[Asterisk-Users] Intel 536ep as a FXO?

[Andrew Kohlsmith]

> Combine that with dropping an FXO interface into a pstn environment
> where the transmission levels to the CO are basically unknown, SOHO
> impedence mismatches abound, bridged analog phone sets are commonplace,
> and assumptions that plug-n-play applies across the board including the
> x100p, its fairly obvious why so many people bad-mouth the "hardware".

I am badmouthing the hardware because I can drop an Adit600 FXO port on to the 
exact same line and have an order of magnitude better chance of getting 
adequate voice quality out of it.  I am waiting for my FXO module to arrive 
so I can see if I have similar experiences with it.

The X100P is a cheap hybrid interface.  I am not arguing that point.  I also 
believe, however, that using the X100P and reselling that particular brand of 
WinModem is giving a *lot* of asterisk newcomers a very bad taste in their 
mouths.  It is my sincere hope that the TDM400P's FXO module is a 
significantly better hybrid and that the Dev Kit is simply a TDM400P with FXS 
and FXO modules.

There's always a tradeoff between cost and performance.  It is my opinion that 
the X100P was a bad choice.

> Its also interesting that in about eight months on this list no one has
> asked what the milliwatt generator is for, how to find the telephone
> number of the pstn generator, how to measure the levels or what the
> objectives should be, etc.

I am pretty sure that most people wouldn't have the means to measure and apply 
that knowlege.  I know what a milliwatt generator is used for and I have the 
means to measure and adjust the hybrid to get the desired result, but I 
didn't have the knowledge that yourself and Mr. Adamson have just brought to 
the list.  In other words, I didn't know _where_ I needed to adjust the 
values to.  It's especially interesting how the hybrid should NOT be adjusted 
to get 0dBm on the 4-wire side to eliminate echo.  I would not have guessed 
that.  I was also lucky enough not to need to live with the X100P for very 
long.

> Maybe a couple of us should write a whitepaper for beginners on the topic.

I think that would be an incredible nugget of knowledge for the Asterisk 
community.  I know that I've got yours and Mr. Ferrell's messages stored away 
in my knowledgebase.  :-)

Regards,
Andrew