[RTTY] signals over the pole

Don Hill AA5AU aa5au at bellsouth.net
Mon May 31 14:10:51 EDT 2004


Hello Jacques,

I've not experienced MMTTY not copying strong signals, regardless of whether
over the pole or multi-path.

I always use the profiles that come with MMTTY.  I have played around with
different settings but have not seen any significant differences to the default
profiles for standard, flutter or multi-path.

I've found the Standard profile works well for about 95% of RTTY signals.  From
here, UA9, UA0 and occasionally OH stations are fluttered and require switching
to one of the two flutter profiles.  Also, I occasionally use the multi-path
profile to copy KK5OQ, who is in the next state of Mississippi.  Otherwise, I
rarely need to use the multi-path profile.

I've also found that my HAL DXP-38 handles fluttered signals better than MMTTY.
I have an educated guess that expanding the passband helps fluttered signals.

I cannot explain why you would not be able to copy a strong signal with MMTTY.

73, Don AA5AU

-----Original Message-----
From: Jacques RAMBAUD [mailto:f6bki at wanadoo.fr] 
Sent: Monday, May 31, 2004 11:15 AM
To: Don Hill AA5AU; rtty at contesting.com
Subject: Re: [RTTY] signals over the pole 

Don and the group,
I take the oportunity of having RTTY experts on this reflector to bring again
the issue of decoding signals comming from the pole .Sometimes signals are 10 to
20dB above noise but no copy!!
Our experience is that MMTTY and TNCs (KAM /PKs) are quite close sometimes one
is better than the others but not by much.
We do not see much difference with MMTTY between the standard, flutered ,
multipath option , may be we have not found the right parameters , can somebody
help in this respect ??

I remember a friend mentioning a relatively old  US TNC maybe semi professional
maybe for military applications  that was quite good to copy this kind of signal
, any comments ?? any other strategy like antenna diversity  ?

Thank you all , 73
Jacques F6BKI







More information about the RTTY mailing list