corrupt faxes

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Hi,

Henning R. Eggers wrote:
> Gert Doering wrote:
> > Well, up to maybe 10 lines or so are "perfectly ok". Some modems
> > have problems with top-of-page synchronization, and thus the first
> > few lines can indeed be corrupt.
> > 
> > How many messages do you call "many"?
> Never counted, but several sreen-fulls of them. It looks like
> every line is affected.

Have you tried "g3topbm -r"? (I would be surprised if that helps, but
one never knows how much "interesting" things keep to happen every day).

> > Might depend on the maximum speed - 9600 and 14400 usually use
> > different carrier types, and different timing, so that might make
> > a difference.
> I think I limited it to 9600 since the modem is on a DECT port of
> our PBX (Hagenuk Europhone XL). But mgetty recognizes a correct
> fax reception, gives the partner's station id and spools a fax
> file. Would that tell me that the carrier handshake went o.k.?

Yes. In class 2[.0], the modem is very sensitive to all the little
details, so usually, if no +FHS:nn message is seen, *everything*
went through fine.

On the other hand, I could imagine problems caused by the DECT part
(handshake is done with a 300 baud carrier, which is easy to send
even on wireless links, but page carrier *may* be more difficult - I
have no experience here).

Could you try running the modem on a "real" A/B port?

> > The Courier usually yields quite satisfactory results. Please make sure
> > that you use the very latest firmware version -- earlier models have had
> > bad bugs in the fax part.
> Not the latest but not really old. I never wanted or needed X2 so
> I never bothered upgrading:

Try getting the X2 firmware -- the fax part has been *very much* improved.

> Supervisor rev  049-6.2.2
> DSP rev   1.2.2

This is the second-to-last non-X.2 firmware, if I remember correctly
(the last was 6.5.3).

I think I had some real fax problems with that firmware as well, but the
X.2 firmware works very good (I have a customer that uses Courier modems
to send about 500 faxes/day - works quite well. It should be noted, though,
that we have a failure rate of about 5% [failed handshake or page transfer,
most of those are caused by "incompatible" machiens on the other side *or*
it works fine on the second try]

gert

-- 
Gert Doering
Mobile communications ... right now writing from *AWAY* :-)) 
... mobile phone: +49 177 2160221 ... or mail me: gert@greenie.muc.de
.