НовостиNews - ПоискSearch - ТекстыTexts - ФотоPhotos - КартыMaps - СнаряжениеEquipment - LTLT

F4 room, devices, etc.
2019-2024

• Shielded room (11.2019)
• Shelves in the shielded room (09.2020)
• Pump room (10-11.2020)
• Raspberry Pi for pressure measurements (03.2021)
• Installing generators at the back side of the rack (03.2021)
• Gas handling system (03.2021)
• LC filters for magnets (03.2021)
• Femto lock-ins (03.2021)
• Drive boxes (04.2021)
• Top rack (12.2021)
• Fixing Femto lock-ins (11-12.2021)
• Misc (07.2022)
• Adding five more lock-ins, tinyXLR connectors (06-07.2022)
• Final connections of vibrating wires (09.2022)
• Demag power supply
• Misc (03.2023)

Shielded room (11.2019)

New tables and device rack

mounting Tenma power supplies

device rack: grounding bar, power supplies

device rack: Pico oscilloscopes and ADC

first run of the cryostat

13.12.2019, installing computers

connector box for cryostat heaters

Oxford He level meter

I like this wiring

PicoLog ADC24

PicoScope with new grounding

PicoScope with new grounding

Shelves in the shielded room (09.2020)

soldering holders for shelves

flux and grade D solder (Sn/Pb=70/30)

shelves

Pump room (10-11.2020)

1/16" pipe adapters made in the workshop

new Swagelock connectors for N2 traps

exhaust for air pumps

N2 circulation traps

new copper pipes to the traps

pump room

old valves for cooling water

Raspberry Pi for pressure measurements (03.2021)

Installing generators at the back side of the rack (03.2021)

Keysight mounting kit, [dxf]

Gas handling system (03.2021)

bending 6mm pipe

KF to 6mm Swagelock adapters welded in the workshop

new panel for circulation pumps

[dxf]

Room sizes [dxf]

Old connections [dxf]

New connections [dxf]

new location for circulation pumps (roots moved up, rotary under it)

H2 filter installed near circulation traps

N2 trap for 3He sample

cryostat

cryostat flange, thermometer/heater connector box

LC filters for magnets (03.2021)

capacitors

filter box in the cryostat

Femto lock-ins (03.2021)

A small 19" upper rack installed on the cryostat flange. Two blocks (5 lock-ins each) installed, original power supplies removed, output connectors (10 pin Lemo) and power connectors (3 pin XLR) added on back panels.

upper rack with one lock-in block installed

output connector

power wires

PCB and power connector

power extensions

second block installed

Lock-in output is measured with PicoLog ADC24

adapter for ADC

soldering dividers (1:4, 10->2.5V)

lock-in output cables (10 pairs)

ADC in the rack

Drive boxes (04.2021)

Drive box contains input BNC connector, separation transformer 6:1 for separating ground, 100R calibration resistor with BNC connector, current source (0, 1k, 10k, 100k, 1M, inf resistors with switch), 2 output BNC connectors.

Part list

• RS 5173951 RS PRO Black Die Cast Aluminium Enclosure, Shielded, 114.5 x 63.6 x 30.3mm 8.6 10
• RS 2106425 Through Hole Audio Transformer 600 100mW Hz @ 300, 1mW Hz @ 30 12.86 10
• RS 2106469 Transformer Screening Can 5.31 10
• RS 8779874 Grayhill Rotary Switch 12.43 10
• RS 8780240 Grayhill Rotary Switch Knob for use with Encoders, Rotary Switch 2.27 10
• RS 7548770 TE Connectivity 1M Metal Film Resistor 0.25W 0.1% YR1B1M0CC 0.449 15
• RS 8307646 Vishay 100k Metal Film Resistor 0.125W 0.1% PTF56100K00BZEK 1.074 12
• RS 8307422 Vishay 10k Metal Film Resistor 0.125W 0.1% PTF5610K000BYEK 1.223 30
• RS 8306779 Vishay 1k Metal Film Resistor 0.25W 0.1% PTF651K0000BYEK 1.496 12
• RS 8498953 Vishay 100 Metal Film Resistor 0.125W 0.1% PTF56100R00BYEK 1.223 12
• RS 5464910 RS PRO 50 Straight Panel Mount BNC ConnectorBulkhead Fitting, jack 2.526 30
• RS 2843792 RS PRO Male BNC to Male BNC RG58 Coaxial Cable, 50 9.52 15

one of original boxes

new box

new box with fixed 100k resistor

drive boxes in the rack

second ADC unit installed

Top rack (12.2021)

Fixing Femto lock-ins (11-12.2021)

The problem was a huge cross-talk between reference and input. It was even possible to drive wire through the input and measure resonance with fully disconnected drive cables.

The most efficient update was putting aluminium shield on every lock-in module. Also I made new back PCB panels and installed coaxial cables with SMA connectors for input and reference lines between PCB and front panel.

Back PCB:
KiCAD project
Gerber files for ordering

lock-in module

old front panel connection: unexpected connections between lines possible

old back PCB

front panels

metal shield added

new back PCB

modified front panels: BNC feedthroughs for IN, REF, MON; PCB headers for output

front panels connected

output connector

power connector

Misc (07.2022)

multiplexor board

bath heater box ("green connector")

relay for remote control added

Adding five more lock-ins, tinyXLR connectors (06-07.2022)

15 generators

device rack

BNC to tiny XLR adapters for lock-in inputs

soldering tinyXLR to shielded twisted pair

drive cable (15 BNC)

drive and reference cables in the rack

all outputs connected to ADC

15 drive boxes

drive box with added tinyXLR output

new drive box (no BNC output)

drive box with switch

original cryostat connectors removed

upper rack

main rack

Final connections of vibrating wires (09.2022)

Demag power supply

Demag power supply: Cryogenic PS120A.

2019.11.29 - installed in the rack

2023.01.18 - rate control resistor replaced

2023.01 - an additional connector added for parallel connection of an additional power supply before the thermally stabilize shunt resistor. This was really useful for remote current control.

front view

top view

replacing rate control resistor

Misc (03.2023)

replacing batteries in UPS

new panel for magnet wires