Mitsubishi C-3919: Difference between revisions
Adding derived TVL (600) based on 768 pixel horizontal resolution and 20 MHz video bandwidth (via update-page on MediaWiki MCP Server) |
Revising TVL derivation section with more accurate bandwidth analysis and honest uncertainty (via update-page on MediaWiki MCP Server) |
||
| (5 intermediate revisions by the same user not shown) | |||
| Line 2: | Line 2: | ||
|brand=Mitsubishi | |brand=Mitsubishi | ||
|model_code=C-3919 | |model_code=C-3919 | ||
|variants=N | |||
|release_year=1983 | |release_year=1983 | ||
|crt_type=Computer monitor | |crt_type=Computer monitor | ||
| Line 7: | Line 8: | ||
|screen_size_in=19 | |screen_size_in=19 | ||
|aspect_ratio=4:3 | |aspect_ratio=4:3 | ||
|tvl= | |tvl=576 | ||
|mask_type=Shadow mask | |mask_type=Shadow mask | ||
|gun_type=In-line | |gun_type=In-line | ||
| Line 19: | Line 20: | ||
|frequency=50Hz,60Hz | |frequency=50Hz,60Hz | ||
|power_max=200 | |power_max=200 | ||
|image_main=Mitsubishi C-3919N front.jpg | |||
|images=Mitsubishi C-3919N front-left.jpg,Mitsubishi C-3919N right.jpg,Mitsubishi C-3919N rear.jpg,Mitsubishi C-3919N rear-right.jpg,Mitsubishi C-3919N controls.jpg,Mitsubishi C-3919N connectors.jpg,Mitsubishi C-3919N label.jpg,Mitsubishi C-3919N top.jpg | |||
|suppress_gallery=yes | |||
}} | }} | ||
The '''Mitsubishi C-3919''' is a 19-inch professional color display monitor manufactured by Mitsubishi Electric for use with the Advanced Electronics Design (AED) 512 and 767 Color Graphics Terminals. It features an in-line gun shadow mask CRT with self-convergence technology. | The '''Mitsubishi C-3919''' is a 19-inch professional color display monitor manufactured by Mitsubishi Electric for use with the Advanced Electronics Design (AED) 512 and 767 Color Graphics Terminals. It features an in-line gun shadow mask CRT with self-convergence technology. | ||
== Photos == | |||
{{EveryCRT gallery|heights=120}} | |||
== Variants == | |||
* '''C-3919N''' — NTSC/North American version (AC120V, 60Hz only) | |||
== Features == | == Features == | ||
| Line 28: | Line 38: | ||
* Self-convergence design requiring no electrical convergence adjustments | * Self-convergence design requiring no electrical convergence adjustments | ||
* Switchable 75Ω / high-impedance input termination for daisy-chaining multiple monitors | * Switchable 75Ω / high-impedance input termination for daisy-chaining multiple monitors | ||
* Loop-through outputs for daisy-chaining to additional monitors | |||
* Separate RGB and sync termination switches | |||
* Anti-spark circuit protection | * Anti-spark circuit protection | ||
* Stable convergence with less than 0.5mm deviation in the center and 0.8mm elsewhere | * Stable convergence with less than 0.5mm deviation in the center and 0.8mm elsewhere | ||
| Line 34: | Line 46: | ||
* Warm-up time of 20 minutes maximum | * Warm-up time of 20 minutes maximum | ||
The monitor | The monitor accepts RGBHV via 5 BNC connectors, supporting either composite sync (CSYNC) on the HD input alone, or separate horizontal and vertical sync using both HD and VD inputs. | ||
== Specifications == | == Specifications == | ||
| Line 42: | Line 54: | ||
* '''Linearity:''' Better than ±7% | * '''Linearity:''' Better than ±7% | ||
* '''Raster distortion:''' Less than 2% of raster height | * '''Raster distortion:''' Less than 2% of raster height | ||
== TVL derivation == | |||
The 576 TVL figure is derived from the AED 512/767 graphics terminals that typically drove these monitors. Per the AED users manual, the highest resolution raster mode is 768×575 pixels. Since TVL measures horizontal resolution across picture height, the pixel count is adjusted for 4:3 aspect ratio: | |||
: 768 pixels × (3 ÷ 4) = '''576 TVL''' (addressable) | |||
'''Could the monitor resolve more with a different source?''' | |||
The monitor's video bandwidth is specified at 20 MHz (±3dB). This represents how fast the video amplifier can switch the electron beam intensity. At the maximum 24 kHz horizontal scan rate, each line is ~41.7 µs, with ~32 µs of active video (after blanking). A rough estimate: | |||
: 32 µs × 20 MHz = ~640 cycles (line pairs) per line | |||
Applying real-world factors (the -3dB spec means signal is already attenuated ~30% at that frequency), practical resolution from the electronics might be 500–600 pixels horizontally — which aligns reasonably well with the 768-pixel AED mode. | |||
'''Unknowns:''' | |||
The shadow mask pitch is not specified in the AED manual. Without knowing the phosphor dot spacing, we cannot determine whether the video amplifier or the shadow mask is the true resolution bottleneck. The 576 TVL figure should be considered an estimate based on the AED system configuration, not a definitive monitor specification. | |||
{{CRT voltage range | {{CRT voltage range | ||
| Line 53: | Line 82: | ||
{{CRT input | {{CRT input | ||
|label=RGB In | |label=RGB In | ||
|signal= | |signal=RGBHV | ||
|connector=BNC | |connector=BNC | ||
|count=1 | |count=1 | ||
|audio=None | |audio=None | ||
|sync=CSYNC | |sync=HSYNC+VSYNC | ||
|location=rear | |||
|notes=5 BNC connectors (R, G, B, HD, VD). HD input accepts composite sync (CSYNC) or horizontal sync; VD accepts vertical sync. Use HD alone for CSYNC operation. | |||
}} | |||
{{CRT output | |||
|label=RGB Loop | |||
|output_type=Video | |||
|signal=RGBHV | |||
|connector=BNC | |||
|count=1 | |||
|location=rear | |location=rear | ||
|notes= | |notes=5 BNC loop-through outputs for daisy-chaining additional monitors. Set termination switches to HI when looping through. | ||
}} | }} | ||
Latest revision as of 02:19, 26 February 2026
The Mitsubishi C-3919 is a 19-inch professional color display monitor manufactured by Mitsubishi Electric for use with the Advanced Electronics Design (AED) 512 and 767 Color Graphics Terminals. It features an in-line gun shadow mask CRT with self-convergence technology.
Photos
Variants
- C-3919N — NTSC/North American version (AC120V, 60Hz only)
Features
The C-3919 is designed for high-resolution graphics display, capable of showing up to 2000 characters or 441,600 pixels (768×575 maximum resolution). Key features include:
- Self-convergence design requiring no electrical convergence adjustments
- Switchable 75Ω / high-impedance input termination for daisy-chaining multiple monitors
- Loop-through outputs for daisy-chaining to additional monitors
- Separate RGB and sync termination switches
- Anti-spark circuit protection
- Stable convergence with less than 0.5mm deviation in the center and 0.8mm elsewhere
- Video amplifier frequency response of ±3dB from 50Hz to 20MHz
- Rise and fall times shorter than 20ns
- Warm-up time of 20 minutes maximum
The monitor accepts RGBHV via 5 BNC connectors, supporting either composite sync (CSYNC) on the HD input alone, or separate horizontal and vertical sync using both HD and VD inputs.
Specifications
- Video input levels: 0.7–1.5 Vp-p for RGB, 1.0–5.0 Vp-p for sync
- Blanking time: Horizontal <9.5μs, Vertical <0.8μs
- Raster size regulation: <4mm change with 0–200μA beam current
- Linearity: Better than ±7%
- Raster distortion: Less than 2% of raster height
TVL derivation
The 576 TVL figure is derived from the AED 512/767 graphics terminals that typically drove these monitors. Per the AED users manual, the highest resolution raster mode is 768×575 pixels. Since TVL measures horizontal resolution across picture height, the pixel count is adjusted for 4:3 aspect ratio:
- 768 pixels × (3 ÷ 4) = 576 TVL (addressable)
Could the monitor resolve more with a different source?
The monitor's video bandwidth is specified at 20 MHz (±3dB). This represents how fast the video amplifier can switch the electron beam intensity. At the maximum 24 kHz horizontal scan rate, each line is ~41.7 µs, with ~32 µs of active video (after blanking). A rough estimate:
- 32 µs × 20 MHz = ~640 cycles (line pairs) per line
Applying real-world factors (the -3dB spec means signal is already attenuated ~30% at that frequency), practical resolution from the electronics might be 500–600 pixels horizontally — which aligns reasonably well with the 768-pixel AED mode.
Unknowns:
The shadow mask pitch is not specified in the AED manual. Without knowing the phosphor dot spacing, we cannot determine whether the video amplifier or the shadow mask is the true resolution bottleneck. The 576 TVL figure should be considered an estimate based on the AED system configuration, not a definitive monitor specification.
