a zyxel omni ta-128 problem

• Messages sorted by:[ date ][ thread ][ subject ][ author ]

I have a Zyxel TA-128 ISDN terminal adapter that provides my
connection to the internet on one B channel, and the other B channel
is available for dial-in and dial-out modem connections via a USR
Courrier 28.8 external analog modem using one of the the analog RJ11
jacks on the back to the TA-128.  

The Courrier always worked perfectly for me when it was on a real
analog POTS line, but now I have problems when a caller tries to
dial-in and connect to it.  At 9600 baud, it seems to work OK, but at
28.8, the connection is usually completely useless.  My personal
observation is that the D/A converter in the TA provides considerably
more volume thru a regular POTS telephone set than the real analog
POTS line does.  I am thinking that this could cause the Courrier to
either saturate its analog amplifier on the receive direction, or
that the Courrier is overdriving the A/D converter in the transmit
direction. 

I know that there are gain controls using S-register settings, but we
have recently moved, and I have not located my Courrier manual yet.
Has anybody seen this ki9nd of behaviour before?  Does anybody know
the commands to twiddle the transmit and receive gain on a USR
Courrier? 

Thanks!

-- 
--------  "And there came a writing to him from Elijah"  [2Ch 21:12]  --------
R. J. Brown III  rj@elilabs.com http://www.elilabs.com/~rj  voice 847 543-4060
Elijah Laboratories Inc. 457 Signal Lane, Grayslake IL 60030  fax 847 543-4061
-----  M o d e l i n g   t h e   M e t h o d s   o f   t h e   M i n d  ------