How To Make A Crystal Oscillator Circuit  - Page 1
Forum section: electronics / beginners

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: November 21, 2015, 07:06:26 pm
content: Hello i tackled a digital clock project where i faced some minor issues but i got really stuck at the frequency input.I want to create a quartz crystal circuit but i can't find a schematic or a guide to complete the damn thing...I found a few schematics that ill post bellow but am not sure that they will work or be accurate also i found some circuits where transistors are used but i was not sure if they will work at 5v or i will need an amp circuit to go on the output of the oscillator.anyway some help from real people would be nice since google has confused the crap out of me ...Thank you in advance!!!youtube video about crystal tester

author: edavid
author_rank: Super Contributor
timestamp: November 21, 2015, 07:15:22 pm
content: What is the frequency of your crystal?How are you building your clock? Discrete logic, microcontroller, ??

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: November 21, 2015, 07:20:43 pm
content: i would like to use a 4.096Mhz crystal so i can use a HEF4020B to get excactly 1Khz out because i want the clock to display milliseconds as well as date.I am using discrete logic for the construction of the clock.I am now starting to draw the schematic and got stuck at the frequency input.The rest i got it figured out and i hope this is the last problem i cant solve with a little research.

author: kerrsmith
author_rank: Regular Contributor
timestamp: November 21, 2015, 08:23:44 pm
content: If you need a few ideas about oscillators I really recommend watching some of the videos on radiofun232's Youtube channel.https://www.youtube.com/user/radiofun232He makes loads of different oscillators that can be used for many different applications and he explains what to do to get them working correctly.All his videos are really hands on and extremely interesting.

author: PA0PBZ
author_rank: Super Contributor
timestamp: November 21, 2015, 08:24:53 pm
content: Quote from: ChrisGreece52 on November 21, 2015, 07:20:43 pmA 4060 is also a 14 stage counter but it has a built-in oscillator, have a look at the datasheet.

author: Zero999
author_rank: Super Contributor
timestamp: November 21, 2015, 08:38:38 pm
content: In the circuit using gates, it's a good idea to add another gate to act as a buffer.Why not use the CD4060 which has the oscillator function built-in?http://ecee.colorado.edu/~ecen1400/references/CD4060BC.pdf

author: edavid
author_rank: Super Contributor
timestamp: November 21, 2015, 08:48:13 pm
content: Both of the schematics you show are the same circuit, using different ICs. It's a perfectly good oscillator, but you may need to reduce the value of R2 if your oscillator won't start. You will also need to add a trimmer capacitor so you can adjust the frequency to make your clock run on time.For the first circuit, note that you must use a 74HCU04, not a 74HC04.For the second circuit, note that a CD4060 is only guaranteed to work at 1.5MHz at 5V, so with a 4MHz crystal you would want to use a 74HC4060.

author: ChrisGreece52
author_rank: Frequent Contributor
timestamp: November 22, 2015, 08:48:42 pm
content: Thanks for your responsesI would like to go the single not gate but i am wasting 5 gates this way.The 74HC4060 idea could work nicely but i am not sure how the whole thing will come together i mean ... do i just get some caps , resistors , the IC and the crystal connect them like shown on the schematic in my second picture ?