1650-A: Difference between revisions

Latest revision as of 16:35, 4 June 2024

General Radio 1650-A

Portable impedance bridge

Available from 1959 to 1967

Manuals

Catalog History

Document	Year	Page
Catalog P	1959	24
Catalog Q	1961	22
Catalog R	1963	34
Catalog S	1965	50

(All manuals in PDF format unless noted otherwise)

The General Radio 1650-A is a portable impedance bridge introduced in Catalog P (1959). It was succeeded by the 1650-B in Catalog T (1968).

The 1650 was the first GR impedance bridge to feature the "Orthonull" function, which is a mechanical link driving the DQ dial from the CRL dial through a friction clutch. (Conversely, turning the DQ dial will not turn the CRL dial.) It helps avoid the "sliding null" problem when measuring components with high losses.

The 1650-P1 Test Jig accessory was designed for the 1650-A.

Key Specifications

Capacitance: 1 pF to 1100 μF in 7 ranges
Inductance: 1 μH to 1100 H in 7 ranges
Resistance: 1 mΩ to 11 MΩ in 8 ranges, AC or DC
D (of series capacitance): 0.001 to 1 at 1 kHz, (parallel capacitance) 0.1 to 50 at 1 kHz
Q (of series inductance): 0.02 to 10 at 1 kHz, (parallel inductance) 1 to 1000 at 1 kHz
Basic accuracy: ±1% of full scale, ±5% for dissipation factor
Internal oscillator: 1 kHz ±2%
Frequency range: 20 Hz to 20 kHz (to 100 kHz with reduced accuracy)
DC Supply: 6 V, max. 60 mA; Battery: Four D cells, current drain 10 mA (AC measurements)
External Oscillator and Detector: Type 1210-C Unit R-C Oscillator, Type 1311-A Audio Oscillator and Type 1232-A Tuned Amplifier and Null Detector are recommended for audio measurements at frequencies other than 1 kHz
DC Polarization: 600 V may be applied (from external source) for series capacitance measurements
Weight: 17 pounds (8 kg) net

Links

The GR 1650-A & 1650-B Portable Bridges @ conradhoffman.com
US Patent 2872639, Henry P Hall, Electrical bridge and method. Filed Oct. 10, 1956; Granted Feb. 3, 1959 (describing the Orthonull feature)
US Patent 2966257, Henry C Littlejohn, Instrument carrying case. Filed Nov. 5, 1959; Granted Dec. 27, 1960
Henry P. Hall, A New Universal Impedance Bridge. General Radio Experimenter Volume 33, No. 3, March 1959, page 3.
Henry P. Hall, Orthonull - A Mechanical Device to Improve Bridge Balance Convergence. General Radio Experimenter Volume 33, No. 4, April 1959, page 7.
IET Labs Application Note, Henry Hall: Father of the Digibridge

Videos

Pictures

Internal

Internal view. The red jack on the bottom left is an aftermarket modification on this unit for an external +6 V supply.

@@ Line 1: / Line 1: @@
-The '''General Radio 1650A''' is a portable impedance bridge introduced in 1959.
+{{GR Product
+|model=1650-A
+|codes=BATON,1650-9701,1650-9540,1650-9570
+|class=impedance measurement
+|summary=Portable impedance bridge
+|image=Gr 1650-a 1.jpeg
+|caption=Genrad 1650-A Bridge
+|series=
+|introduced=1959
+|discontinued=1967
+|designers=Henry P. Hall
+|manuals=
+* [[Media:GR 1650-A Impedance Bridge Manual (1964).pdf|General Radio 1650-A Impedance Bridge Manual, 1964 version]] (OCRed)
+* [[Media:GR 1650-A Impedance Bridge Manual (1960).pdf|General Radio 1650-A Impedance Bridge Manual, 1960 version]] (OCRed)
+{{Catalog History}}
+}}
+The {{Title|General Radio 1650-A}} is a portable impedance bridge introduced in {{Catalog P}}.  It was succeeded by the [[1650-B]] in {{Catalog T}}.
-==Manuals==
+The 1650 was the first GR impedance bridge to feature the "Orthonull" function, which is a mechanical link driving the DQ dial from the CRL dial through a friction clutch.  (Conversely, turning the DQ dial will ''not'' turn the CRL dial.)
-* [https://bama.edebris.com/download/gr/1650a/GR%201650-A%20Impedance%20Bridge.pdf GR 1650-A manual] @ BAMA
+It helps avoid the "sliding null" problem when measuring components with high losses.
+The [[1650-P1|1650-P1 Test Jig]] accessory was designed for the 1650-A.
+==Key Specifications==
+* Capacitance: 1 pF to 1100 μF in 7 ranges
+* Inductance: 1 μH to 1100 H in 7 ranges
+* Resistance: 1 mΩ to 11 MΩ in 8 ranges, AC or DC
+* D (of series capacitance): 0.001 to 1 at 1 kHz, (parallel capacitance) 0.1 to 50 at 1 kHz
+* Q (of series inductance): 0.02 to 10 at 1 kHz, (parallel inductance) 1 to 1000 at 1 kHz
+* Basic accuracy: ±1% of full scale, ±5% for dissipation factor
+* Internal oscillator: 1 kHz ±2%
+* Frequency range: 20 Hz to 20 kHz (to 100 kHz with reduced accuracy)
+* DC Supply: 6 V, max. 60 mA; Battery: Four D cells, current drain 10 mA (AC measurements)
+* External Oscillator and Detector: [[1210-C|Type 1210-C Unit R-C Oscillator]], [[1311-A|Type 1311-A Audio Oscillator]] and [[1232-A|Type 1232-A Tuned Amplifier and Null Detector]] are recommended for audio measurements at frequencies other than 1 kHz
+* DC Polarization: 600 V may be applied (from external source) for series capacitance measurements
+* Weight: 17 pounds (8 kg) net
 ==Links==
 * [https://conradhoffman.com/GR1650.htm The GR 1650-A & 1650-B Portable Bridges] @ conradhoffman.com
+* [https://patents.google.com/patent/US2872639A/en US Patent 2872639, Henry P Hall, ''Electrical bridge and method'']. Filed Oct. 10, 1956; Granted Feb. 3, 1959 (describing the Orthonull feature)
+* [https://patents.google.com/patent/US2966257A/en US Patent 2966257, Henry C Littlejohn, ''Instrument carrying case'']. Filed Nov. 5, 1959; Granted Dec. 27, 1960
+* [[Henry P. Hall]], ''A New Universal Impedance Bridge''. [[Media:General Radio Experimenter Vol.33 No.3 March 1959.pdf|General Radio Experimenter Volume 33, No. 3, March 1959]], page 3.
+* [[Henry P. Hall]], ''Orthonull - A Mechanical Device to Improve Bridge Balance Convergence''. [[Media:General Radio Experimenter Vol.33 No.4 April 1959.pdf|General Radio Experimenter Volume 33, No. 4, April 1959]], page 7.
+* [https://www.ietlabs.com/pdf/application_notes/12-Henry%20Hall%20Digibridge%20Patent-Digibridge.pdf IET Labs Application Note, ''Henry Hall: Father of the Digibridge'']
+===Videos===
+* [https://www.youtube.com/watch?v=Id9wMgjEQ04 General Radio Genrad 1650 impedance bridge - Oscillator Circuit repair and calibration] @ YouTube
+* [https://www.youtube.com/watch?v=VMFOWfUiLLw General Radio 1650-A Experimentation with Coils Capacitors and Tank circuits] @ YouTube
+* [https://www.youtube.com/watch?v=96G_VjkvvnE Vacuum Tube Audio Transformer Impedance Determined With General Radio Impedance Bridge] @ YouTube
 ==Pictures==
@@ Line 18: / Line 60: @@
 ===Internal===
 <gallery>
-GR 1650-A internal 1.jpg
+GR 1650-A internal 1.jpg | Internal view. The red jack on the bottom left is an aftermarket modification on this unit for an external +6 V supply.
 GR 1650-A internal 2.jpg
 GR 1650-A internal 3.jpg
@@ Line 31: / Line 73: @@
 [[Category:Impedance measurement]]
 [[Category:Introduced in 1959]]
+__NOTOC__