IR receiver for J2 connector
This circuit provides an IR-Receiver for the internal connector J2 on the Technotrend
DVB-s Rev. 1.3, 1.5 and 1.6. It works with the DVB driver and lirc or the remote
plugin, the Technotrend software, etc. You have to use a RC5 remote control.
How it works: The circuit inverts the signal of the TSOP. With/without a 38 kHz signal, the IR output of the TSOP is low (0 V)/high (5 V), as well the gate of the FET transistor, so the drain is high/low, as pin 9 has a pullup resistor on the DVBs card.
For debugging your circuit with a simple voltmeter: Pressing a button on the hauppauge (or any other RC5) RC, you get 0.6-0.7V at pin 9, without 0.3V.
BS170 , TSOP1738
Note: the IR receiver doesn't work if a CI is connected to same card.
Since October 2002 the DVB driver is capable of processing non inverted signals, so the TSOP can be connected directly to the J2. RCMM remotes are now supported as well.
The resistors and the capacitor are there for safety, they can be omitted.
Rev. 2.1 and 2.2 cards have a mini RCA plug (Miniklinkenbuchse) for IR-receiver connection. The layout is:
Basis -- GND
Ring -- IR
Tip -- VCC
Both circuits can be used, just replace the J2 connector with a mini RCA jack.