GB1487101A - Apparatus for measuring a variable impedance such as liquid conductivity - Google Patents
Apparatus for measuring a variable impedance such as liquid conductivityInfo
- Publication number
- GB1487101A GB1487101A GB2123174A GB2123174A GB1487101A GB 1487101 A GB1487101 A GB 1487101A GB 2123174 A GB2123174 A GB 2123174A GB 2123174 A GB2123174 A GB 2123174A GB 1487101 A GB1487101 A GB 1487101A
- Authority
- GB
- United Kingdom
- Prior art keywords
- change
- cell
- oscillator
- voltage
- transistor
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R27/00—Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
- G01R27/02—Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
- G01R27/22—Measuring resistance of fluids
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
1487101 Resistance measuring bridges A F MILLS 3 Oct 1974 [14 May 1974 2 Oct 1974] 21231/74 and 42824/74 Heading G1U For measuring a variable impedance, a transformer applies an output signal from a relaxation oscillator to the impedance, any change in the impedance causing a change in the signal which is detected. The arrangement is used to measure the concentration of a detergent solution. The four arms of a bridge are composed respectively of R6; R7; C2 in parallel with R5 ; primary winding of T 1 in series with the collector-emitter junction of Tr2. A conductivity cell 1 is connected across the secondary winding of T1. A relaxation oscillator comprised of capacitor C1 charging via resistor R1 and discharging through a programmable unijunction transistor Tr 1 has its output frequency and amplitude determined by R3 and RV1 with a diode D1 providing temperature compensation. The oscillator output pulses 5 are fed to the transistor Tr2 which thus supplies an approximate squarewave voltage to the cell 1. C 2 and R 5 stabilize the voltage at the transistor emitter and this is compared with the reference voltage at the junction of R6 and R7 by a meter M1. The arrangement is calibrated by inserting the cell in a solution of known concentration and adjusting RV1 to give centre-scale deflection (about 25ÁA) on M1. Any change in the cell 1 resistance due to change in conductivity of the detergent solution causes a change in the collector load of Tr2 and thus a change in emitter voltage. Also, the change in collector load is reflected through the transistor appearing as a change in the oscillator load, which affects the oscillator frequency and amplitude, accentuating the change in emitter voltage. The battery supply may be tested by closing PB1 when S1 is "OFF".
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2123174A GB1487101A (en) | 1974-10-03 | 1974-10-03 | Apparatus for measuring a variable impedance such as liquid conductivity |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB2123174A GB1487101A (en) | 1974-10-03 | 1974-10-03 | Apparatus for measuring a variable impedance such as liquid conductivity |
Publications (1)
Publication Number | Publication Date |
---|---|
GB1487101A true GB1487101A (en) | 1977-09-28 |
Family
ID=10159407
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB2123174A Expired GB1487101A (en) | 1974-10-03 | 1974-10-03 | Apparatus for measuring a variable impedance such as liquid conductivity |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB1487101A (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010051313A1 (en) * | 2008-10-30 | 2010-05-06 | Bose Corporation | Impedance measurement system and method |
US9610579B2 (en) | 2014-01-07 | 2017-04-04 | Daktari Diagnostics, Inc. | Fluid delivery devices, systems, and methods |
-
1974
- 1974-10-03 GB GB2123174A patent/GB1487101A/en not_active Expired
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2010051313A1 (en) * | 2008-10-30 | 2010-05-06 | Bose Corporation | Impedance measurement system and method |
EP2350632A1 (en) * | 2008-10-30 | 2011-08-03 | Bose Corporation | Impedance measurement system and method |
US8242792B2 (en) | 2008-10-30 | 2012-08-14 | Bose Corporation | Impedance measurement system and method |
EP2350632A4 (en) * | 2008-10-30 | 2014-05-07 | Bose Corp | Impedance measurement system and method |
AP3683A (en) * | 2008-10-30 | 2016-04-23 | Bose Corp | Impedance measurement system and method |
US9610579B2 (en) | 2014-01-07 | 2017-04-04 | Daktari Diagnostics, Inc. | Fluid delivery devices, systems, and methods |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
GB1463880A (en) | Apparatus for conductivity measurements | |
GB1487101A (en) | Apparatus for measuring a variable impedance such as liquid conductivity | |
GB680311A (en) | Improvements in or relating to apparatus for the measurement of peak strain | |
GB1070081A (en) | Improvements in or relating to apparatus for the direct measurement of capacitance | |
GB1221072A (en) | Capacitive measurement of the level of material in a container | |
JPS568563A (en) | Measuring device for reactance change | |
JPS5856803B2 (en) | Yuden Taibutsupin O Kensasuru Hohou Oyobi Souchi | |
GB1083526A (en) | Apparatus for measuring the reverse recovery charge of fast semiconductor diodes | |
SU109639A1 (en) | Compensation method for measuring pulse amplitude | |
US3588692A (en) | Circuit for developing a pulse having an amplitude determined by the capacitance of a capacitor coupled thereto | |
SU96261A1 (en) | Device for calibration of nonlinear distortion meters | |
SU90574A1 (en) | ||
SU73666A1 (en) | Device for measuring the loss tangent | |
SU1401289A1 (en) | Device for measuring weight of loose materials | |
SU834400A1 (en) | Electromagnetic flowmeter | |
SU654889A1 (en) | Method of measuring dielectric parameters of materials | |
SU1509756A1 (en) | Method of measuring duration of pulses of periodic pulse sequence | |
SU96063A1 (en) | Device for measuring welding time | |
SU619894A1 (en) | Time interval meter | |
SU104825A1 (en) | Method for measuring small alternating currents and voltages compensation methods | |
SU113473A1 (en) | Instrument for determining the thickness of metal products from the surface | |
SU105638A1 (en) | Compensation device | |
SU1111031A1 (en) | Resonance-type level indicator | |
SU378928A1 (en) | METHOD OF SIMULTANEOUS MEASUREMENT OF PARAMETERS | |
GB783456A (en) | Improvements in or relating to arrangements for determining network insertion loss |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PS | Patent sealed | ||
PCNP | Patent ceased through non-payment of renewal fee |