• Country
• United States of America (USA)

• Manufacturer / Brand
• MFJ Enterprises; Starkville (MS)

• Year
• 1981 ?

• Category
• Amateur Equipment (Other, but not Key)

• Radiomuseum.org ID
• 335102

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

• Number of Transistors
• 5

• Semiconductors
• 40673 2N3904 MPS-A13 2N3904 2N3904

• Wave bands
• Broadcast plus more than 2 Short Wave bands.

• Power type and voltage
• Powered by external power supply or a main unit. / 9-18 Volt

• Loudspeaker
• - - No sound reproduction output.

• Material
• Metal case

• from Radiomuseum.org
• Model: DeLuxe RF Preselector II MFJ-1040B - MFJ Enterprises; Starkville MS

• Shape
• Portable set > 8 inch (also usable without mains)

• Dimensions (WHD)
• 8.25 x 7 x 2.25 inch / 210 x 178 x 57 mm

• Notes

• The MFJ-1040B RF preselector boosts signals from 1.8 to 54 MHz. It utilizes a dual gate MOSFET, and bipolar transistors for low noise and high gain. Gain is up to 20dB.
  Push-button switches are provided for two receivers, two antennas, 20 dB
  attenuator and ON/BYPASS. The band switch selects: 1.8-3, 3-6, 6-15 and 15-54 MHz. Controls are provided for Delay, Gain, Band and Tune.

  Unlike most preselectors which are for receive-only, the MFJ-1040B may be used with a transceiver. Its relay will automatically bypass the RF amplifier when transmitting a signal up to 350 watts PEP input. A push-to-talk connection is also provided as an option.

  Ads note the unit's ability as, "Lets you copy weak, barely readable signals. Rejects out-of band signal images. Strong signal ability reduces cross mod over loading. Excellent signal to noise ratio."  For very strong signals, the 20 dB attenuator switch would be used.

  Rear panel jacks are provided for the use of either RCA phono plugs or PL-259
  connectors for antenna and receiver/ transceiver.  Initially priced at $99.95. Requires a 12 VDC 300ma AC Adapter such an the optional MFJ-1312 power cube sold separately for $7.95. 

  The near-identical earlier model MFJ-1040 was reviewed in Amateur Radio in February 1981.

   

   

• Price in first year of sale
• 99.95 USD

• Mentioned in
• Radio Amateur, February 1981 (MFJ-1040)

• Literature/Schematics (1)
• MFJ-1040B manual

• Author
• Model page created by Rich Post. See "Data change" for further contributors.

• Other Models

• Here you find 67 models, 65 with images and 41 with schematics for wireless sets etc. In French: TSF for Télégraphie sans fil.
  All listed radios etc. from MFJ Enterprises; Starkville (MS)