🚀 go-pugleaf

In message <19960605.124615.46@xargle.demon.co.uk> Tony Howat wrote:

> In message <4p1r5o$huv@news.ox.ac.uk> Thomas Down wrote:
> 
> > Tony Pay (Tony@stsm.demon.co.uk) wrote:
> > : Can anyone help me with this?
> > 
> > : I can't get past login on Demon, using Termite or ANT Suite, while set
> > : faster than 38400.  I believe the II Dual card is supposed to let me do
> > : this even with my antiquated machine.  I have A420/1, 4Mb RAM, ARM3,
> > : RISCOS 3.1, USR Courier.  I'm using a PC style cable with the software
> > : configured appropriately. 
> > 
> > : Perhaps this is overly optimistic, but TCPIP is set at 115200 seemingly
> > : without problem.  Obviously I would benefit most from the higher speed
> > : while using the web browser - i.e. with the other two pieces of
> > : software.
> > 
> > Umm... Modems don't run faster than 28800 baud. This is supposedly more
> > or less the theoretical limit of what can be achieved over normal analog
> > 'phone lines. To go any faster, you'll need ISDN, or something similar.
> > Unless I'm missing the point completely...
> 
> I think he's talking serial speed which is really a case of the faster the
> better if your machine can cope with it, especially if you are using
> compression. Some modems do go faster than 28800 baud (34k ish), but not
> with demon.
>
I hope this helps. 

If it is properly configured the modem will connect at 28.8K
regardless of the DTE (serial port to modem) speed as this will 

be buffered.  Generally speaking the higher the DTE speed the 
better with the optimum value being roughly  calculated as basic 
connection speed multiplied by the compression efficiency.  
This is rarely higher than 28.8*2 so a DTE speed of 57.6k will do.  
Most people will select the next highest value (115.2K) to dredge 
out the last bit of speed available when the compression routine 
comes across a particularly compressable file but this isn't 
really necessary.  In fact with the speed limitations enforced on 
us all by the internet rapidly clogging a DTE speed of 38.4K will 
usually surfice even for a 28.8K modem.

Incidentally,  the card described should work up to 115.2K
on pretty much any machine, although this does not mean that 
the modem will work at these speeds.  As an example I have come
across several USR 28.8 Courier's that would only connect at
a DTE of 57.6K without errors and I have seen many USR 14.4K
sportsters that would only work reliably at a 19.2K DTE.
Make sure you have the latest revision bios for the modem.

A simple test would be to download the !connect comms program
and set the DTE to 115.2k.  Connect to a BBs (preferably in the 
early hours of the morning) at 28.8k and download a selection 
of text and Arc'd files.  If the connection is fairly fast and 
no errors are encountered you can be reasonably sure that this 
DTE speed will be reliable. 

It is also worth noting that compared to Ka9q the Acornet/
slipdial combination seems to be a little fussy, this could
contribute to the problem.  

As I said, hope this helps.........B

-- 
Barry Swanborough