> John GM4SLV wrote: > I agree that the actual QRG should be the one reported - but > AFAICT we'll still need to do our own maths to put the required > RF frequency into the right area of baseband on the waterfall. > > BTW I find most Olivia sigs in Europe around 14106.5 or 14107.5 > (centre)...with 1k/32 that puts the bottom carrier @ 14106 or 14107. > John GM4SLV
Hi John, There are a few digital modes that it is much more common to use and report USB dial frequency, rather than centre frequency, such as: Olivia (various flavors) ALE (125bd 8FSK ATM and DTM/DBM ARQ) MIL-STD 188-110 and derivatives (RFSM2400, etc) CCIR 493 (100bd FSK) The above modes tend to be operated in "channelised" configuration, always USB Upper Sideband. Olivia uses an ad hoc voluntary channel method, because it can decode far below the signal/noise level which can easily be tuned manually by an operator. Also, this helps operators to switch back and forth through any of the Olivia flavors, keeping the lowest MFSK tone at about 516Hz... whether using bandwidths 125Hz, 250Hz, 500Hz, 1kHz, or 2kHz. See this image for the various flavors of Olivia: http://hflink.com/olivia/olivia_flavors.jpg And this website for more Olivia info: http://www.hflink.com/olivia/ ALE and Selcall uses a standardised channel listing based upon USB dial frequency, and 188-110 stuff is usually associated with the same ALE channels. 73---Bonnie BA7/KQ6XA .
