For each of the instruments described below I have listed the prices shown in the GR catalogs in my collection.  Catalog O (Jun-1956) and Catalog T (Feb-1968) are online at the BoatAnchor Manual Archive.

The Type 544-B measures resistances from 100 k&Omegs; to 1,000,000 MΩ in five ranges.  Infinite resistance can be distinguished from an unknown of 1 M&Omega.  Test voltages of 100 and 500 V are available from the internal power supply.  Guard connections permit three-terminal measurements.  Bridge balance is indicated on the internal galvanometer.  Accuracy is +/- 3% up to 10,000 M&Omega (first three ranges) and +/- 4% above that point (last two ranges).  I use this instrument to measure capacitor leakage and insulation integrity in the high-voltage stages of radio and TV transmitters.  (Note - my bridge is a Type 544-BS4 - the extra characters indicating that it was manufactured under contract for Western Electric).  Prices (with AC Power Supply) in GR catalogs: L (1948) $295.00, M (Oct-1951) $340.00, N (Jan-1954) $340.00, O (Jun-1956) $355.00, P (Apr-1959) $365.00, Q (May-1961) $415.00, R (May-1963) $450.00.  The Type 544-B manual is online at the BoatAnchor Manual Archive.

This remarkable instrument measures capacitance from 0.05 pf to 1100 μf in seven ranges, and inductance from 0.05 μH to 1100 H in seven ranges.  The series or parallel resistance associated with the component under test can be resolved as resistance from 0.05 mΩ to 1.1 MΩ, or as conductance from 0.05 nmho to 1.1 mho.  The figure of merit (D or Q) can also be measured.  Measurements are made at 1 kHz with the internal oscillator, or from 20 Hz to 20 kHz with an external oscillator.  Basic accuracy for C, G. R and L is ±0.1%.  Prices in GR catalogs: R (May-1963) $1,300.00, S (Jul-1965) $1,300.00, T (Feb-1968) $1,450.00, U (Feb-1970) $1,550.00, 73 (Nov-1972) $1,710.00.  The Type 1608-A manual is online at the BoatAnchor Manual Archive.

This instrument measures inductance from 0.1 nH to 1111 H and associated conductance from 0.1 nmho to 1111 mhos.  Measurements are made with a 1 kHz external oscillator and detector.  Basic accuracy is ±0.1% for inductance and ±1% for conductance.  Prices in GR catalogs: P (Apr-1959) $875.00, Q (May-1961) $950.00, R (May-1963) $950.00, S (Jul-1965) $1,050.00, T (Feb-1968) $1,395.00, U (Feb-1970) $1,600.00, 73 (Nov-1972) $1,735.00.

The effective inductance of a coil or transformer winding can change, depending on the DC and AC currents that it carries.  This change in value is known as incremental inductance.  Conventional AC bridges, which use fairly low levels of AC excitation, cannot measure this change.  An instrument that can must measure the inductance while subjecting the inductor to DC and AC currents similar to those under which the inductor will operate.  The Type 1633-A is such an instrument.  It measures inductance from 20 μH to 10 H.  Associated resistance from 10 mΩ to 1 MΩ is measured as Q.  An external oscillator can be used with the frequency selective internal detector at one of nine frequencies from 50 Hz to 15.75 kHz.  An external detector can be used for any frequency from 20 Hz to 20 kHz.  Basic accuracy is ±1% for inductance and ±2% for resistance.  Up to 7 A RMS of combined DC and AC can be impressed on the sample at up to 1250 V.  With the optional Type 1633-P1 Range-Extension Unit that range can be increased to 50 A.  Suitable AC oscillators and DC bias supplies must provide the voltages and currents needed, and each must be capable of withstanding the currents produced by the other.  Chokes, transformers and filters with ferromagnetic cores can be measured under actual operating conditions.  Nonlinear resistors and the AC impedance of semiconductor junctions can also be measured.  Prices in GR catalogs: R (May-1963) $1,050.00, S (Jul-1965) $1,050.00, T (Feb-1968) $1,395.00, U (Feb-1970) $1,550.00, 73 (Nov-1972) $1,730.00.