Oscilloscope
From Eric
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The datasheet can be found here : http://www.ges.cz/sheets/8/8sj31jv2.pdf | The datasheet can be found here : http://www.ges.cz/sheets/8/8sj31jv2.pdf | ||
+ | = My setup = | ||
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+ | For the generation of the high voltages, I'll use a 220V/220x2+6.3Vx2 ransformer ([https://fr.aliexpress.com/item/32999845562.html?spm=a2g0s.9042311.0.0.305b6c3795fiDS bought on AliExpress]): | ||
+ | [[File:transformer_for_tube.jpg|400px|thumb|none]] | ||
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+ | I'll use a Greinacher voltage doubler to generate the -600V. The +220V voltage will be obtained by half-rectifying the transformer's secondary output. | ||
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+ | The Greinacher circuit: | ||
+ | [[File:greinacher.jpg|400px|thumb|none]] | ||
= Other schematics = | = Other schematics = |
Revision as of 16:17, 9 January 2021
Contents |
General information about CRT tubes
Some explanations about the functioning of a CRT:
- http://www.cfp-radio.com/realisations/rea75/tv2pouces-01.html
- http://speakyssb.blogspot.com/2016/08/5lo38i-crt-test.html (5LO38I tube)
- https://www.electrical4u.com/cathode-ray-oscilloscope-cro/
- https://www.circuitstoday.com/crt-cathode-ray-tube
- https://www.aplustopper.com/cathode-ray-oscilloscope-construction-working/
General diagram
The most popular schematic, from Elextronixandmore, using a Hammond transformer. A kit can be bought at Catahoula Technologies. The schematic and the BOM are here.
Another one solid-state scope from Electronixandmore, without isolation. The voltages are the following:
HV 350V Anode Cap X1/X2/Y1/Y2 280V Deflection plates A2 270V Anode 2 A1 -310V Anode 1 K -665V Cathode G1 -675V Control Grid
Those values are fine for a 3BP1 tube.
The tubes
5LO38I russian tube
I have bought a russian 5LO38I tube on ebay.
The tube is delivered with a russian notice. Hopefully, someone has provided a german translation translation:
This gives:
- Filament voltage: 6.3V, 600mA +/- 10% (5.7 to 6.9V)
- Anode voltage: 1000V (500V to 1100V)
- Deflection:
- On X: 0.09 to 0.14 mm/V
- On Y: 0.11 to 0.16 mm/V
- Focus voltage : 138V to 300V (<550V)
- Cathode voltage: (-125V to 0V)
- G1 voltage: -30V to 90V (-125V to 0V)
- Voltage between "ablenkplatten" and anode: (-660V to 660V)
You can find several applications of the 5LO38I:
- http://danyk.cz/osc_en.html
- http://speakyssb.blogspot.com/2016/08/5lo38i-crt-test.html
- http://www.emartinka.cz/index.asp?IDKategorie=9&IDClanku=18&Akce=clanek
- http://www.labguysworld.com/ES_CRT_DEFLECTION.htm
- http://users.triera.net/zupanbra/osciloskop/Mali_osciloskop.html
- http://www.webx.dk/oz2cpu/clock-scope/scope.htm
Several schematics to generate the high-voltage power supplies:
Chinese 8SJ31J tube
See Aliexpress (8SJ31 from GuangYi store (Aliexpress).
The datasheet can be found here : http://www.ges.cz/sheets/8/8sj31jv2.pdf
My setup
For the generation of the high voltages, I'll use a 220V/220x2+6.3Vx2 ransformer (bought on AliExpress):
I'll use a Greinacher voltage doubler to generate the -600V. The +220V voltage will be obtained by half-rectifying the transformer's secondary output.
The Greinacher circuit:
Other schematics
- https://www.webx.dk/oz2cpu/clock-scope/scope.htm
- http://www.jogis-roehrenbude.de/Leserbriefe/Scope-Clock/Scope-Clock.htm
- https://web.jfet.org/vclk/
- http://www.catahoulatech.com/index.php?product=KIT-0001|PCB
- http://www.sgitheach.org.uk/scope2.html
- http://ludens.cl/Electron/scope/scope.html
- https://www.eevblog.com/forum/projects/oscilloscope-under-construction/
- https://www.eevblog.com/forum/projects/2-inch-video-monitor/
Other topics
Oscilloscope music:
- https://oscilloscopemusic.com/software.php (a software to generate pictures using X-X modulation))
See also: