This general-purpose strip-chart recorder was manufactured by the Sanborn Company between 1935 and 1955. This particular version was configured to allow the simultaneous recording on a strip of paper of two "leads" of the electrocardiogram, but it could also be customized to record other signals such as those related to muscle contraction.
Height: 81 cm
Width: 78 cm
Depth: 38 cm
Manufacturer: Sanborn Company
Model: Recorder model 60-1300
D.C. Amplifier 64-300A
Material: Wood, paper, plastic
Date: c1935-1955
General-purpose strip-chart recorders were manufactured by the Sanborn Company between 1935 and 1955. This particular version was configured to allow the simultaneous recording on a single strip of paper of two "leads" of the electrocardiogram. However, it could also be customized to record other signals, such as those derived from muscle contraction.
Several modules are “plug-ins”, in that they can be easily lifted out of the machine and replaced with a different module serving a different function. This machine has an “ECG PREAMP” module and two “DC AMPLIFIER” modules.
The “ECG PREAMP” module (“ECG” = electrocardiogram, “PREAMP” = “preamplifier”) has two channels (hence the origin of the name “Twin-Viso”), so that one can obtain a simultaneous recording of any two different “leads” of the ECG.
The lead-selector switch (arrows) allows selection of any one of the 12 classic ECG leads: standard limb leads I-II-III, augmented extremity limb leads aVR-aVL-aVF, and chest leads V1-V6. The INSTO control allows recording the ECG trace without having to wait for the machine’s vacuum tubes to warm up, which was important for being able to capture urgent or fleeting cardiac events.
The outputs of the two preamplifiers are sent to the two D. C. AMPLIFIER modules, whose outputs provide a strong enough signal to drive the two pen recorders on the left side of the instrument.
