Here is the breakout board for the RFM22B which gives you access to the pins. The RFM22B is a low-cost ISM (industrial, scientific, and medical) FSK (frequency-shift keying) transceiver module which offers communication at 434MHz and adjustable output power of up to +17 dBm. The wide operating voltage range of 1.8–3.6 V and low current consumption makes the RFM22 an ideal solution for battery powered applications.

Communication with the RFM22B is achieved via a standard 4-wire SPI interface. Three configurable general purpose I/Os are also available, the use of which can be tailored towards the needs of your project. A host of other features are also available including an 8-bit ADC, temperature sensor, RX and TX FIFOs, and low-battery detection. See the datasheet below for a complete description of every register and command.

In our testing, a 17cm wire attached to the ‘ANT’ pin worked just fine. A hole is drilled next to the ‘ANT’ pin for strain relief.

Features:

• Frequency Range = 434 MHz
• Sensitivity = -118 dBm
• +17 dBm Max Output Power (Configurable)
• Low Power Consumption
• Data Rate = 1 to 128 kbps
• Power Supply = 1.8 to 3.6 V
• Ultra low power shutdown mode
• Digital RSSI
• Wake-on-radio
• Auto-frequency calibration (AFC)
• Configurable packet structure
• Preamble detector
• TX and RX 64 byte FIFOs
• Low battery detector
• Temperature sensor and 8-bit ADC
• -40 to +85 °C temperature range
• Integrated voltage regulators
• Frequency hopping capability
• FSK, GFSK, and OOK modulation
• Low BOM
• Power-on-reset (POR)

Dimensions: 0.63x0.63in (16x16mm)

Documents:

• Schematic
• Eagle Files
• Datasheet (RFM22B)
• Product Page
• GitHub

Accessories