[Asterisk-Users] T1 Line install.. (UK Muppet)

[Andrew Kohlsmith]

> The robbed bit T1 has 2 signalling bits, but the usually do the same
> thing, so its really like having just one signalling bit. However, the
> timing of changes to that signalling bit can follow one of several
> patterns. You will see the terms immediate start and delayed dial used,
> as well as the terms LS, GS, etc. These are more descriptive, as they
> describe what will actually happen to the signalling bit.

Hmmm...  I'd worked with T1s where the signalling bits (6th, 12th, 18th and 
24th DS0 LSBs) formed a 2- or 4-bit word which described the channel state -- 
Which signalling type is that?  

I had no idea that the robbed bits (still every 6th frame?) were used to 
recreate the analog-side signalling to that kind of extent.  

> Other variants are that only signalling bit A or only bit B changes; the
> signalling bits are inverted; the line only works during a full moon; etc.

How is reverse-battery (kewlstart) signalled?  Actually do you have any 
resources I could devour now that I've had this taste?  

Thank you for taking the time to explain this.  I thought that the signal bits 
were standardized...  Of course it works out that like most other things in 
technology, there are many standards to choose from.  :-)

Regards,
Andrew