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[aprssig] Is there a place for APRS on 6 Meters?

Wes Johnston, AI4PX wes at ai4px.com
Tue Jul 28 21:56:39 UTC 2009

Lets also not forget that 9k6 is legal on 50mhz.  I had this same thought a
week or two ago... the closest low band tv station to us in SC is in Augusta
GA, but it's way up on 82mhz.  YAY!

Hitler gave great speeches too!

On Tue, Jul 28, 2009 at 17:14, Stephen H. Smith <wa8lmf2 at aol.com> wrote:

> --- A Six Meter Revival Is At Hand ----
> --- Is There A Place For APRS In It? ---
> With the shutdown of analog TV on June 12th, TV channel 2 RF has
> disappeared just about everywhere.   (ALL the TV stations indentifying
> themselves as "Channel 2" on digital in the major cities have "QSY"ed to UHF
> for their digital alter-ego.)  There are only 7 stations left physically on
> channel 2 in the entire country now!  All in smaller towns.  Here are the
> details copied from
>    <http://rabbitears.info>
> Actual
> Digital        RF        Display
> Channel    Channel    Callsign-City-State
> 2    3    KVBC-DT LAS VEGAS NV
> 2    2     WLBZ BANGOR ME
> 2    3     KOTA-TV RAPID CITY SD
> 2    2     KJWY JACKSON WY
> What this means is that, for the first time since the early 1950s, 6 meters
> is fully usable in nearly all areas of the US.  All the mutual interference
> issues to-and-from channel 2 TV are gone.    Even in these seven remaining
> areas, the steep-skirted emission mask for the digital signal should mean
> far less trash below 54 MHz. Not to mention that any "slop" from the digital
> signal will appear more like random white noise rather than discrete
> birdies, squeals and buzzes in ham receivers.
> The S9+ noise level of sync hash and video buzz from the lower sideband of
> half-megawatt ERP signals on channel 2 that rendered 6M unusable here in
> southern California (and many other urban areas) has disappeared.
> When KCBS 2 here in L.A. finally turned off their chan 2 analog
> "nightlight" station  on July 12th, the noise floor on 6 meters immediately
> dropped from S-9 plus to S-0 on my TS-690.   [ A "nightlight" was an analog
> station remaining on the air AFTER the JUNE 12th digital transition,
> broadcasting exclusively an endless loop of information on the digital
> transition and how to install a digital converter box.]
> I am predicting a renaissance  of activity on 6M, now that we can actually
> HEAR something.
> Is there a place for APRS here?   Should we (can we) stake out a national
> APRS channel on 6M?
> Obviously, all-in-one compact trackers will be hopelessly impractical on
> this band, due to the size of antennas and effective groundplanes.
> On the other hand, I AM interested in the possibilities for APRS from
> mobiles on 6M.  Low VHF has far superior long-haul propagation
> characteristics in open county with far less of the rapid fluttering and
> chopping that mangles data on VHF and UHF at greater distances.  [There is a
> reason that Highway Patrols and State Police still use 39 MHz for rural
> operations...]  With the proliferation of all-mode "DC-to-light" 100W mobile
> rigs like Icom 706s and Yaesu FT-857s (both of which have rear-panel
> mini-DIN "data" jacks), the potential for long-haul open-road APRS on 6M is
> there.
> Not to mention the occasional DX excitement when the band opens. [If this
> solar ultra-minimum EVER ends....]
> Years ago, before APRS, I did some packet data transmission experiments on
> 6 meters from a mobile running a Kenwood TM-742 with 50 watts out, here in
> Los Angeles.  I was absolutely astounded at how the 6M signal would
> propagate over and around hills, and through canyons and passes that stopped
> 2M dead in a mass of multipath phase distortion.   The only down side is
> that there is far more man-made electrical noise on 6M in built-up areas
> than on VHF.   [Low-band Motorola Micors had noise blankers, VHF and UHF
> didn't...]
> ------------------------------------------------------------------------
> --
> Stephen H. Smith    wa8lmf (at) aol.com
> EchoLink Node:      WA8LMF  or 14400    [Think bottom of the 2M band]
> Skype:        WA8LMF
> Home Page:          http://wa8lmf.net
> JavAPRS Filter Port 14580 Guide
>  http://wa8lmf.net/aprs/JAVaprsFilters.htm
> "APRS 101"  Explanation of APRS Path Selection & Digipeating
>  http://wa8lmf.net/DigiPaths
> Updated "Rev H" APRS            http://wa8lmf.net/aprs
> Symbols Set for UI-View,
> UIpoint and APRSplus:
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