Short Wave Dual Conversion R-9710

Tecsun 德生通用电器制造有限公司 Tecsun General Electric Manufacturing Co., Ltd; Dongguan (Guangdong, SC)

Data
Forum
Pictures
Collections

  • Year
  • 2002 ?
  • Category
  • Broadcast Receiver - or past WW2 Tuner
  • Radiomuseum.org ID
  • 327762

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

 Technical Specifications

  • Number of Transistors
  • 8
  • Main principle
  • Superhet, double/triple conversion
  • Wave bands
  • Broadcast, more than 2 SW bands plus FM or UHF.
  • Power type and voltage
  • Batteries / addl. power jack / AA: 2 x 1.5 / DC 3 Volt
  • Loudspeaker
  • Permanent Magnet Dynamic (PDyn) Loudspeaker (moving coil) / Ø 4.5 cm = 1.8 inch
  • Power out
  • 0.15 W (unknown quality)
  • Material
  • Plastics (no bakelite or catalin)
  • from Radiomuseum.org
  • Model: Short Wave Dual Conversion R-9710 - Tecsun 德生通用电器制造有限公...
  • Shape
  • Very small Portable or Pocket-Set (Handheld) < 8 inch.
  • Dimensions (WHD)
  • 118 x 75 x 29 mm / 4.6 x 3 x 1.1 inch
  • Notes

  • The Tecsun R-9710 is a small portable analog radio offering FM stereo (when listening with earphones), MW (AM), and eight SW bands featuring dual conversion where the first discrete local oscillator uses eight crystals for improved stability, one per SW band.

    Frequency coverage

    • FM: 87 - 108 MHz (IF: 10.7 MHz)
    • MW: 525 - 1710 kHz (IF: 455 kHz)
    • SW: 5.95 - 21.85 MHz (1st IF: 10.7 MHz; 2nd IF: 455 kHz)
      • SW1: 5.90 - 6.20 MHz
      • SW2: 7.10 - 7.30 MHz
      • SW3: 9.50 - 9.90 MHz
      • SW4: 11.65 - 12.05 MHz
      • SW5: 13.60 - 13.80 MHz
      • SW6: 15.10 - 15.60 MHz
      • SW7: 17.55 - 17.90 MHz
      • SW8: 21.45 - 21.85 MHz

    Sensitivity

    • FM: <10 uV
    • AM: <1 mV/m
    • SW: <30 uV

    Selectivity: >20dB

    Included accessories

    • Stereo earphones
    • Carrying pouch
    • External FM/SW soft antenna (13 ft)
    • English manual

    Some technical details

    The design is built around the TA2111F AM/FM radio tuner IC1 and the CXA1622M dual channel audio power amp IC2.

    The MW band uses a large antenna ferrite bar to improve the reception, as it is connected to the TA2111F AM RF input without front-end amplification.

    The FM band uses a 2SC9014 Si transistor VT8 and a LC band pass filter L1/C4 as RF front-end to improve the reception.

    The SW bands uses a 2SK544 FET VT2 as RF front-end/mixer where the 1st local oscillator is handled by a 2SC9018 VT5 and 8 x Crystals, one per band. The 1st IF runs at 10.7MHz and is passed thru T1 transformer to be amplified by a 2SC9018 VT1 and then passed to the IC1 via CF3 10.7 MHz ceramic filter.

    The radio can operate from a external 3V DC power adapter using a 3.5mm jack, where the positive pole is on the outside and negative pole on the center. To protect the internal  components against inadequate or malfunctioning power adapters, one 1N4737 7.5V 1 Watt Zenner diode VD6 is configured in parallel with the Vcc line.

  • Price in first year of sale
  • 24.00 USD
  • Author
  • Model page created by Didier Tholomier. See "Data change" for further contributors.

 Collections | Museums | Literature

Collections

The model Short Wave Dual Conversion is part of the collections of the following members.

 Forum

Forum contributions about this model: Tecsun 德生通用电器...: Short Wave Dual Conversion R-9710

Threads: 1 | Posts: 1

In my Tecsun R-9710 with PCB Rev. R-9710V13 with production date of 2014.10.20, the indicated integrated circuits in the schematic diagram have been replaced with Chinese equivalents, as follows:

Component Original schematic diagram R-9710V13 2014.10.20 production
IC1 Toshiba TA2111F Silan SA2111CB
IC2 Sony CXA1622M Huajing CD1622CB

 

Jose Mesquita, 04.Nov.21

Weitere Posts (1) zu diesem Thema.