On (26 Feb 97) TONY SZABLOWSKI wrote to DAVID LAWSON...
-> Im setting up a simplex repeater on Lookout Mt 10 miles s-sw of
 TS> Dave, could you please explain how a simplex repeater works?
I'm not Dave....but the way it "works" is with a buffer (a digital voice
recorder) that stores, then "repeats", what the repeater "hears",
*following* what has been said, on the same frequency. This "repeat"
follows after it can no longer detect a carrier (usually when you stop
transmitting). A regular repeater *simultaneously* "repeats" on the
output frequency what is being heard on the input frequency.
It is a little disconcerting to use a simplex repeater because whatever
*you* just said is "repeated" immediately following the end of your
transmission. *You* hear a "repeat" of what you just said. And if you
are in "direct" range of the person you are talking to, you first hear
his direct transmission, followed by a repeat of it. If you are
*almost* in direct range, you hear parts of his transmissions on
direct, and all his transmission when it is repeated. If you cannot hear
the other party on direct at all you have to wait until he has completed
his transmission before you hear anything. In the latter case, you begin
to wonder "where he went" if he makes a long transmission. As a result
of all this, you pretty quickly learn to make your own transmissions
pretty short!
This gets worse if you are at a fixed station and the mobile station you
are talking to is getting out of range of the repeater but getting
closer to you as he drives along. In that case, you might hear all of
what he is saying on direct, but the repeater does not. The repeater
might come on and repeat *parts* of what he said, while he is still
transmitting, because it (the repeater) thinks he has quit talking part
of the time (it no longer detects a "carrier"). Or...you might be in a
mobile aproching both the other mobile *and* the repeater, while he is
aproching you, but going away from the repeater!
Works just like packet radio except when using packet your TNC decides
when to "transmit" based on the buffer size it holds before it
(the TNC) turns on your transmitter to send the packet, while you
maybe/are still typing. And of course most folks using packet radio
don't even hear the repeated packet at all, because they have their
speaker muted/disconnected. Further, your TNC "listens to" a "repeat" of
the packet it just sent coming back from the TNC it sent the packet to,
and if there are errors, it keeps on resending some number of times (up
to about 10) until it is sure the packet has been received properly
before it sends the next (following) packet. The simplex repeater only
sends what it has recorded, one time.
... Corn oil is made from corn. What's baby oil made from?
--- PPoint 2.00
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