This analog video transmission system on 3.3 GHz band caught my attention a while ago. Was curious how they implemented the system, what decisions used. Bought one system for my self to disassemble. Here I will share some photos, maybe someone will find them interesting.
Main specifications from manufacturers web site:
– Operating Band: 3.3 GHz
– Operating Voltage: 9-17V DC
– Current Max Consumption @12V: 90mA/240mA
– Output Power: 50/200mW (+/- 1dB)
– Camera Voltage: 12 volts (on-board clean switching regulator)
– Camera Max Current: 200 mA
– Nominal output impedance: 50 ohms
– Sub carrier frequency: 6.5 MHz
– FM-FM modulation
– 6.5MHz audio sub-carrier (Stereo).
– SAW Filter Bandwidth: 16 MHz
– RF sensitivity -90dBm (typical).
– Operating Current: <150mA @12V
– Operating Voltage: 5-16 VDC
CH1: 3320 MHz
CH2: 3345 MHz
CH3: 3370 MHz
CH4: 3395 MHz
CH5: 3420 MHz
CH6: 3440 MHz
CH7: 3470 MHz
CH8: 3495 MHz
CH1: 3310 MHz
CH2: 3330 MHz
CH3: 3355 MHz
CH4: 3380 MHz
CH5: 3405 MHz
CH6: 3430 MHz
CH7: 3455 MHz
CH8: 3480 MHz
Transmitter bottom side has some DC/DC converters and PIC12F1840 microcontroller, microphone frontend.
Top side has unidentified main chip, power amplifier chip RF5603 and quite a few discrete components supposedly used in audio/video modulation scheme. I believe that I managed to figure out unidentified chip model number, but that will be discussed in new post.
Receiver top side has RF tuner can, few DC/DC power supplies and other various components that are not so interesting.
The same side but with tuner can removed.
On the bottom side we can find RTC6721 audio demodulator, video amplifier, PIC16F1503 microcontroller.
RF tuner with top side opened here we can find RF signal low noise amplifier, IF SAW filter with 479.50 MHz center frequency, RTC6711 analog video receiver for 2,4Ghz band, LDO voltage regulator.
RF tuner bottom side has unidentified chip and LDO voltage regulator. From the pinout mysterious chip seems to be the same as in transmitter though in different package. Tx – QFN, Rx tuner – VFQFN. More about this chip in future post.