On Mar 29, 8:20�am, Steve Bonine wrote:
The recent discussions got me to thinking about how the current bands
are partitioned. �Taking a quick look at the current US allocation
s
indicates these portions of the HF bands in which phone is not allowed:

160: �None
80: � 3500-3600 � 20%
40: � 7000-7125 � 41%
30: � None
20: � 14100-14150 42%

Typo Alert: should be 14000-14150

17: � 18068-18110 42%
15: � 21000-21200 44%
12: � 24890-24940 40%
10: � 28000-28300 18%

The conclusion is that, with some exceptions, an individual who is only
interested in running SSB is excluded from around 40% of
most of the US allocations. �

40%? Let's do the math...

Setting aside the five channels called 60 meters, an Extra Class ham
in Region 2 has 3750 kHz of spectrum available in 9 bands:

160: 1800-2000
80/75: 3500-4000
40: 7000-7300
30: 10100-10150
20: 14000-14350
17: 18068-18168
15: 21000-21450
12: 24890-24990
10: 28000-29700

Of that 3750 kHz, 2743 kHz is available for voice modes, most
typically SSB and AM. That's 73.1% of the available HF/MF amateur
spectrum available for voice modes, and only 26.9% unavailable.

26.9%, not 40%.

Of course 160, 80/75 and 10 meters skew the numbers slightly.

But there is another factor to consider: DX 'phone.

It is common for DX stations to work 'phone down below the US 'phone
bands, to avoid QRM from US hams, who greatly outnumber the DX. So
when a band is open, the top end of the non-phone segments are
frequently full of DX phone QSOs, and unusable by US CW/data
operators. Every time the US phone subbands have been widened, the
'phone DXers have moved lower too.

The end result of this is that, when the bands are open for DX, the
amount of band available to non-phone modes is effectively reduced
below that 26.9%

Is that reasonable? �Is this bandplan maximizing the use
of the resource?

Depends what you mean by "maximize". The digital/data folks are
squeezed into only 1217 kHz of the 3750, which is 32.45%.

One definition of "optimum allocation" is providing the
same usability for operators of every mode.

But is that a definition we hams should use without question? Should
the users of wide modes be rewarded by getting more and more of a
limited band?

Imagine if the price you paid for gas depended on the MPG of the car
you drove, with low MPG cars paying less and high MPG cars paying
more. Or suppose gasoline were rationed, and ration cards distributed
the same way. Would that make the best use of a limited fuel supply,
by rewarding those who use the most?

�In order to accomplish this, one needs to
know the number of people who wish to use each mode.
�It's not possible
to directly and accurately obtain this number,
but perhaps counting the
number of QSOs in progress might approximate it.

That depends on when a sample is taken, though. During a contest or
other operating activity that favors one mode, the results may be very
unrepresentative.

In the absence of any data, I'm not going to speculate about
whether 40%
is a reasonable number. �Have there been any attempts at
measuring
utilization in an objective way?

One way to consider is how the bands are used in a situation like
Field Day, where voice, data and Morse Code modes are all in use
simultaneously, and records of how many QSOs actually resulted
available. Of course the results are somewhat skewed by the fact that
12, 17 and 30 meters are not part of Field Day, that FD isn't just HF,
and the different skill levels needed to use various modes.

73 de Jim, N2EY

wrote:

Setting aside the five channels called 60 meters, an Extra Class ham
in Region 2 has 3750 kHz of spectrum available in 9 bands:

160: 1800-2000
80/75: 3500-4000
40: 7000-7300
30: 10100-10150
20: 14000-14350
17: 18068-18168
15: 21000-21450
12: 24890-24990
10: 28000-29700

Let's not forget that while 160m is not partitioned in the U.S., the
ARRL band plan for the band calls for no phone below 1843 KHz
Digital signals stay between 1800-1810 and the 1995-2000 portion is used
for experimental/beacon use.

Dave K8MN