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MY little Radio Control page
Video Wireless 2400MHz tiny system from IF

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

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

Here is the compleete tiny set, antenna was included, got this tiny set from intelligentflight.com

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

The 4 channels are selected with a pushbutton, and indicated on four LED's
The receiver is supplied with 10-12V 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
so the receiver will run fine from 8-10V, dont give it over 12V, the internal regulator will be too hot then

Supply Volt and Current : 12V 165mA
so this new and improved receiver uses even less current compared to the older versions.

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

Harmonics found at GHz:
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 almost 20mW of power, really nice.

The delta from video to audio is 6.5Mhz and -14dB

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

Video frequency response: 270Hz to 2.8MHz (that is due to the transmitter)
Audio frequency response: 150Hz to 3khz
Audio input max 600mVPP = 4VPP out of receiver, inverted.

50MHz span, no input modulation.

50MHz span, video input, note the amplityde flicker constantly, this is normal

50MHz span, video input, avarage on, note the power is now spread out over a much wider frequency area.


Thomas Scherrer OZ2CPU March 2008