• Country
• United States of America (USA)

• Manufacturer / Brand
• Heathkit (Brand), Heath Co.; Benton Harbor (MI)

• Year
• 1980

• Category
• Service- or Lab Equipment

• Radiomuseum.org ID
• 203607

• • alternative name: Heath Company

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

• Number of Transistors
• Semiconductors present.

• Semiconductors

• Wave bands
• - without

• Power type and voltage
• Alternating Current supply (AC) / 120/240 Volt

• Loudspeaker
• - - No sound reproduction output.

• Material
• Metal case

• from Radiomuseum.org
• Model: Digital-Frequency-Counter IM-2420 / SM-2420 - Heathkit Brand, Heath Co.;

• Shape
• Tablemodel, with any shape - general.

• Dimensions (WHD)
• 254 x 108 x 318 mm / 10 x 4.3 x 12.5 inch

• Notes

• Frequency counter 5 Hz - 512 MHz. In the Period operating mode, the cycle time is measured in seconds; in the Ratio B/A position, the frequency difference between two input frequencies is measured. The proportionally controlled quartz furnace keeps the internal quartz base extremely accurate - 0.1 ppm per year. Four gate opening times enable the desired measurement of UHF signals.

  The kit version of this counter is labeled as Heathkit model IM-2420.  The factory built version is labeled as Heath/Zenith and the model number is SM-2420.   The SM-2420 price in 1980 was $300.

• Net weight (2.2 lb = 1 kg)
• 6.5 lb (6 lb 8 oz) / 2.951 kg

• Price in first year of sale
• 240.00 USD

• Mentioned in
• Heathkit Winter 1981 catalog (copyright 1980)

• Literature/Schematics (1)
• Heath-Zenith ad in Radio-Electronics 12-1980

• Author
• Model page created by Museum Roggenhofer. See "Data change" for further contributors.

• Other Models

• Here you find 715 models, 699 with images and 506 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from Heathkit (Brand), Heath Co.; Benton Harbor (MI)