Yesterday I was a little bored and I was staring to a box full of quartz cristals. I was wondering what frequency was, especially a very old one with russian marks on it. I know from an elder that the number on the Russian cristal is not the frequency but some sort of code. Stupid, eh?
After I contemplate various possibilities of transistor oscillators, I came up with a simple, reliable and versatile TTL configuration, "a classic" to say it simple.
It's a 74LS00 oscillator in series configuration, the schematics is pretty self explanatory.
Now I cand measure with precision the exact frequency of my 38.9 MHz crystals which, by the way, are overtone! I will make nice filters for 12.95 MHz on long winter days!
Without a quartz crystal, it self-oscillate around 50 MHz with a very nice sinus wave!
The signals are from pin 6 and pin 11:
Self oscillation>
With a crystal:
Abonați-vă la:
Postare comentarii (Atom)
Most viewed posts in last 30 days
-
Kenwood Programing Software FIRMWARE: KDS-100 504XXXXX 4A46 PTT ID Display feature 176.86 KB CURRENT 401XXXXX F7FC Corrects lock up whe...
-
Icom IC-7300 wide band modification by PA2DB: Remove bottom and find the diode matrix (near big chip) Open RX 0.030-74.8Mhz (REMOVE D...
-
Icom programming Software GM-110SC rev.1.2. ex1725. IC-3FX 245MHZ THAILAND CB HANDY RADIO, EX2020 REV 1.0. IC-3FGX 80 CHANNELS 245MHZ THAILA...
2 comentarii:
Say me please, Did you try to reduce glitch ?
Nope! I was trying to measure the crystal frequency not to use this oscillator for transmitters so I was not interested in a pure wave form.
Trimiteți un comentariu