electronic circuit help

need help
ok, i have an 4 bit data encoder, fed to an IR transmitter,
n at the other end, and IR receiver - an amplifier - decoder,

i cannot get back the signal i encoded,
i can get it only when my multimeter +ve probe touches the leg of the receiver, or the leg of the amp output, ...........why ????????
n i m really blur now, can anyone explain ???

Any circuits/diagrams we can look at?

Yes, your question is far too vague.

Are you modulating the IR at 38KHz, and using an IR receiver IC?, if so you need to feed it's 5V supply through a series resistor with a decent sized decoupling capacitor near to the chip.