Sorry for the repeat post, but the Piclist Nazis tell me my header was
incorrect, so I'll try again...  (they'll be checking for grammer and
punctuation pretty soon :-)

   I am playing with those $10 receiver/transmitters from techamerica
(900-6985 & 900-6986).  I can't seem to get them to work that well.
   I have both the rx and tx on the same board with a pushbutton
connected to the codein:  open=grounded, closed=4.7Kpullup resistor.
   Power is a 9v battery feeding a 7805.
   I push the button, and a fraction of a second later the led on the
rx's digital-out goes on, let go and it goes off.  The voltage on that
pin is only 3.7v, instead of the 5v I would have expected.  The
linear-out seems to have a 2v output for low and jumps to 2.3v for high
but returns even when the input is held high.
   The problem is that it flickers when it's first turned on and
frequently stays high.  And if I touch the board or the antennas, the
led flickers.  I don't see where I've missed any grounds.  Shouldn't the
carrier and decoder eliminate that sort of nonsense?
   Secondly, if I move the receiver circuit to a separate board, then it
receives absolutely nothing.
   The antennas are just 4 inch pieces of circuit jumper wire, but
should be more than sufficient for the 6" of air I am trying to span.  I

tried connecting the rfout to the rfin directly, with the same results.
   I only have a 100Mhz scope, and I am baffled by the talk of
diode-decouplers and what not.
   This is my first adventure into radio so any help would be extremely
appreciated.

   Greg Hartung

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