On 8/9/2011 9:45 AM, Dan Smith wrote:
On 8/9/2011 12:49 AM, Ron McKenzie wrote:
[...] Some questions to help increase my knowledge of current practices: [...] 2. Is a repeater operator precluded from selecting different CTSS or DTCCS codes for Rx and Tx?
Yes, at the moment.
Err, perhaps repeater operator is a bit ambiguous here?
The repeater owner/administrator, who configures the repeater can can set up a repeater with different tone or digital squelcn settings for transmit / receive. The occurrences of this are pretty rare, and a number of popular radios do not support the setting of different squelch encoding / decoding on the same memory channel. However, I've seen a couple of popular linked repeater systems in the NYC area move to this configuration to avoid interference.
Also, I'm going to take the risk of being a bit pedantic here since I've seen a lot of misunderstanding on different mailing lists.
CTCSS, Aka Tone Squelch, or PL (Private Line) is a method for including an analog tone in a transmitted signal in order to allow the receiver to operated in a mode where it will only open the squelch if the tone is present. This prevents noise or even other undesired signals from being heard.
DCS, Digital Coded Squelch, uses a digital code embedded in the transmitted signal that provides for more possible squelch codes and greater reduction in an unwanted signal opening the receiver's squelch.
The typical repeater setup (especially in the US) is that the repeater's receiver has a tone squelch setup to prevent the repeater from keying up on unwanted noise or signals. This means that in order to use the repeater, your radio must *encode* the squelch tone in your transmission.
The repeater when retransmitting a signal may encode a squelch tone or digital code. This is a feature for the convenience of the people who listen to repeater to provided added protection against hearing unwanted noise or signals. None of the receive squelch settings on your end are required to use the repeater and if set incorrectly can prevent you from hearing the repeater. Given that it is often best to make sure you've got the settings for the repeater working correctly before you enable any receive squelch settings for that memory. If you don't live in a noisy area you could skip that step entirely.
About half of the repeaters that I've come across do transmit tone squelch which makes monitoring and scanning that much more pleasant. I've only come across three repeaters in my area so far that use DCS.
The most of the non-typical setups I've seen are from linked repeater systems in areas that are densely packed with radios.
Hope This Helps, --Rob