I haven't used one of those, but I'd ask, what is it doing differently?
If you invert the phase of the tone 180 degrees (or 120 for some older
motorolas), it should mute correctly. The only issues I've ever run into
is either the transmit delay is too short (ie, TK-x05D series), and the
rx squelch doesn't have time to close all the way, or it's too long and
the rx squelch closes, then opens back up again before the tx goes off
the air. Or the decoder just plain old doesn't recognize it (most ham
rigs). The worst is the VX-1R that, once it decodes the right CTCSS
tone, it stays open until the signal goes away. If you drop tone, it'll
stay open indefinitely, until you drop carrier.
--
Jim Barbour
WD8CHL
skipp025 wrote:
Re: Reverse Burst Comments (Com Spec RB-1)
If you add a circuit like the Com Spec RB-1 board to the typical
repeater system using a ts-32/ts-54 board... the tx ctcss is not
disabled or removed before the RB-1 delayed ptt line drops.
So you have the phase inverted ctcss present for at most up to
200 ms typical before the tx drop. If you don't remove the ctcss
source the inverted ctcss remains up until the tx off/drop...
Any of you actually running the RB-1 board with a true reverse
burst type ctcss decoder (built into your radio)? Is a true
reverse burst decoder in your commercial radio completely fooled
by the phase inverted ctcss before carrier drop function.
Or do you actually still hear some minor difference from the
rb-1 type operation vs an original true Motorhead (Motorola)
encoder - decoder operation?
Thinking out-loud about having to possibly mute the ctcss at some
time after invert and before the delayed ptt drop as a requirement
to get the full/true reverse burst quiet squelch close.
Any of you been down that road already?
skipp
