PicoVNA Dual E-Cal 8.5 GHz Automated calibration kit (SMA)

The PicoVNA Dual E-Cal 8.5 GHz Automated Calibration Kit is designed to simplify and improve two-port vector network analyser calibration.

The TA520 kit contains:

• TA518 SOLT-AUTO-M with two SMA male ports
• TA519 SOLT-AUTO-F with two SMA female ports
• Short, open, load and through standards within each module
• A separately characterised and polarised port adaptor
• Embedded full S-parameter characterisation data
• USB power, control and data communication
• Oven-controlled temperature stabilisation
• Protective carrying case

Together, the male and female E-Cal modules support calibration for a wider range of test cables, adaptors, fixtures and devices than a single connector configuration.

Automated SOLT Calibration

A conventional manual SOLT calibration normally requires the operator to connect several individual standards to each VNA port.

These operations may include:

• Connecting the open standard
• Connecting the short standard
• Connecting the load standard
• Connecting the through connection
• Applying the correct connector torque
• Loading characterisation data
• Repeating the process for both ports

Each additional connection introduces a possibility of:

• Incorrect standard selection
• Connector wear
• Inconsistent torque
• Contamination
• Loose connections
• Port or cable movement
• Operator error

The TA520 E-Cal kit reduces the process to a single RF connection for the selected male or female module. PicoVNA software then switches between the internal standards automatically and reads the module’s stored characterisation data over USB.

Dual Male and Female SMA Configuration

The TA520 is a dual kit containing two independent calibration modules.

The dual configuration is useful when the laboratory regularly measures devices or fixtures with different connector genders.

Typical measurement setups include:

• SMA male-to-male test cables
• SMA female-to-female devices
• Male-to-female RF components
• Insertable devices
• Non-insertable devices
• RF test fixtures
• PCB test fixtures
• Cable assemblies
• Filters and amplifiers
• Antennas and matching networks

The TA520 should not be described simply as one device with interchangeable male and female connectors. It is a kit containing two separately characterised E-Cal modules.

300 kHz to 8.5 GHz Frequency Coverage

Both E-Cal modules are characterised from:

• 300 kHz to 8.5 GHz

This frequency range covers the full measurement bandwidth of current PicoVNA instruments operating below 8.5 GHz and supports common RF applications involving:

• Cellular systems
• Wi-Fi
• Bluetooth
• GNSS
• RFID
• IoT devices
• Sub-GHz communications
• RF filters
• Amplifiers
• Antennas
• Cables and connectors
• PCB transmission lines
• Wireless modules

The calibration frequency range should be presented as 300 kHz to 8.5 GHz, not simply 8.5 GHz.

Internal Short, Open, Load and Through Standards

Each E-Cal module contains electronically switched calibration states representing:

• Short
• Open
• Load
• Through

These standards allow PicoVNA software to calculate systematic measurement-error corrections for a two-port VNA setup.

SOLT calibration can correct errors associated with:

• Directivity
• Source match
• Load match
• Reflection tracking
• Transmission tracking
• Crosstalk or isolation
• Forward measurement paths
• Reverse measurement paths

The correction is applied at the selected calibration reference planes so the displayed results more accurately represent the connected device under test.

Full S-Parameter Characterisation

Electronic standards cannot produce perfectly ideal open, short, load and through responses because internal switches, transmission paths and connectors introduce small imperfections.

Pico reduces their effect by characterising the complete RF behaviour of each module across the full operating frequency span.

The stored characterisation includes multipath S-parameter data for the internal states. PicoVNA software reads this data directly from the module through USB and uses it during calibration.

This approach compensates for the actual measured behaviour of the E-Cal module rather than treating every internal standard as mathematically ideal.

Oven-Controlled Temperature Stabilisation

Each TA518 and TA519 module includes an internal oven system that stabilises the temperature of the RF calibration standards.

Published operating details include:

• Controlled temperature range from 18°C to 28°C for quoted accuracy
• Typical warm-up time of approximately 45 seconds at 23°C
• Operating temperature range from 5°C to 40°C

Temperature stabilisation helps reduce changes in the electrical response of the internal switches, transmission paths and standards.

This supports:

• Better calibration repeatability
• More consistent S-parameter measurements
• Reduced temperature-related drift
• Reliable repeated calibration
• Improved production-test consistency

The module should be allowed to complete its warm-up process before calibration is started.

USB Power, Control and Data

The E-Cal modules use a USB 2.0 Micro connection for:

• Electrical power
• Module control
• Internal standard switching
• Characterisation-data transfer
• Device identification

A separate external power adaptor is not required for each E-Cal module.

The USB connection does not carry the RF measurement signal. RF measurements pass through the two SMA calibration ports, while USB manages the module’s control and stored reference data.

Traceable Calibration Data

Pico Technology states that its VNA calibration and check standards are calibrated against fully traceable PC3.5 standards.

The E-Cal modules are supplied with their characterisation data embedded in internal memory, allowing PicoVNA software to identify the device and apply its individual calibration information automatically.

Traceable characterisation supports applications such as:

• RF research
• Product development
• Production testing
• Quality assurance
• Calibration verification
• Measurement laboratories
• University laboratories
• Telecom component testing
• Automated RF validation

A separate NABL calibration certificate should be mentioned only if RevineTech confirms that it is included within its own commercial package. Pico’s official TA520 product page states traceability to PC3.5 standards but does not identify an NABL certificate as a standard manufacturer inclusion.

Calibration Performance

The individual TA518 and TA519 modules provide the following published calibration performance:

• Directivity: 40 dB
• Source match: 40 dB
• Load match: 36 dB
• Reflection tracking: 0.05 dB
• Transmission tracking: 0.04 dB

These specifications describe the residual calibration performance associated with the characterised E-Cal module under the stated operating conditions.

Measurement performance in a complete setup also depends on:

• VNA model
• Test cable quality
• Connector condition
• Cable movement
• Frequency range
• Measurement bandwidth
• Device mismatch
• Calibration reference plane
• Environmental stability

Port Power Limits

Each E-Cal module has published RF port limits of:

• +10 dBm maximum normal operating input
• +20 dBm or 1 V peak protection limit

The protection rating should not be treated as a normal operating level.

Before calibration, the VNA source power should be checked to ensure that it remains within the specified operating limit.

Calibration Workflow

A typical automated calibration process includes:

1. Allow the PicoVNA, test cables and E-Cal module to stabilise.
2. Inspect and clean the SMA connectors.
3. Select the required TA518 male or TA519 female module.
4. Connect the module to the two VNA reference planes.
5. Apply the correct SMA connector torque.
6. Connect the module to the computer through USB.
7. Start the E-Cal procedure in PicoVNA software.
8. Allow the software to identify the module and read its stored data.
9. Permit the module to switch automatically between its standards.
10. Complete and save the calibration.
11. Disconnect the E-Cal module and connect the device under test.
12. Use a suitable check standard where independent validation is required.

The E-Cal module automates the standards, but correct connector handling, cable positioning and reference-plane selection remain essential.

Reduced Connector Operations

One of the principal benefits of E-Cal is the reduction in repeated connect and disconnect operations.

Fewer connections can help:

• Reduce calibration time
• Minimise connector wear
• Improve operator consistency
• Lower contamination risk
• Reduce torque variation
• Avoid selecting the wrong standard
• Support more frequent calibration
• Improve production throughput

Automated calibration is particularly useful in environments where calibrations are repeated regularly or performed by several operators.

Applications

The PicoVNA Dual E-Cal Kit is suitable for:

• PicoVNA calibration
• RF component testing
• Antenna measurements
• Filter testing
• Amplifier characterisation
• Cable and connector analysis
• PCB transmission-line testing
• Wireless module development
• Production-line RF testing
• Automated test equipment
• Telecom component validation
• Research laboratories
• University RF laboratories
• Calibration verification
• Measurement assurance programmes
• Field and service applications