Technical FAQs

Technical questions and answers for advanced users and developers.

Hardware Technical Details

What are the exact hardware specifications?

Processor:

• Broadcom BCM2712 2.4GHz quad-core 64-bit Arm Cortex-A76 CPU
• Cryptography extensions, 512KB per-core L2 caches and a 2MB shared L3 cache
• VideoCore VII GPU, supporting OpenGL ES 3.1, Vulkan 1.3

Memory & Storage:

• 8GB LPDDR4X-4267 SDRAM (1GB, 2GB, 4GB, 8GB, and 16GB)
• 128GB microSD card (SanDisk 128GB Extreme microSDXC UHS-I)
• microSD card slot, with support for high-speed SDR104 mode
• 26GB+ content pre-loaded

Connectivity:

• Dual-band WiFi (2.4GHz and 5GHz)
• 802.11ac (WiFi 5)
• Gigabit Ethernet (Bare Bones tier and above)
• Dual 4Kp60 HDMI® display output with HDR support
• 2 × USB 3.0 ports, supporting simultaneous 5Gbps operation
• 2 × USB 2.0 ports
• 4Kp60 HEVC decoder
• Bluetooth 5.0 / Bluetooth Low Energy (BLE)
• 2 × 4-lane MIPI camera/display transceivers

Power:

• 5V/5A DC power via USB-C, with Power Delivery support
• 15W typical power consumption

Other:

• Raspberry Pi standard 40-pin header
• Real-time clock (RTC), powered from external battery (Note: purchased separately)
• Power button

Can I upgrade the storage?

Technically yes, but not recommended:

• MicroSD card is accessible
• Can upgrade to larger capacity
• Must re-image with RKPi5 software
• Contact support for imaging instructions

Can I connect external storage?

microSD or USB storage:

• Optional - USB storage mount points are built-in to the Raspberry Pi platform
• mandatory - microSD storage is where the operating system boots from
• GENERAL NOTE: The RKPi5 is complete with the microSD card that is preloaded with the operating system. At the time that the golden master microSD is created, it also loads Rapture Kit 3.1 static website content. Therefore, the single microSD card (with a best practices duplicate) is all that is needed. No external storage is required.

What operating system does it run?

RKPi5 runs a customized Linux distribution:

• Base: Raspberry Pi OS (Debian-based)
• Version: 64-bit Trixie Operating System
• Kernel: Linux 6.1+
• Web Server: Nginx
• Media Server: Custom implementation on Nginx foundation

Network & Connectivity

What are the network specifications?

As WiFi Access Point:

SSID: rapture_kit (only customizable in the installer/configuration shell scripts [advanced users only])
Security: WPA2-PSK
Channels: Auto (2.4GHz) We optimize on 2.4GHz for compatibility
Gateway: 10.42.0.1
Max Clients: 10-15

As WiFi Client:

• Does not connect to the internet
• Cannot be used as a router or Bridge
• Only serves Wi-Fi captive portal static website content
• In a client device, such as a phone, tablet, or PC, you must disconnect from the RKPi5 and join another Wi-Fi connection for default behavior
• NOTE: Any attempt to navigate to another website while connected to the 'rapture_kit' network connection will be forced back to the Rapture Kit content.

Can I change the IP address range?

• No, the IP is baked into the RKPi5 configuration scripts.
• Changing the default SSID name of 'rapture_kit' or the IP address requires editing the *.sh install scripts
• Thus, you are building a forked master image for your new specfications
• NOTE: This is not supported. You are on your own if you run into problems!

Does it support WiFi 6 (802.11ax)?

No, Raspberry Pi 5 supports WiFi 5 (802.11ac) only.

WiFi 5 is sufficient for:

• Up to 10-15 concurrent users
• HD video or MP3 audio streaming
• All current content

Software & Development

Can I SSH into the device?

SSH Access:

• Disabled by default for security!
• Can be enabled during installation of the Trixie operating system (for new builds only)
• Default port: 22
• Username/password are baked into the *.sh shell install scripts
• You can modify the user name and password in the scripts prior to forking the application

What programming languages are available?

Pre-installed:

• Python 3.11+
• Node.js 18+
• Bash
• PHP 8+

Additional languages can be installed via SSH if needed.

Can I develop custom applications?

All Tier:

• Full access to DIY scripts
• Modify as desired
• Community support available

Is there an API?

If you want a full development platform, the RKPi5 solution is not the correct starting point. What you are looking for is WAMPi.

Can I backup the entire system?

Backup Options:

• To "backup" the microSD card, use a clone tool to do an image-to-image transfer between microSD cards.
• For example, we create a golden master image on a microSD card, then use Etcher or Pi Imager to make duplicates
• This is a standard Raspberry Pi operation, not specific to the RKPi5 solution
• Duplicating the microSD is permitted. It is wise to make at least one duplicate
• microSD cards are durable, but can show signs of wear or can sometimes get corrupted
• Having a backup microSD card gives you complete fault tollerance. There is no migration beween old and new

Content & Media

What media codecs are supported?

Video:

• H.264 (AVC) - Primary
• H.265 (HEVC) - Supported
• MP4 container

Audio:

• MP3 - Primary
• AAC - Supported
• OGG/Vorbis - Supported

Subtitles:

• SRT
• VTT
• Embedded subtitles

What are the streaming bitrates?

Video Quality Options:

• 480p: ~1 Mbps (15 users simultaneously)
• 720p: ~3 Mbps (5 users simultaneously)
• 1080p: ~5 Mbps (3 users simultaneously)

Adaptive bitrate streaming adjusts based on available bandwidth.

Can I transcode media?

Transcoding is automatic:

• Server detects client capabilities
• Adjusts quality automatically
• Balances quality vs. number of users

Manual transcoding:

• Available via admin panel
• Pre-generate lower quality versions
• Saves bandwidth for large groups

Performance & Limits

What are the performance specifications?

Tested Scenarios:

| Users | Video (720p) | Audio (128k) | Text Browsing | |-------|--------------|--------------|---------------| | 1-3 | Excellent | Excellent | Instant | | 4-7 | Good | Excellent | Instant | | 8-12 | Fair | Good | Fast | | 13-15 | Limited | Good | Fast |

What are the absolute limits?

Hard Limits:

• 15 WiFi connections maximum (hardware)
• 5 simultaneous video streams (recommended)
• 15 simultaneous audio streams (recommended)
• 50 text browsers (estimated)

Soft Limits:

• Storage: 128GB (expandable)
• Battery: 6+ hours (replaceable)
• Range: ~100ft (antenna upgradeable)

Can I monitor performance?

• No. This is a feature, not a bug or limitation.
• We are trying to protect users that access the RKPi5 from hostile actors

What's included in the RKPi5 build scripts?

All tiers use the same install scripts:

• Complete setup scripts (these are .sh or shell scripts used by Linux)
• Automated installation (single script install orchestrates the other component scripts)
• Configuration templates (requires extreme expertise, don't recommend modivations)
• Content download (independent from https://rapturekit.org/download) requires a PC/Mac + monitor + keyboard + mouse
• Network setup is configured in the shell scripts and configure the Wi-Fi captive portal and static website content
• Content has a index.html page for the landing (home) page. Nginx routes to the Rapture Kit 3.1 home page automatically

What do I need to build my own?

Required Hardware:

• Raspberry Pi 5 (8GB recommended)
• MicroSD card (128GB+ recommended)
• Portable battery pack (20,000mAh+)
• USB-C power supply
• Case (optional)
• You will need a PC/Mac, monitor, keyboard, and mouse with internet connection to create a new golden master microSD card

Estimated Cost: $150-500 for all components depending on complexity and add-on options (solar panel, etc.)

Is support available for DIY builds?

DIY Support:

• Community forums (perhaps in the future)
• Documentation (free)
• Email support (paid consultation available)

Technical specifications may change during beta testing. Final specs confirmed before public launch.