Wideline probes
Compatibility with temperature control systems
The ATP CF probe is designed to fit into the Oxford Instruments SpectrostatNMR cryostats (models ATP-63G-C and ATP-51G-CF fit the 86/62 and 70/49 cryostats, respectively). ATP-CF probeheads can therefore be used with conventional wide-bore (89mm) SC magnets, either without room-temperature shims (in conjunction with the 86/62 model cryostat) and with room temperature shims (in conjunction with the 70/42 model cryostat).
Features
Probe body is machined from a single piece of highly corrosion-resistant non-magnetic stainless steel tube. The probehead base plate that carries the coil inserts and the goniometer is made of titanium. The high accuracy and low backlash goniometer is machined from Vespel, delivering an exceptional wear resistance and hassle-free performance even at cryogenic temperatures. Stainles-steel ball-bearings are used to seat the trimmer and goniometer vacuum-sealed shafts. The mating shaft adaptors allow for a quick attachment or detachment of the ATM C4G stepper motor unit. When the stepper motor unit is detached from the ATP-CF or not powered, the ATP CF probe, specifically the trimmer and goniometer shafts, can be rotated manually for setup purpuses.
Customizability
Special care has been taken to ensure customizability of the probe, e.g. use of solenoids of various sizes and shapes, easy replacement of trimmer capacitors, and installation of additional mechanical, electrical, and optical components that may be needed in a custom-designed experiment. This is achieved via vacuum sealable access holes in the probe housing with pre-installed vacuum-tight multipole connectors with internal pinning, providing for easy attachment of RF circuits and wiring of external sensors, fiber-optic elements, and power supplies.
Expandability
The use of solder has been reduced to a minimum when assembling the probe parts. Consequently, all mechanical parts can be disassembled using only a screwdriver. For a researcher with engineering skills, this makes it simple to alter the existing parts or to add custom-designed probe parts in order to expand the functionality of the probe. Nevertheless, care has been taken to retain the required level of electromagnetic shielding performance.
Technical specifications
| General | |
|---|---|
| compatibility | for use with Oxford Instruments SpectrostatNMR continuous flow CF‐1200 cryostat |
| max. diameter | φ 61.5 mm (φ 2.42”), model ATP-63G-CF φ 48.8 mm (φ 1.92”), model ATP-51G-CF |
| full length (including shafts) | 30 cm - 120 cm (11.8” to 47.2”), model ATP-63G-CF 30 cm - 60 cm (11.8” to 23.6”), model ATP-51G-CF exact dimensions are to be privided by the customer |
| weight | 3.5 kg (7.7 lbs) at 90 cm (35.4”) length, model ATP-63G-CF 2.5 kg (5.5 lbs) at 50 cm (19.7”) length, model ATP-51G-CF |
| materials | housing: stainless steel, non-magnetic, high corrosion resistance goniometer: Vespel probehead base: titanium |
| temperature range | 4K - 400 K, limited by the operating temperature range of trimmer capacitors |
| trimmer/goniometer adjustment | manual or stepper motor-controlled, mechanical coupling to drive unit via male shaft couplers |
| vacuum sealing | rotary components (shafts): spring loaded bearing seals connectors: gasket seals |
| RF resonant circuit | |
| type | parallel, 2 - 4 trimmer capacitors |
| trimmers | variable trimmer capacitors, standard or cryogenic version, extended shaft 0.5 pF min. capacitance, 70 pF max. capacitance, various capacitance ranges and working voltages available 20 - 105 turns full range max. shaft torque 70 Nmm (10 oz-in) 76 mm (3”) max. length, φ 18 mm (φ 0.7”) max. diameter |
| trimmer mounting | two grounded mounting holes for tuning capacitors two isolated (Teflon or Vespel) mounting holes for matching capacitors |
| trimmer rotational life | 10,000 to 100,000 turns |
| irradiation/detection coil(*) | solenoid, saddle or other shapes rapid exchange coil holders (two pin male plug, Teflon base) for coil soldering φ 20 mm (φ 0.8”) max. sample diameter 30 mm (1”) max. sample length, model ATP-63G-CF 20 mm (0.8”) max. sample length, model ATP-51G-CF |
| coil mounting | female socket, Teflon isolation, fixed into titanium probehead base |
| RF conductor | 2 x semi-rigid, 50 W copper coaxial cables |
| external connectors | 2 x N type female |
| internal connectors to trimmers | 2 x SMA female, replaceable male counterpart with bare rigid cable termination |
| Goniometer | |
| gear ratio | 36:1 (10°/revolution) |
| resolution | 0.02° |
| positioning accuracy | ± 0.1° |
| sample holder seating | hexagonal, with fixing screw |
| max. sample holder dimensions | (*)see coil data above |
| Auxiliary inputs | |
| sensor connector S1 | 5-pin female |
| power connector S2 | 2-pin male, Imax= 4 A, Vmax= 1 kV |
| spare hole | φ 10 mm, vacuum-sealed when not used |