Ecto-1A LED Sign Boards
10 min read
The Ecto-1A LED sign boards are the two roof-mounted dot-matrix signs added to the Ecto-1 for Ghostbusters II (1989), when the car was upgraded to the Ecto-1A. One board faces each side of the car and both always show the same content: a looping sequence of red, green and amber messages such as GHOSTBUSTERS, WE'RE BACK and WHO YA GONNA CALL? US!, along with the phone number CALL JL5-2020.
This page collects what the community has worked out about the boards: the hardware, the full message list and running order, the fonts, colors and animations, and build plans and files for making a screen-accurate replica. Most of it comes from the GBFans reference thread Screen Accurate ECTO-1A Dot Matrix LED Sign (Reference).1 Details that are still uncertain are marked unconfirmed, and effects that have been reconstructed rather than observed are marked inferred.
Hardware
- Resolution: 80 columns × 7 rows, counted from film frames.1
- Pixels: each pixel is a cluster of 4 LEDs. The clusters are never driven separately.1
- Colors: every pixel has a red cluster and a green cluster. Lighting both reads as amber or yellow on screen; there is no separate yellow LED.12
- Green offset: the green clusters sit slightly lower than the red ones. It shows wherever red and green text meet, for example where "BACK" doesn't line up with "WE'RE".13
- LED count: 560 pixels per color, 4,480 LEDs per board.1
- Two boards, one per side, always showing the same content.1
- Manufacturer: unknown. The thread's investigation is ongoing.
## Messages
The boards cycle through twelve screens. The IDs A–L follow prodestrian's breakdown in the reference thread.1
- A — GHOSTBUSTERS: bold narrow font, edge to edge. Red, then green, with rapid red/green swaps.
- B — FOR HIRE…: bold narrow font, red text inside a green border.
- C — WE'RE READY: font and color unconfirmed. Shown here in the thin font in amber.
- D — TO BELIEVE YOU: thin font. Red, with one word highlighted at a time: TO in green, BELIEVE in amber, then YOU (YOU's color is inferred as green).
- E — CALL JL5-2020: thin font, amber.
- F — GHOSTBUSTERS: second appearance, green and then red.
- G — WE'RE BACK: bold wide font, filling all 80 columns. WE'RE red and BACK green, then the colors swap.
- G2 — five lines → green boxes: a graphic between WE'RE BACK and WHO YA (see Inferred effects).
- H — WHO YA: bold wide font, red.
- I — GONNA: bold wide font, color unconfirmed (shown red).
- J — CALL?: bold wide font, red.
- K — US!: bold wide font, red, between two green arrows that point inward at the word.
- L — CALL JL5-2020: second appearance, amber, which then loops back to A.



## Sequence and animation
## Inferred effects
The thread also mentions a possible bounce and an upside-down flip of GHOSTBUSTERS. These are hedged ("seems", "possibly") and are left out of the recreation.











### Timing