• Country
• United States of America (USA)

• Manufacturer / Brand
• National Radio Institute (NRI); Washington, DC

• Year
• 1947 ?

• Category
• Service- or Lab Equipment

• Radiomuseum.org ID
• 120371

Click on the schematic thumbnail to request the schematic as a free document.

• Number of Tubes
• 6

• Valves / Tubes
• 6SK7 6SK7 6K6G 6SQ7 6E5 5Y3G

• Main principle
• TRF (Tuned-Radio-Frequency but use of regeneration unknown); 2 AF stage(s)

• Wave bands
• - without

• Power type and voltage
• Alternating Current supply (AC) / 110 - 120 Volt

• Loudspeaker
• Electro Magnetic Dynamic LS (moving-coil with field excitation coil) / Ø 5 inch = 12.7 cm

• Material
• Metal case

• from Radiomuseum.org
• Model: Signal Tracer 33 - National Radio Institute NRI;

• Shape
• Tablemodel, slant panel.

• Dimensions (WHD)
• 12 x 10.25 x 8.25 inch / 305 x 260 x 210 mm

• Notes

• Covers 170 kHz to 11,3 MHz in four ranges.
  Band A: 170 - 490 kHz
  Band B: 490 - 1470 kHz
  Band C: 1470 kHz - 3.9 MHz
  Band D: 3.8 - 11.3 MHz

  Advertised in NRI National Radio News Oct - Nov  1948.

  Input probe capacitance only 2pF.

  Maroon crackle finish.

• Net weight (2.2 lb = 1 kg)
• 15 lb (15 lb 0 oz) / 6.810 kg

• Price in first year of sale
• 52.00 USD

• Literature/Schematics (1)
• -- Original-techn. papers.

• Author
• Model page created by a member from A. See "Data change" for further contributors.

• Other Models

• Here you find 20 models, 20 with images and 8 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from National Radio Institute (NRI); Washington, DC