hese sapphire gigatrimmers have been selected from different types for their excellent features. Our aim is to propose 3 types with very good performances, which are better than other gigatrimmers and really offer top quality for RF and microwave applications.
Sapphire is the best material for: Insulation, heat dissipation and Q in microwave applications. It is completely chemically inert and has a very low moisture absorption value, which is even better than that of aluminium oxide.
Even though it is very small, it is often used for high power applications.
Comparison chart among the best microwave materials
Sapphire
Alumina AL2O2
Quartz SiO2
Pure Teflon
Dielectric constant εr
about 11
about 10
about 3.8
about 2,05
dissipation factor tanδ @ 10GHz
< 0,0001
0,0002
0.0015
0.0003
Thermal stability
good
good
good
poor
Mechanical performance
good
good
good
poor
Thermal dissipation
very good
good
average
poor
Main applications:
Very high Q, about 2-3 times higher than other gigatrimmers, they are suitable for low noise VCO and oscillators up to X-band (12 GHz for model CVG-Z5 27263). Considerable applicable power ex. 50 W / 2 GHz tanks for sapphire isolation and 500 V work (1000 V test and 1500 V break), very good for medium power matching, they are often used on the last TX stage in 1.9 GHz mobile base station with 50 W NP0 very high thermal stability, they are suitable for trimming in oscillators, OCXO thermostats working at high temperatures (+70°C/+90°C). They are easy to mount, this type of enclosure is perfect for PCB mounting, for easy tuning the rotor touching the screwdriver is soldered directly to the ground Very small size and very fine tuning resolution with multiturn control. It is suitable for military specifications MIL STD 202E and C-14409.
