Menticol
Active Member
Hello!
There is a previous post about building an oscilloscope using a TV set. Nigel said "Buy a scope! - there's no decent, reasonably priced, way to use a TV as a scope."
Maybe that's true for a serious electronics designer or technician, or a hobbyist on a first world country where used oscilloscopes are cheap as dirt. But here in my country, used oscilloscopes are very expensive (earning 600.000 COP is hard as earning 600 USD on the USA!). Such amount of money to measure a couple of signals on noob projects... is definitely a waste!
I have two options, TV based and PC based oscilloscope (AD converter via parallel port). I'll try the TV version first
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I've applied the classical procedure: disconnecting the vertical coil, but I didn't inverted the yoke as the websites say: I took some measurements instead
Maximum Vertical Deflection: + 4,6 V
Minimum Vertical Deflection: - 4,6 V
Coil resistance: 14,7 ohm
I have some questions, if anyone can help:
Question 1) What signal amplifier would be decent for the Job? I've found (and attached here) an schematic that uses a crappy 741 OP AMP. As Audiguru says, it's a lousy old amp!
Now the horizontal coil. I understand that a Sawtooth generator is required.
Maximum left deflection: XX V
Maximum right deflection: XX V (Tonight I'll fill the missing values)
Coil Resistance: 4,65 ohm
Question 2) Can a 555-based circuit do the job?
Question 3) How can the circuit be synchronized* with the vertical signal like the "Trigger" on a real oscilloscope?). I've read something about messing with the TV's V-Sync, but information was incomplete.
* Sorry, I don't know the real term.
Thank you very much for your help!
_______________________________________________________________________________________________
EDIT: The schematics are in Spanish. I've attached them just as an example of what I found. First one is the horizontal driver, second one is the vertical amplifier, third one is the ramp generator. The original author is: https://www.yoreparo.com/foros/diseno_electronico/125029_0.html#461862
There is a previous post about building an oscilloscope using a TV set. Nigel said "Buy a scope! - there's no decent, reasonably priced, way to use a TV as a scope."
Maybe that's true for a serious electronics designer or technician, or a hobbyist on a first world country where used oscilloscopes are cheap as dirt. But here in my country, used oscilloscopes are very expensive (earning 600.000 COP is hard as earning 600 USD on the USA!). Such amount of money to measure a couple of signals on noob projects... is definitely a waste!
I have two options, TV based and PC based oscilloscope (AD converter via parallel port). I'll try the TV version first
____________________________________________
I've applied the classical procedure: disconnecting the vertical coil, but I didn't inverted the yoke as the websites say: I took some measurements instead
Maximum Vertical Deflection: + 4,6 V
Minimum Vertical Deflection: - 4,6 V
Coil resistance: 14,7 ohm
I have some questions, if anyone can help:
Question 1) What signal amplifier would be decent for the Job? I've found (and attached here) an schematic that uses a crappy 741 OP AMP. As Audiguru says, it's a lousy old amp!
Now the horizontal coil. I understand that a Sawtooth generator is required.
Maximum left deflection: XX V
Maximum right deflection: XX V (Tonight I'll fill the missing values)
Coil Resistance: 4,65 ohm
Question 2) Can a 555-based circuit do the job?
Question 3) How can the circuit be synchronized* with the vertical signal like the "Trigger" on a real oscilloscope?). I've read something about messing with the TV's V-Sync, but information was incomplete.
* Sorry, I don't know the real term.
Thank you very much for your help!
_______________________________________________________________________________________________
EDIT: The schematics are in Spanish. I've attached them just as an example of what I found. First one is the horizontal driver, second one is the vertical amplifier, third one is the ramp generator. The original author is: https://www.yoreparo.com/foros/diseno_electronico/125029_0.html#461862
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