Overview
SHARI (SA818 Ham Allstar Radio Interface) PiHat Allstar Node (52PI Case) is a kit construction project that implements a Pi4B hosted Allstar node using a NiceRF SA818 embedded UHF (420 – 450 MHz) or a VHF (144-148 MHz) radio module. The radio module and interface circuits are located on a custom Raspberry Pi Hat board. This Pi Hat board plugs into the Pi4B using the 40 pin GPIO connector. A JST 2 conducter cable is used to complete a USB connection to the PI4B. A complete Allstar node can be created with a SHARI PiHat 52PI Case kit, a Raspberry Pi4B (with power supply and microSD card) and an Allstar image.
This kit uses the 52Pi tall case which allows a fan to be installed inside the unit. The top cover of the case is made from Lexan with a slight “smoked” tint which permits the COMM (blinking green), COS (yellow) and PTT (red) LEDs to be viewed through the cover.
The SHARI PiHat Mod2 PC board used in this kit is implemented with surface mount parts, a NiceRF radio module with castellated holes for mounting to the PC board and 3 through-hole connectors. The board is supplied with all the small surface mount parts installed.
Features
- 52Pi tall case (3.34″L x 2.48″ W x 1.77″H) with internal fan and Pi4B heatsinks
- Uses CMedia CM108B USB Audio IC.
- Uses a NiceRF SA818 UHF (420-450 MHZ) or VHF (144-148MHz) embedded radio module (www.nicerf.com) with a lowpass output filter to meet FCC Part 97 harmonic level requirements
- 300 to 600 milliwatts RF output power
- RX/TX serial connection from the Pi4 GPIO to the SA-818 radio module to change RF module parameters including RF and CTCSS/CDCSS frequencies.
- Clamp-on ferrite provided to mitigate buzz interference from high RF fields near the Pi power supply.
- Numerous EMI control techniques including ferrites, bypass capacitors and a multilayer PC board
- Internal coax cable routes RF from U.FL (IPEX) connector to SMA antenna connector
- Raspberry Pi4B, power supply and microSD card provided by kit builder.
Construction
SHASI PiHat (52Pi case) is a kit construction project. The kit consists of the following items:
- 52Pi tall case with fan and heatsinks
- SHARI PiHat (U or V) label
- SHARI PiHat UV Mod 2 PCB with installed SMD components
- SA818S (U or V) radio module
- USB jack plug (prevents plugging a connector into the USB port used by SHARI)
- UHF (or VHF) right angle antenna
- U.FL to SMA connector cable with washer and nut
- Two 11 mm brass spacers with nuts
- 2 row, 40 pin female GPIO connector
- 2 position JST right angle female jack
- 2 conductor cable with JST male plug
- Two ferrite cores (clamp-on and dual hole for common mode)
The kit builder supplies the Raspberry Pi4B, the Pi4B power supply and a microSD card to complete the self-contained Allstar node.
Construction Manual
A comprehensive step-by-step construction/assembly manual to construct an Allstar node using the SHARI PiHat is available.
Setup Manual
A comprehensive step-by-step setup manual to set up a SHARI PiHat Allstar node using the HamVOIP image is available.
Ordering Information
SHARI PiHat (52Pi case) is designed as a kit for construction and use in the amateur radio service by licensed amateur radio operators who can assure that the unit they construct meets 47 CFR Part 97 – Amateur Radio Service required operating requirements including frequency, bandwidth and required power levels at the fundamental and harmonic frequencies.
SHARI PiHat (52Pi case) Ordering Options
- Kit – Available as a parts kit for $95 (UHF or VHF). You supply the Raspberry Pi4B, Pi4 power supply and microSD card to complete your Allstar node . Please be sure to download and study the SHARI PiHat (52Pi case) Construction Manual to be sure you own the required tools and possess the required mechanical and soldering skills to build the kit.
Additional Kit Options:
– We will solder the SA818S radio module onto the PC Board for an additional $5.
– Raspberry Pi4B and Pi4 Power supply for use with the kit for $65 - Built – We supply all the parts including the Pi4B and Pi4 power supply. You supply the microSD card and perform the setup of Allstar – A complete assembled and tested unit is $215. This option is currently available as we have Pi4-2 GB boards.
Please send an email with your name and callsign to kits4hams@gmail.com for ordering and delivery information. We will send you an order form for you to complete and return to us. This will result in you joining our wait list. When your order on our wait list is ready for processing, we will send you a customized Paypal invoice to pay.