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MY little Radio Control page
Video Wireless 2400MHz tiny

Also see the video wireless page if you like. for the normal range bigger stuff

Foreword:
Now wireless video can be put on tiny tiny planes, with this super tiny transmitter

The compleete set I got from rangevideo came with antenna also.


inside the RX


not much to see, it is all integrated into the metal shield case.

this one is frequency stable, no tuning knob !, the 4 channels are selected with a pushbutton
The receiver is supplied with 10-14V DC center pin positive, using a standard 2.1mm DC jack, nice
There is NO reverse polarity protection so bad stuff will happen if you are unlucky with this.
Video and Audio connectors are phono so no need for them adapter cables that always get lost.
The internal circuit is running on 5V from one linear regulator with after my taste a way to little hearsink
with case open I measured 61 C after 10 minutes, and with case closed this will be much more,
I think either give this receiver 9-10V or mount the regulator and hot power resistor so they can transfer their heat to the case


Here the red buttom OLD type, at -96dBm and -98dBm and -100dBm
Sensitivity: -97dB the new type with yellow button (-91dBm with TV signals)
Sensitivity: -96dB the old type with red button (-90dBm with TV signals)
Supply Volt and Current : 12V 214mA

Receiver center frequency: measured with Agilent E4438C 3MHz dev 100kHz sine
     old-type  new-type
CH1   2.412     2.412       
CH2   2.430     2.438
CH3   2.447     2.457
CH4   2.465     2.475

The tiny TX is only 1.9grams and measures 18 x 17 mm.
how to set channels with solder joints, X mean solder joint to ground
A  B  C  D
X  X  X  X 2.410  CH1  
X  X  X    2.411
X  X     X 2.408
X  X       2.414  

X     X  X 2.450  CH3
X     X    2.453
X        X 2.448
X          2.450

   X  X  X 2.430  CH2
   X  X    2.433
   X     X 2.428
   X       2.432  

      X  X 2.470  CH4 (factory default)
      X    2.473
         X 2.468  
 n o n e   2.468  
This transmitter have 16 possible combinations, they generate different TX frequency.
Always change combinations with poweroff.

The adjust trimmer in the top right corner adjust the Audio carrier to 6.5MHz.
This tiny transmitter exist in two types a +5dBm and a +9dBm, they both run on 5V DC
I got the +9dBm type, TX power:
5.5V 39mA +12.0dBm 2.47024
5.0V 34mA +10.8dBm 2.47024
4.5V 30mA +9.6dBm 2.47028
4.0V 26mA +8.2dBm 2.47024
at 3.8V the VCO did not lock, plenty of supply margin, and frequency nice stable

Spurious Harmonics :

2.470 +10dBm fundamental wanted frequency
4.940 -39dBm 2nd
7.416 -47dBm 3rd
9.880 -27dBm 4th quite strong this one
12.350 -42dBm 5th
14.821 -47dBm 6th
17.290 nothing to see, all the way up from here, still nothing.


Here at 5.0V over 10mW of power, nice.


The delta from video to audio is 6.5Mhz and -18dB


the transmitter was soldered to SMA connector, and mounted directly to spectrum analyzer to awoid loss


this transmitter spectrum with a PAL video signal, note the 50MHz span.

the tiny tx datasheet is here

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Thomas Scherrer OZ2CPU Sep 2007