The pic show the TR1001 868.35 MHz Hybrid Transceiver. The circuit is soldered up-side-down. TR1001 868.35 MHz Hybrid Transceiver.
Do you need short-range wireless communication.
This project explain how you can use the TR1001.
Speed can be up to 115.2 kbps.
High sensitivity and few external components.
All contribution to this page are most welcome!

To build wireless communication can sometime be quit difficult and you need lot of components.
This transceiver handles it all for you and makes life almost to simple.
All you need to do is to hook up some external components and you have a high speed communication unit.

  • Operating Frequency : 868.35 MHz
  • Sensitivity, 2.4 kbps : -106 dBm
  • Sensitivity, 19.2 kbps : -101 dBm
  • Modulation Types : OOK & ASK
  • Power Supply : 0-4V
  • Small size
  • Only 2 inductors, no tuning
  • Transmitting range 100m

  • Hardware and schematic
    This is my experimenting receiver unit.
    There is not much I can write here. The schematic speaks for itself.
    The schematic above is built from the datasheet and works with 2.4 kbps.
    The transmitting range was about 100m.

    Amplifier 1:
    This picture show a TR1001 based on 2 transistors.
    Here is a schematic of a simple amplifier I built to my TR1001.
    The output power was +15dBm and I had strong signal at 100m range.

    Amplifier 2:
    This schematic show a simple amplifier for TR1001 based on MMIC and a transistor.
    The output power was more than 15dBm and I had very strong signal at 100m range.
    I am sure there are many other ways to build PA and I will come back to this and update this page with more examples.

    Amplifier 3:

    My experiment board
    The pic show my experiment board of the TR1001. I also made a small amplifier based on 2 transistors.
    Here is a photo of my experiment board.
    You can see the two inductors and the antenna to the right.

    There is a few things you should know about the TR1001 circuit.
    The data output (pin 7) only deliver low current, so you must not load it down to much.
    I used a speaker to listen to the signal, but it loaded the output to much so I barley heard the data pulses.
    Best way is to connect the data output (pin 7), to a digital circuit or a processor.

    There is 3 data rate mode you can use.
    OOK = 2400 bps
    OOK = 19200 bps
    ASK = 115.200 bps

    Each data rate has a Minimum signal Pulse and a Maximum signal Pulse. From the datasheet you can read all details.
    If you stay withing in this speed you will have no problem with serial communication.

    The circuit has pads under the case (not on the side), so it is a bit tricky to solder directly to PCB.
    I really advice you to place the circuit up side down and connect the pads with thin wire to the PCB.
    This soldering ways is simple to do, and much safer. You can be sure that all pads has been connected.
    Photo above show my first soldering directly to the PCB..and it was a bit tricky. The photo at top of the page show how I solder the circuit up side down.

    AV sender using QAM soundcard modem
    The TR1001 is perfect to use for sending audio and video.
    Take a look at this great software made by Jonti.

    AV Rs232 Sender
    J-QAM, A QAM soundcard modem

    tr1001.pdf datasheet for tr1001.pdf

    Transmitting distance at 900 MHz
    To demonstrate the basic difference in wave propagation of 900 MHz, a quick look at path loss is provided.
    As waves propagate out from the transmitter, some attenuation of the signal takes place due to properties of the medium (air in most cases).
    Path loss describes this attenuation as a function of the wavelength of the operating frequency and the distance between the transmitter and receiver.

    Path loss is derived from the Friis transmission equation and is defined as:

    Path Loss = 20 log(4*p*r/λ) dB

    where r is the distance between the transmitter and receiver, and λ is the wavelength .
    900 MHz transmitters (λ=0.33 meters).

    The path loss equation represents path loss (signal attenuation) as a function of distance between the receiver and transmitter and the wavelength of the operating frequency.
    This equation is derived from the Friis transmission equation and is given by:

    Path Loss = 20* log(4*p*r/λ) dB (Eq. 1), where
    r = distance between transmitter and receiver
    λ = wavelength

    The Friis transmission equation can be used to represent the path loss as the sum of the other system factors leading to the following equation:

    Path Loss = P(t) + G(t) + G(r) - R(s) - F(s) dB (Eq. 2), where
    P(t) = transmitted power
    G(t) = gain of transmit antenna
    G(r) = gain of receive antenna
    R(s) = sensitivity of receiver
    F(s) = fading margin, (experimentally determined to be 22dBm)

    These two equations can be used to calculate the maximum range of RF modules.

    1. Consider the range of 1W RF module:

      = 0.33 meters (for f=900 MHz)

      (Eq. 1) Path Loss = 122 dB = 20 * log(4*π*r/λ)
      (Eq. 2) Path Loss = 30dBm + 2dB + 2dB - (-110dBm) - 22dBm= 122 dB

      This give r = 33 km = 20 miles transmitting range.

    2. Consider the range of 18W RF module:

      This give r = 133 km = 82 miles transmitting range.

    Final word
    In this part, I describes a very powerful transceiver circuit with few external components.
    It can handle all kinds of communication and with an impressive speed of 115.2 kbps.
    If you wish to order your own TR1001 or 38H15, you can find it at the component page

    You can always mail me if there is anything unclear.
    I wish you good luck with your projects and thanks for visit my page.

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    Copyright © Last modified on 13 Mars 2007.