brickbots · brickbots · Jun 8, 2026
diff --git a/.claude/skills/docs/references/product-knowledge-base.md b/.claude/skills/docs/references/product-knowledge-base.md
@@ -237,7 +237,7 @@ The PiFinder has a digital alignment system that maps where within its 10° fiel
 - **Physical alignment vs digital alignment**: When a customer reports alignment problems, first verify they understand the alignment procedure (especially the SQUARE button press). If the camera is physically pointed too far from the telescope's optical axis (>5 degrees), no amount of digital alignment will help — the star won't be in the camera's FOV at all.
 
 ### Finding Objects & Push-To Guidance
-- Access objects via main menu → **Objects** → choose **By Catalog**, **All Filtered**, **Recent** (session history), or **Name Search** (T9-style text entry).
+- Access objects via main menu → **Objects** → choose **By Catalog**, **All Filtered**, **Recent** (session history), or **Name Search** (keypad text entry).
 - In object lists, pressing **SQUARE** cycles through info displays: catalog designation → common names → magnitude/size with observation checkmarks.
 - **Push-to guidance** (from Object Details screen):
   - **Top number**: Rotational direction (CW/CCW) and degrees to move
@@ -403,7 +403,7 @@ The PiFinder connects to SkySafari (and other planetarium apps) via WiFi using t
 - PiFinder initially sends 0° RA/DEC until the first plate solve completes
 - Works with **SkySafari 5 Plus, 6, and 7** (7 is most reliable)
 - SkySafari can lock the view to the scope's position
-- SkySafari can send objects to PiFinder's observing list (useful alternative to T9 keypad entry)
+- SkySafari can send objects to PiFinder's observing list (useful alternative to keypad text entry)
 - **Single connection limit**: Only one device/app can connect to the PiFinder's LX200 server at a time. If SkySafari is connected on an iPhone, it must be disconnected before connecting from an iPad (or vice versa).
 - **SkySafari cannot connect to PiFinder and a GoTo mount simultaneously** — choose one
 - **Sleep mode warning**: If PiFinder enters sleep mode, it stops sending position updates. Extend or disable the sleep timer if using SkySafari continuously.

diff --git a/default_config.json b/default_config.json
@@ -6,7 +6,6 @@
     "auto_exposure_zero_star_handler": "sweep",
     "menu_anim_speed": 0.1,
     "text_scroll_speed": "Med",
-    "t9_search": false,
     "screen_direction": "right",
     "mount_type": "Alt/Az",
     "solver_debug": 0,

diff --git a/docs/ax/catalog.md b/docs/ax/catalog.md
@@ -36,7 +36,6 @@ At a high level:
         └─► Catalogs object (single instance shared across the app)
                  │
                  ├── CatalogFilter (one shared instance set on every catalog)
-                 ├── T9 / text search caches
                  └── Iterates as List[Catalog], each holding List[CompositeObject]
 ```
 
@@ -119,7 +118,7 @@ External code is expected to read through `get_objects()` (returns a
 ### 2.5 `Catalogs`
 
 A container that holds a `List[Catalog]` plus the singleton
-`CatalogFilter` and the T9 search cache. It exposes:
+`CatalogFilter`. It exposes:
 
 - `filter_catalogs()` — runs `filter_objects()` on every catalog.
 - `set_catalog_filter(filter)` — installs one filter object on every
@@ -131,10 +130,9 @@ A container that holds a `List[Catalog]` plus the singleton
 - `get_catalog_by_code(code)` / `get_object(code, sequence)` — direct
   lookup.
 - `search_by_text(s)` — substring match against all names (selected or
-  not, filtered or not).
-- `search_by_t9(digits)` — see §5.
+  not, filtered or not). See §5.
 - `add(catalog)` / `remove(code)` / `set(catalogs)` — mutate the
-  collection and invalidate the T9 cache.
+  collection.
 - `is_loading()` — reports whether the background loader thread is
   still alive (UI uses this to show a "still loading" indicator).
 - `__iter__` — yields only selected catalogs.
@@ -254,31 +252,17 @@ filter is restored on app start.
 
 ## 5. Search
 
-### 5.1 Text search
-
 `Catalogs.search_by_text(s)` does a substring lower-case match against
 each name on each object. Returns a `List[CompositeObject]`. No indexing
-— it's O(n_names) per call but fine in practice.
-
-### 5.2 T9 (keypad) search
-
-PiFinder's hardware keypad uses a non-standard digit-to-letter mapping
-(`KEYPAD_DIGIT_TO_CHARS` at the top of `catalogs.py` — note `7→abc`,
-`1→tuv`, `3→'-+/`, etc.). `Catalogs.search_by_t9(digits)`:
-
-1. Translates every object name to its digit-form via a
-   `str.maketrans` table.
-2. Filters out characters that aren't valid T9 digits.
-3. Caches `(catalog_code, sequence) → list[digit_string]` in
-   `_t9_cache`, invalidated when catalogs are added/removed/replaced.
-4. Returns any object whose digit string contains the search pattern as
-   a substring (skipping objects whose digit string is shorter than the
-   query, since the substring couldn't match).
-
-The cache is rebuilt lazily by `_ensure_t9_cache(objs)` only if the
-dirty flag is set **or** the set of object keys has changed since the
-last rebuild — so dynamic catalogs (PL, comets) updating their
-positions don't trigger a rebuild as long as their key set is stable.
+— it's O(n_names) per call but fine in practice. It is the only catalog
+search.
+
+On the hardware keypad, `UITextEntry` builds the search string with
+multitap entry: each number key cycles through its letters (the keypad
+uses a non-standard layout — `7→abc`, `1→tuv`, `3→'-+/`, etc.), and the
+resulting text is passed to `search_by_text`. (An earlier `t9_search`
+option that matched names against keypad-digit sequences has been
+removed.)
 
 ---
 

diff --git a/docs/ax/catalog/CONTEXT.md b/docs/ax/catalog/CONTEXT.md
@@ -59,7 +59,7 @@ A `CatalogBase` (object list + sequence/id indices) plus filtering: holds the sh
 _Avoid_: catalog object, catalog instance — use `Catalog` when the class is meant.
 
 **Catalogs** (the catalog collection):
-The container of `Catalog`s. Owns the singleton `CatalogFilter` and the T9/text search caches; this is the runtime API used by the UI and web. In prose, say "the catalog collection"; reserve `Catalogs` (code-style) for the type itself.
+The container of `Catalog`s. Owns the singleton `CatalogFilter`; this is the runtime API used by the UI and web. In prose, say "the catalog collection"; reserve `Catalogs` (code-style) for the type itself.
 _Avoid_: catalog list, catalog set, the catalogs object.
 
 ### Filtering
@@ -149,13 +149,9 @@ _Avoid_: catalog state (the enum is `CatalogState`; the wrapper is `CatalogStatu
 ### Search
 
 **Text search** (`search_by_text`):
-Lower-case substring match against every name in every catalog. Selection and filter state are ignored.
+Lower-case substring match against every name in every catalog. Selection and filter state are ignored. This is the only catalog search; the on-screen keypad in `UITextEntry` uses multitap (cycle through a key's letters) to build the search string.
 _Avoid_: name search, full-text search.
 
-**T9 search** (`search_by_t9`):
-Substring search after translating names to PiFinder's non-standard keypad-digit form (`KEYPAD_DIGIT_TO_CHARS` — `7→abc`, `1→tuv`, …). Backed by `_t9_cache` keyed on `(catalog_code, sequence)`.
-_Avoid_: keypad search, digit search (use T9 search for the public concept).
-
 ### UI helpers
 
 **CatalogDesignator**:

diff --git a/docs/ax/ui.md b/docs/ax/ui.md
@@ -364,7 +364,7 @@ hardware, or network dependency at construct or update time — are:
 | `UIObjectList` | `object_list.py:108` | Reads `catalogs` heavily (filtered/by-code lists). Loads marker PNGs from `PiFinder/markers/`. Constructor mutates the passed `item_definition` (`select`/`items`). |
 | `UIObjectDetails` | `object_details.py:56`, `:77` | Requires `item_definition["object"]` and `["object_list"]`. Opens an `ObservationsDatabase` (SQLite, `~/PiFinder_data/observations.db`). Reads `catalogs`, `shared_state`. |
 | `UILog` | `log.py:30`, `:44` | Requires `item_definition["object"]`. Opens `ObservationsDatabase`. |
-| `UITextEntry` | `textentry.py:104` | In catalog-search mode opens `ObjectsDatabase` (the bundled `pifinder_objects.db`) and calls `catalogs.search_by_t9` / `search_by_text`. |
+| `UITextEntry` | `textentry.py:104` | In catalog-search mode opens `ObjectsDatabase` (the bundled `pifinder_objects.db`) and calls `catalogs.search_by_text`. |
 | `UISQM` | `sqm.py:54` | `update()` calls `self.camera_image.copy()` — needs a real `camera_image` (a `PIL.Image`, **not** `None`). Reads `shared_state.sqm()`, sends camera commands. |
 | `UIPreview` | `preview.py:213` | Also `self.camera_image.copy()` — needs a real camera image; reads `shared_state.last_image_metadata()`. |
 | `UISoftware` | `software.py:55`–`:74` | Constructor `open()`s `version.txt` and `wifi_status.txt` from `utils.pifinder_dir` (must exist). Update path does `requests.get(...)` to GitHub — network. |

diff --git a/docs/source/user_guide.rst b/docs/source/user_guide.rst
@@ -347,7 +347,7 @@ four options:
   for observing projects and finding the nearest objects in a particular catalog.
 - **Recent**: Starts empty and builds a history of the objects you've checked out during
   the current session.
-- **Name Search**: Using the number keypad and T9-style text entry, search for objects by
+- **Name Search**: Using the number keypad and keypad text entry, search for objects by
   name.  The Snowball planetary?  Cat's Eye?  This is the way to find them.
 
 However you build the list, it always displays the same information and offers the same
@@ -490,7 +490,7 @@ screen, select it from the Objects menu:
 
 .. image:: images/user_guide/name_search_01.png
 
-It uses T9-style text input, like the cellphones from the dawn of text messaging.  The
+It uses keypad text input, like the cellphones from the dawn of text messaging.  The
 on-screen keypad shows the letters available by pressing each number key several times in a
 row.
 

diff --git a/python/PiFinder/catalogs.py b/python/PiFinder/catalogs.py
@@ -1,6 +1,5 @@
 # mypy: ignore-errors
 import logging
-import re
 import time
 import datetime
 import pytz
@@ -28,31 +27,6 @@
 
 logger = logging.getLogger("Catalog")
 
-# Mapping from keypad numbers to characters (non-conventional layout)
-KEYPAD_DIGIT_TO_CHARS = {
-    "7": "abc",
-    "8": "def",
-    "9": "ghi",
-    "4": "jkl",
-    "5": "mno",
-    "6": "pqrs",
-    "1": "tuv",
-    "2": "wxyz",
-    "3": "'-+/",
-}
-
-LETTER_TO_DIGIT_MAP: dict[str, str] = {}
-for _digit, _chars in KEYPAD_DIGIT_TO_CHARS.items():
-    # Map the digit to itself so numbers in names still match
-    LETTER_TO_DIGIT_MAP[_digit] = _digit
-    for _char in _chars:
-        LETTER_TO_DIGIT_MAP[_char] = _digit
-        LETTER_TO_DIGIT_MAP[_char.upper()] = _digit
-
-translator = str.maketrans(LETTER_TO_DIGIT_MAP)
-VALID_T9_DIGITS = "".join(KEYPAD_DIGIT_TO_CHARS.keys())
-INVALID_T9_DIGITS_RE = re.compile(f"[^{VALID_T9_DIGITS}]")
-
 # collection of all catalog-related classes
 
 # CatalogBase : just the CompositeObjects (imported from catalog_base)
@@ -366,8 +340,6 @@ class Catalogs:
     def __init__(self, catalogs: List[Catalog]):
         self.__catalogs: List[Catalog] = catalogs
         self.catalog_filter: Union[CatalogFilter, None] = None
-        self._t9_cache: dict[tuple[str, int], list[str]] = {}
-        self._t9_cache_dirty = True
 
     def filter_catalogs(self):
         """
@@ -421,61 +393,6 @@ def get_object(self, catalog_code: str, sequence: int) -> Optional[CompositeObje
         if catalog:
             return catalog.get_object_by_sequence(sequence)
 
-    # this is memory efficient and doesn't hit the sdcard, but could be faster
-    # also, it could be cached
-    def _name_to_t9_digits(self, name: str) -> str:
-        translated_name = name.translate(translator)
-        return INVALID_T9_DIGITS_RE.sub("", translated_name)
-
-    def _object_cache_key(self, obj: CompositeObject) -> tuple[str, int]:
-        return (obj.catalog_code, obj.sequence)
-
-    def _invalidate_t9_cache(self) -> None:
-        self._t9_cache_dirty = True
-
-    def _rebuild_t9_cache(self, objs: list[CompositeObject]) -> None:
-        self._t9_cache = {}
-        for obj in objs:
-            self._t9_cache[self._object_cache_key(obj)] = [
-                self._name_to_t9_digits(name) for name in obj.names
-            ]
-        self._t9_cache_dirty = False
-
-    def _ensure_t9_cache(self, objs: list[CompositeObject]) -> None:
-        current_keys = {self._object_cache_key(obj) for obj in objs}
-        if self._t9_cache_dirty or current_keys != set(self._t9_cache.keys()):
-            self._rebuild_t9_cache(objs)
-
-    def search_by_t9(self, search_digits: str) -> List[CompositeObject]:
-        """Search catalog objects using keypad digits.
-
-        Uses the existing keypad letter mapping (including its non-conventional
-        layout) to convert object names to their digit representation and
-        returns all objects whose digit string contains the search pattern.
-        """
-
-        objs = self.get_objects(only_selected=False, filtered=False)
-        result: list[CompositeObject] = []
-        if not search_digits:
-            return result
-
-        self._ensure_t9_cache(objs)
-
-        for obj in objs:
-            for digits in self._t9_cache.get(self._object_cache_key(obj), []):
-                if len(digits) < len(search_digits):
-                    continue
-                if search_digits in digits:
-                    result.append(obj)
-                    logger.debug(
-                        "Found %s in %s %i via T9",
-                        digits,
-                        obj.catalog_code,
-                        obj.sequence,
-                    )
-                    break
-        return result
-
     def search_by_text(self, search_text: str) -> List[CompositeObject]:
         objs = self.get_objects(only_selected=False, filtered=False)
         result = []
@@ -495,14 +412,12 @@ def search_by_text(self, search_text: str) -> List[CompositeObject]:
     def set(self, catalogs: List[Catalog]):
         self.__catalogs = catalogs
         self.select_all_catalogs()
-        self._invalidate_t9_cache()
 
     def add(self, catalog: Catalog, select: bool = False):
         if catalog.catalog_code not in [x.catalog_code for x in self.__catalogs]:
             if select:
                 self.catalog_filter.selected_catalogs.add(catalog.catalog_code)
             self.__catalogs.append(catalog)
-            self._invalidate_t9_cache()
         else:
             logger.warning(
                 "Catalog %s already exists, not replaced (in Catalogs.add)",
@@ -513,7 +428,6 @@ def remove(self, catalog_code: str):
         for catalog in self.__catalogs:
             if catalog.catalog_code == catalog_code:
                 self.__catalogs.remove(catalog)
-                self._invalidate_t9_cache()
                 return
 
         logger.warning("Catalog %s does not exist, cannot remove", catalog_code)

diff --git a/python/PiFinder/ui/menu_structure.py b/python/PiFinder/ui/menu_structure.py
@@ -702,22 +702,6 @@ def _(key: str) -> Any:
                                 },
                             ],
                         },
-                        {
-                            "name": _("T9 Search"),
-                            "class": UITextMenu,
-                            "select": "single",
-                            "config_option": "t9_search",
-                            "items": [
-                                {
-                                    "name": _("Off"),
-                                    "value": False,
-                                },
-                                {
-                                    "name": _("On"),
-                                    "value": True,
-                                },
-                            ],
-                        },
                         {
                             "name": _("Az Arrows"),
                             "class": UITextMenu,

diff --git a/python/PiFinder/ui/textentry.py b/python/PiFinder/ui/textentry.py
@@ -124,10 +124,6 @@ def __init__(self, *args, **kwargs) -> None:
         self._results_updated = False  # Flag to trigger UI refresh
         self.SEARCH_DEBOUNCE_MS = 250  # milliseconds
 
-    @property
-    def t9_search_enabled(self) -> bool:
-        return bool(self.config_object.get_option("t9_search", False))
-
     def draw_text_entry(self):
         line_text_y = self.text_y + self.bold.height + 2
         self.draw.line(
@@ -175,7 +171,7 @@ def draw_text_entry(self):
             )
 
     def draw_keypad(self):
-        # 3-column x 4-row T9 grid filling the width below the text line; key
+        # 3-column x 4-row keypad grid filling the width below the text line; key
         # size derives from the screen so it scales (38x23 on the 128 panel).
         start_x = self.text_x
         start_y = self.text_y + self.bold.height
@@ -286,10 +282,7 @@ def _perform_search(self, search_text, search_version):
             # Priority catalogs (NGC, IC, M) are loaded first, WDS loads in background
             # So search will work immediately with those, WDS results appear when loading completes
             logger.info(f"Starting search for '{search_text}'")
-            if self.t9_search_enabled:
-                results = self.catalogs.search_by_t9(search_text)
-            else:
-                results = self.catalogs.search_by_text(search_text)
+            results = self.catalogs.search_by_text(search_text)
             logger.info(f"Search for '{search_text}' found {len(results)} results")
 
             # Only update if this search is still current (not superseded by newer search)
@@ -353,15 +346,6 @@ def key_long_minus(self):
     def key_number(self, number):
         current_time = time.time()
         number_key = str(number)
-        if not self.text_entry_mode and self.t9_search_enabled:
-            # In T9 mode we simply append the pressed digit
-            self.last_key_press_time = current_time
-            self.last_key = number
-            if number_key in self.keys:
-                self.char_index = 0
-                self.add_char(number_key)
-            return
-
         # Check if the same key is pressed within a short time
         if self.last_key == number and self.within_keypress_window(current_time):
             self.char_index = (self.char_index + 1) % self.keys.get_nr_entries(