuals interested in DIY electronics, particularly beginners looking to build projects involving microcontrollers and LED displays.

Tiger Blood
Messages
50
Reaction score
11
I want to make a binary clock and I found a place with info of "how to" do it but since I'm total noob at electoronics I need some thing clearing some stuff

1st here's the link
http://www.instructables.com/id/LED-Binary-Clock-20/

So far I'm still in a process of obtaining the stuff, mostly from ebay, and on a list is this item:

matching resistors to apropiately drive your LEDs at 5 volts (you can calculate the value here).

But how do I find matching resistors? I know he put the calculator but the seller doesn't give any specs. I was thinking of buying these LEDs (yellow ones)
https://www.ebay.com/itm/100-500-10...ow-LED-Light-Bulb-Emitting-Diode/201863138713

Then he also lists: 220uf caps -- I've seen that some vary in price, you think these will do?
https://www.ebay.com/itm/10PCS-220UF-50V-105-C-Radial-Electrolytic-Capacitor-10-12mm/321424253165

On the 16Mhz crystal he says to get caps (22pf). Is this it:
https://www.ebay.com/itm/100pcs-22p-22pF-50V-0805-SMT-SMD-Capacitor-Cap-Brand-New/251169384898

He lists: 100nf caps (104) -- but what is "(104)"? would these do?
https://www.ebay.com/itm/1pf-100nf-...itor-Assorted-Kit-Assortment-Set/120982871681

Also I can't decide on breadboard. Do you think these one will do?
https://www.ebay.com/itm/10PCS-5x7cm-Bakelite-DIY-Prototype-Board-PCB-Universal-Breadboard-High-Quality/200979359499

or maybe one of these
https://www.ebay.com/itm/10PCS-Double-Side-Prototype-PCB-Bread-board-Tinned-Universal-FR4-2x8cm-9x15cm/263518832138

For power supply he said 7.5 to 12 volts out, do you think this one will do (EU 12V 2A)
https://www.ebay.com/itm/EU-US-Plug...wer-Supply-Converter-LED-Light-D/112142936428
 
Engineering news on Phys.org
Bunch of remarks, not intended to be complete:

These LEDs operate with currents around 20 mA, so you can easily calculate what minimum resistor is needed. You can use a bit higher resistors, as at 10 mA LEDs are often bright quite enough.

SMD (Surface-Mounted Device) capacitors are incompatible with breadboards, they have no legs and are intended to be soldered on the PCB surface directly. However, they are needed for quartz - which is redundant in this project. ATmega microcontrollers (μC) have built in clock (it will require changing so called fusebits, but it is not much more difficult than just programming the chip which you have to do).

Basing the clock on the quartz (or - even worse - internal generator) is asking for a poor accuracy. Much better is to buy RTC DS3231 (Real Time Clock) with additional battery (they are pretty cheap at 1 or 2 bucks, something like https://www.ebay.com/itm/DS3231-AT24C32-IIC-module-precision-Real-time-clock-module-memory-module-Arduino-/400503978923 - doesn't mean I endorse the seller) and connect it to the μC using I2C interface (even if it sounds complicated it is really trivial). My Nixie clock is made this way and it easily survives between DST changes, when I have to manually set it up even if it didn't drift by more than several seconds. Plus, such an RTC with its own battery is immune to the power outages.

I don't think it makes much sense to use a power supply in the 7.5-12 V range only to step the voltage down to 5 V with 7805, why not use any standard USB charger (may require opening the plug, but the voltage should be stable and the current well within the specs).

In general I would not start with just the μC, it will be better to buy Arduino, perhaps in a ready set with a breadboard and some other stuff, much less hassle and much easier to test your ideas and solutions. Once you play with it for a few days most of the things required to make the clock will be completely obvious.
 
  • Like
Likes   Reactions: Tiger Blood and berkeman
The 100 nF capacitor that has a reference of 104 is as follows: 104 means a 1, followed by a zero, and 4 more zeros in picofarads. 100000 pF which translates to 100 nF or .1 uF.
A capacitor that has a reference of 473 would be 47 nF (.047 uF).
 
  • Like
Likes   Reactions: Tiger Blood
OK, so I need a better tutorial.
 
More like you need some experience.
 
  • Like
Likes   Reactions: davenn
Tiger Blood said:
OK, so I need a better tutorial.
There is no need to know everything before making a start. It could help if you start with a cheap simple construction kit for flashing LEDs or similar. All circuits have a lot in common and you will get experience just from connecting stuff up. Aim at doing your clock project after some simpler stuff - something with just one function that you can concentrate on.
The spec sheets of logic families all have application sections with typical values for supporting components and also you can find thousands of circuits on google. For a source of suitable pictures, look at google images and dive in. Read read read. :smile:
 

Similar threads

  • Sticky
Getting Started With Computers and Programming
  • · Replies 13 ·
Replies
13
Views
8K