What means
A resistor placed horizontally in a text-mode circuit sketch.
A resistor limits current in a circuit. On Sharp MZ computers, the Japanese primary character set was a built-in table of display symbols; E3 was this character's machine code. The MZ-80K appeared in 1978.
Unicode's proposal groups it with schematic parts meant to join light box-drawing characters. Text glyphs could show components and their wires; Unicode preserves this one for conversion and emulation.
Don't confuse it with
4Combination ideas
1Suggested circuit sketch: one resistor between two horizontal wire runs.
Questions people ask
1Why does show as a box on some devices?
Because that device's fonts have no glyph for it. The character is still correct and still copies correctly — the box is a missing glyph, not a broken character.
How to type
Windows (Word)
Alt+XType 1CC09, then Alt+X to get .
Windows
Win+Rrun charmap for the full table, or use the emoji picker's Ω symbols tab (Win + .).
macOS
Control+Command+SpaceOpen the character viewer and search “horizontal resistor segment”.
Linux
Ctrl+Shift+UType 1cc09, then Enter or Space.
HTML
𜰉CSS
\1CC09HTML
Use `𜰉` in HTML source; the Sharp MZ's E3 display code is not Unicode input.
JavaScript
In a modern JavaScript string, write the escape `\u{1CC09}`.
Codes and encoding1 code points
HTML decimal
𜰉
HTML hex
𜰉
CSS content
content: "\1CC09";
Each escape is closed by the next backslash; a trailing space is needed before a literal hex digit.
URL encoded
%F0%9C%B0%89
1
On screen
1
Code points
2
JS .length
4
UTF-8 bytes
A visible symbol can contain several code points. JS .length counts UTF-16 units; UTF-8 counts bytes.