Production timecode, from app to GPS hardware
Every camera on set. One shared second.
Generate frame-accurate SMPTE LTC on the iPhone, iPad, Mac, and Apple TV you already own. For dedicated operation, Holly LTC Core brings the same workflow to a standalone, GPS-disciplined generator.
Holly Timecode is free today · Holly LTC Core is in pre-production
One workflow, from pocket to rack
The free app covers fast, flexible LTC. Dedicated Holly hardware adds an independent, always-on timebase disciplined by GPS.
Holly Timecode
App for iPhone, iPad, Mac, and Apple TV
A focused LTC generator with named presets, explicit DF and NDF selection, and optional GeoLTC metadata in the user bits.
Learn moreHolly LTC Core
Handheld GPS-disciplined generator
Dedicated format controls, GPS discipline, temperature-compensated holdover, and switchable line- or mic-level LTC in a pocket-sized enclosure.
Explore the CoreHolly LTC Rack
1U rackmount generator
The Core's GPS-disciplined timebase in a 1U format, with a large LED timecode readout and rear-panel balanced XLR output.
Explore the rackSecond Stick
App for iPhone and iPad
A complete digital toolkit for the second AC: slate, LTC, GPS logging, sun and moon tracking, and AR shadow preview.
Explore Second StickHolly Timecode: professional LTC from the devices you already own
Choose a timecode format, recall a preset, confirm the wired output, and start generating. Holly Timecode makes a correct LTC setup quick to establish and easy to verify before the first jam.
- SMPTE 12M, precisely implementedThe SMPTE 12M encoder is verified against reference vectors for consistent frame counts and user bits on every platform.
- Six production formats23.976, 24, 25, 29.97 drop-frame, 29.97 non-drop, and 30 fps. Both counting modes are available at 29.97.
- GeoLTC user bitsCarry the date, a fixed position, or live GPS with heading, pitch, and roll inside the timecode stream.
- Named presetsSave a setup per client, truck, or camera package and recall it in one tap. Presets sync through your own iCloud.
- Verified wired outputRoute detection confirms that LTC is leaving through headphone, USB audio, or HDMI. Bluetooth is excluded from the timecode signal path.
- Apple TV display modeA full-screen wall clock with LTC over HDMI audio, burn-in drift, and a status border you can read across the room.
- Native on the MacKeyboard shortcuts for start, stop, lock, test tone, and display mode, right at the cart.
- Private by designNo account, no analytics, no ads. Everything runs on the device.
Every feature is free. Optional support subscriptions are simply a way to support continued development.
Holly LTC Core: GPS-disciplined LTC, independent of a phone
Holly LTC Core is a standalone generator designed for long production days. Connect USB-C power and an active antenna, select a timecode format, and it holds the count to GPS without depending on a phone or network.
Holly LTC Core is in pre-production. Orders are not yet open, and specifications, pricing, and availability are not yet announced. Request hardware updates for release news.
- GPS disciplineThe Core derives UTC and a qualified timing pulse from GNSS. LOCK appears only when both the time solution and reference pulse are valid.
- Temperature-compensated holdoverWhen GPS is temporarily unavailable, a ±3.5 ppm temperature-compensated oscillator carries the count. During lock, it is calibrated against GPS every hour.
- One-touch format selectionEach timecode format has a dedicated illuminated button. Changes take effect on a clean frame boundary, without menus or button combinations.
- Line- or mic-level LTCThe 3.5 mm output switches between line level for recorders and mic level for camera inputs. A scratch mic on the ring can carry guide audio on the same cable.
- Status at a glanceDedicated LOCK and HOLDOVER indicators show whether the count is GPS-disciplined or running on the internal clock. The active rate indicator also reports holdover confidence.
- Production-friendly powerRun the Core from a USB-C power bank or a recorder's 5 V accessory port. A CR123A backup cell preserves clock and GNSS state between power cycles.
- Local display, UTC metadataSelect a UTC offset for the local-time display without changing the UTC date or user bits carried in the LTC stream.
- Deterministic LTC timingThe design targets no more than 2 microseconds of edge jitter, with controlled transitions for reliable decoding by cameras and recorders.
Holly LTC Rack: the Core timebase, ready for the rack
Holly LTC Rack brings the Core into a studio-ready 1U format, pairing a large front-panel timecode display with balanced LTC on a rear XLR.
- A full timecode readoutA bright eight-digit LED display presents the running HH:MM:SS:FF count at a glance, even from across the room.
- The Core timebase insideThe rack model uses the same GPS discipline, format controls, and temperature-compensated holdover as the handheld Core.
- Balanced rear-panel outputA rear-panel balanced XLR output is designed for a clean connection to distribution and production equipment.
Holly LTC Rack is in development alongside the Core. Orders are not yet open, and final configuration, pricing, and availability are not yet announced.
Second Stick: timecode, slate, and location in one app
Second Stick combines the Holly timecode engine with the tools a second AC needs throughout the day: a digital slate, location records, sun and moon data, and AR shadow preview.
Digital slate
Track scene, take, camera roll, and sound roll with unlimited history, then export CSV, JSON, or DaVinci Resolve markers.
Production timecode built in
Generate SMPTE 12M in all six production formats, with optional GeoLTC metadata in the user bits.
Location in every format
Decimal degrees, DMS, MGRS, and UTM, with GPS logs you can export.
Sun and moon
Golden hour, blue hour, and moon phase from the NOAA solar model.
AR shadow preview
Place a block on the location and scrub from sunrise to sunset to see where the shadow lands.
From GPS reference to production timecode
GPS gives every receiver the same reference second. The Holly family turns that reference into SMPTE timecode and, when requested, carries location in the same stream.
The app follows the device clock; the Core follows GPS. Both produce the same SMPTE LTC format on the wire.
What GeoLTC puts in the user bits
GeoLTC carries location metadata alongside timecode without another cable:
- Date: the UTC calendar date, the mode the Core hardware uses.
- Static: one frame carrying the position to about a kilometer.
- Live: an eight-frame cycle with latitude, longitude, altitude, heading, attitude, velocity, and a checksum, refreshing about three times a second at 24 fps.
App, handheld, or rack
Choose the form factor that fits the run time, signal path, and installation.
| Holly Timecode app | Holly LTC Core | Holly LTC Rack | |
|---|---|---|---|
| Timecode source | Device time of day or any custom start | GPS-disciplined with TCXO holdover | The Core timebase |
| Rate / counting | 23.976, 24, 25, 29.97 DF, 29.97 NDF, 30 | 23.976, 24, 25, 29.97 DF, 29.97 NDF, 30 | 23.976, 24, 25, 29.97 DF, 29.97 NDF, 30 |
| Output | Headphone or USB audio; HDMI on Apple TV | 3.5 mm TRS at line or mic level | Balanced XLR on the rear panel |
| GPS | GeoLTC user bits from the device location | GPS time discipline; UTC date in the user bits | Core GPS discipline and UTC user bits |
| Holdover | Follows the device clock | ±3.5 ppm TCXO, calibrated hourly while GPS-locked | Core TCXO holdover |
| Display | Full-screen display mode on Mac and Apple TV | Rate, LOCK, and HOLDOVER lamps | HH:MM SS.FF LED front panel |
| Power | The device battery | USB-C 5 V, with a CR123A clock backup | USB-C 5 V |
| Availability | Available free on the App Store | Pre-production; updates available | In development |
Specifications and design targets
Holly Timecode
- Format
- SMPTE 12M linear timecode, 80 bits per frame
- Rate / counting
- 23.976, 24, 25, 29.97 DF, 29.97 NDF, and 30 fps; fractional rates as exact 24000/1001 and 30000/1001
- User bits
- UTC date, GeoLTC static, GeoLTC live, custom, or none
- Output
- Wired headphone or USB audio at the negotiated sample rate; HDMI audio on Apple TV; levels from 0 to −18 dBFS
- Platforms
- iPhone, iPad, Mac, and Apple TV
- Price
- Free, with optional support subscriptions
Holly LTC Core — design targets
- GNSS
- Multi-constellation GNSS with a precise reference pulse; biased SMA input for an active antenna
- Timing core
- GPS-disciplined timing core with a ±3.5 ppm temperature-compensated holdover clock
- Holdover
- Design target: no more than 0.3 s per day before calibration; calibrated against GPS every hour while locked
- Output
- 3.5 mm TRS: LTC on the tip at line (0.87 Vpp) or mic (11 mVrms) level, with scratch mic on the ring
- Controls
- Six illuminated format buttons, UTC offset up and down, and GNSS LOCK and HOLDOVER indicators
- Power
- USB-C 5 V under 300 mA; CR123A backup for the clock and GNSS state
- Size
- 85 × 85 × 33 mm translucent enclosure
Holly LTC Rack — design targets
- Readout
- Two 0.56-inch four-digit LED modules showing HH:MM SS.FF
- Timebase
- The same GPS-disciplined timebase and holdover system as Holly LTC Core
- Panel
- 1U rackmount format; final mechanical specification pending
- Output
- Balanced LTC on a rear-panel XLR
- Status
- In development; final configuration and availability not yet announced
Second Stick
- Slate
- Scene, take, camera roll, sound roll; unlimited history; CSV, JSON, and DaVinci Resolve marker export
- Timecode
- The same SMPTE 12M engine with GeoLTC user bits
- Location
- Decimal degrees, DMS, MGRS, and UTM with exportable GPS logs
- Sun and moon
- NOAA solar model, golden and blue hour, moon phase, AR shadow preview
- Platforms
- iPhone and iPad
- Price
- Free, with optional support subscriptions
Frequently asked questions
Is Holly Timecode really free?
Yes. Every feature is included on every platform. Optional support subscriptions help fund continued development but do not change the app or unlock additional features.
Can the app replace a hardware timecode generator?
For jam sync and many field workflows, yes. The app generates SMPTE LTC over a wired signal path and makes the correct setup quick to recall. Dedicated hardware is the better fit for an independent, always-on source that must remain GPS-disciplined throughout the day.
What does GPS add to timecode?
In the hardware, GPS provides a common time reference, allowing separate Core units to agree on the same second without first being jammed together. In the app, GeoLTC uses the LTC user bits to carry the date and, optionally, position and heading alongside the count.
When can I buy the Holly LTC Core?
Not yet. Holly LTC Core is in pre-production, and orders are not open. Specifications remain subject to production validation; pricing and availability are not yet announced. Request hardware updates for release news.
Which output should I use?
Use a wired signal path. On iPhone and iPad, connect a headphone or USB audio adapter; on Mac, use any wired audio output; on Apple TV, use HDMI audio. The Core uses a 3.5 mm jack switchable between line and mic level, and a TS-to-BNC cable connects equipment with a BNC timecode input. Bluetooth is not offered for timecode output.
Does the hardware need the app?
No. The Core is a standalone generator: power it over USB-C, connect an active GNSS antenna, and select a timecode format. The app and hardware share the same timecode engine and operating principles, but neither depends on the other.
Start with the free app today
Holly Timecode is available now. Request updates on Holly LTC Core and the 1U rack model.