Hallicrafters-r-274-a-c-d-operation-service-manual-army-tm-11 897 – Service manual (PDF)

Erik from ManualsPlus — Sun, 21 Dec 2025 08:08:10 +0000

The service manual for the Hallicrafters 897 provides detailed instructions for setting up, operating, and troubleshooting the Radio Receivers R-274/FRR, R-274A/FRR, R-274C/FRR, and R-274D/FRR. It includes maintenance procedures such as cleaning and lubricating contacts, using specific compounds and oils, and outlines steps for handling jamming situations to ensure optimal performance.

Brand: Hallicrafters
Model: 897
Type: service manual
File size: 1.1 MB

Manual Overview

The service manual for the Hallicrafters 897, specifically for Radio Receivers R-274/FRR, R-274A/FRR, R-274C/FRR, and R-274D/FRR, provides detailed instructions for maintenance and troubleshooting. The manual emphasizes regular cleaning and lubrication of components such as the Selectivity Switch S1 and the Crystal Phasing Control C161 to ensure optimal performance. Troubleshooting guidance includes varying controls like frequency tuning and selectivity to mitigate jamming effects. The manual specifies the use of specific cleaning compounds and lubricants, cautioning about their flammable and toxic nature. For board-level adjustments, modifications such as the inclusion of an antenna disabling relay in the R-274D/FRR model are highlighted, which protects the antenna coil from high voltage surges. The manual also outlines the need for a 12-volt DC source for certain operations in the D model. Preventive maintenance is recommended monthly, involving visual inspections and necessary tightening and cleaning of components.

Quick Issues Covered

Diagnose power-up failures with antenna disabling relay issues.
Adjust crystal phasing control for optimal signal clarity.
Use schematics for effective circuit tracing and troubleshooting.

Overview

The technical manual covers the Radio Receivers R-274/FRR, R-274A/FRR, R-274C/FRR, and R-274D/FRR. It includes changes and updates to specifications and maintenance procedures, such as cleaning and lubricating components, and provides antijamming procedures. The manual also details differences in models, specifically noting the addition of an antenna disabling relay in the R-274D/FRR model to prevent damage during transmission.