RF is RF and the FCC does not care how the frequency expansion is done,
whether by VFO shift or supressed carrier tone shift. I am shocked that
Bonnie does not understand that simple principle. For example, true FSK
is done by VFO shift, but FSK is also done on SSB by tone shift. The
result is identical, the only difference being that the transceiver does
not have to be linear with FSK shift, but it does with tone frequency
shift to prevent splatter. The problem with ROS is that the frequency
shift is by a method too similar to that used in VFO-shifting spread
spectrum (frequency hopping) transceivers, so to the observer, there is
no difference. It is the frequency hopping that makes ROS spread
spectrum, and unfortunately, that is against the FCC regulations. If it
were not, there could possibly be spread spectrum transceivers using
tone shifts much wider than an IF bandwidth, even using soundcards, just
like SDR's spectrum displays use. In that case, more than one voice
channel would be taken up for the benefit of the SS user, to the
detriment of adjacent stations, or even those farther away, if there
were no other limitations on bandwidth utilized.
73 - Skip KH6TY
W2XJ wrote:
Bonnie you have a Ham unfriendly addenda. Say what you like but at the
end of the day it is BS.
------------------------------------------------------------------------
*From: *expeditionradio <[email protected]
<[email protected]>>
*Reply-To: *<[email protected] <[email protected]>>
*Date: *Mon, 22 Feb 2010 01:09:14 -0000
*To: *<[email protected] <[email protected]>>
*Subject: *[digitalradio] FCC Technology Jail: ROS Dead on HF for USA Hams
Given the fact that ROS Modem has been advertised as Frequency Hopping
Spread Spectrum (FHSS), it may be quite difficult for USA amateur
radio operators to obtain a positive interpretation of rules by FCC to
allow use of ROS on HF without some type of experimental license or
waiver. Otherwise, hams will need an amendment of FCC rules to use it
in USA.
Sadly, this may lead to the early death of ROS among USA hams.
If ROS Modem had simply provided the technical specifications of the
emission, and not called it "Spread Spectrum", there would have been a
chance for it to be easily adopted by Ham Radio operators in USA.
But, the ROS modem designer is rightfully proud of the design, and he
lives in a country that is not bound by FCC rules, and probably had
little or no knowledge of how his advertising might prevent thousands
of hams from using it in USA.
But, as they say, "You cannot un-ring a bell, once it has been rung".
ROS signal can be viewed as a type of FSK, similar to various other
types of n-ary-FSK presently in widespread use by USA hams. The
specific algorithms for signal process and format could simply have
been documented without calling it Frequency Hopping Spread Spectrum
(FHSS). Since it is a narrowband signal (using the FCC and ITU
definitions of narrowband emission = less than 3kHz) within the width
of an SSB passband, it does not fit the traditional FHSS description
as a conventional wideband technique.
It probably would not have been viewed as FHSS under the spirit and
intention of the FCC rules. It doesn't hop the VFO frequency. It
simply FSKs according to a programmable algorithm, and it meets the
infamous 1kHz shift 300 baud rule.
http://www.arrl.org/FandES/field/regulations/news/part97/d-305.html#307f3
<http://www.arrl.org/FandES/field/regulations/news/part97/d-305.html#307f3>
This is a typical example of how outdated the present FCC rules are,
keeping USA hams in "TECHNOLOGY JAIL" while the rest of the world's
hams move forward with digital technology. It should come as no
surprise that most of the new ham radio digital modes are not being
developed in USA!
But, for a moment, let's put aside the issue of current FCC
"prohibition" against Spread Spectrum and/or Frequency Hopping Spread
Spectrum, and how it relates to ROS mode. Let's look at "bandwidth".
There is the other issue of "bandwidth" that some misguided USA hams
have brought up here and in other forums related to ROS. Some
superstitious hams seem to erroneously think that there is an
over-reaching "bandwidth limit" in the FCC rules for data/text modes
on HF that might indicate what part of the ham band to operate it or
not operate it.
FACT:
"There is currently no finite bandwidth limit on HF data/text emission
in USA ham bands, except for the sub-band and band edges."
FACT:
"FCC data/text HF rules are still mainly based on "content" of the
emission, not bandwidth."
New SDR radios have the potential to transmit and receive wider
bandwidths than the traditional 3kHz SSB passband. We will see a lot
more development in this area of technology in the future, and a lot
more gray areas of 20th century FCC rules that inhibit innovation and
progress for ham radio HF digital technology in the 21st century.
Several years ago, there was a proposal to FCC to provide regulation
by bandwidth rather than content. However, it failed to be adopted,
and ARRL's petition to limit bandwidth was withdrawn
http://www.arrl.org/news/stories/2007/04/27/101/?nc=1
<http://www.arrl.org/news/stories/2007/04/27/101/?nc=1>
Thus, USA hams will continue to be in Technology Jail without access
to many new modes in the foreseeable future :(
Best Wishes,
Bonnie Crystal KQ6XA
