Are there any plans to provide alternative connector type test leads and calibration kits such as N-type, BNC, UHF, TNC, APC, F-type, PL259, SMB, MCX, MMCX?
Not at present, but we would be interested to know your requirements.
The SMA and PC3.5 connectors on the PicoVNA make ideal relatively low-uncertainty ports from which to port-adapt both to the larger format and legacy interfaces and to the emerging smaller format and point-contact interfaces. In many cases, port adaptors can achieve sufficiently low measurement uncertainty for systems with connector types of poorer repeatability, and in other applications where performance is not limited by the connector.
Where measurement demands are high, you may be able to obtain port adaptors with either de-embed data or reference plane offset values; both these correction mechanisms being supported by the PicoVNA. In the absence of data, you can purchase a mating pair of port adapters such as PC3.5(f/m) to N(m) and PC3.5(f/m) to N(f). Mate the pair at the N-ports and measure them, then attribute half of the transmission parameters and an average of the reflection parameters to each. This is often how the manufacturer measures adaptors that are provided with data.
Ideally, the adapted ports would be calibrated with port-matching cal kits. These are available from a range of suppliers.
Likewise, within-series and adapting test leads are even more widely available than cal kits. However, it seems likely that emerging small-format connectors will demand a lighter-gauge, more flexible test lead or a flexible port adaptor. Please let us know if you have special requirements in this area.