[Wswss] 902-928MHz Band Plan Proposal by ARRL will restrictWeakSignal use

[Wayne Overbeck]

Yes, that was an excellent memo, Greg.  THANKS!
I forwarded it to the ARRL VHF-UHF Advisory 
Committee.

73, 
Wayne, N6NB


--- On Mon, 4/9/12, K6XN <k6xn at att.net> wrote:

> From: K6XN <k6xn at att.net>
> Subject: Re: [Wswss] 902-928MHz Band Plan Proposal by ARRL will restrictWeakSignal use
> To: "'KJ6KO'" <kj6ko at innercite.com>, Wswss at mailman.qth.net
> Date: Monday, April 9, 2012, 3:14 PM
> Greg, ARRL and others,
> 
> THANK YOU!!!!  Very helpful information and discussion.
> 73, Ted, K6XN
> 
> -----Original Message-----
> From: wswss-bounces at mailman.qth.net
> [mailto:wswss-bounces at mailman.qth.net]
> On Behalf Of KJ6KO
> Sent: Monday, April 09, 2012 9:14 AM
> To: Wswss at mailman.qth.net
> Subject: Re: [Wswss] 902-928MHz Band Plan Proposal by ARRL
> will
> restrictWeakSignal use
> 
> HI Mark,
> 
>    Being both a 902 SSB operator and a
> repeater operator, I am on both sides
> 
> of the fence here.  As a coordinator, you can make your
> own band plan 
> according to your area.  Out here, we are running 25
> MHz splits on 
> repeaters, but as you noted, there is very little clear
> spectrum.  In fact, 
> there is actually only about 200KHz of clean spectrum for
> weak signal or 
> repeater inputs!  Anyone that has tried to put up a
> repeater that has an 
> input of anything higher than 902.200 will find about a
> 15-20db reduction in
> 
> signal due to the "noise" from spread spectrum equipment in
> the area.  That 
> topped with the new higher powered  licensed LMS
> equipment that may soon be 
> deployed nationwide, and is currently under test in the SF
> Bay Area, has a 
> VERY adverse affect on any usage of the 900 spectrum from
> 904-927MHZ.
> 
> 
> 
> As far as the "One type of surplus equipment", well that's
> not true.  There 
> is only ONE mfgr of an "amateur" 900 radio and it is the
> Alinco HT and it 
> will work anywhere, but it is only an HT and does not have
> the power to get 
> over most of the Part-15 noise.  That being said, not
> every ham can afford 
> one and uses the commercial gear, which is very difficult to
> get to receive 
> in the middle of the band or to transmit in the middle of
> the band if you 
> are using 915 for inputs.  Motorla, Kenwood and Johnson
> radios are all used 
> on 900 and most will RX at 927 and TX at 902-903 with
> "minor" modifications.
> 
> ALL require extensive modifications to operate to RX or TX
> in the 915 
> portion of the band.  But, it can be done.
> 
> 
> 
> 900 Repeater users outnumber weak signal operaters out here
> by about 100 to 
> 1 !  Can't speak for the rest of the country.  I
> do know that a majority of 
> repeaters everywhere are running 25 MHz, not 12, but there
> are still a few. 
> In that respect, the ARRL's old bandplan is outdated!
> 
> Also noted that most of the listed 900 repeaters in NY are
> 25 MHz split, so 
> not so sure how bad that change will really be!
> 
> 
> 
> Also, since the FCC decided to put Amateur Radio BELOW
> Part-15 equipment 
> with regards to the new LMS equipment, we have nothing to
> stand on!  You 
> heard correct!  LMS licensees must prove their
> equipment does not cause 
> "unacceptable" interference to Part-15 equipment but are
> required to do 
> nothing  for Amateur users!  This is a "backwards"
> direction in rule making 
> as far as amateur radio is concerned!!  Amateur radio
> has always been 
> "primary" where Part-15 is concerned, and I had the FCC back
> me up on that! 
> You can argue that all manufactured amateur radios fall
> under Part-15 (it's 
> on the back of your rig!) but  that fight is for
> another day!
> 
> 
> 
>   Due to the lack of an "updated" national band plan,
> the frequency 
> coordinators for the LMS licensees out here (a HAM) looked
> at the SARA band 
> plan and decided there were no repeaters below 927.5 and
> designed their 
> equipment to operate there and wiped out most of the
> repeaters in the South 
> Bay area!  Not the repeaters, but the mobiles and base
> operators trying to 
> listen to repeater outputs!  With 20+ 30W transmitters
> in the area, we don't
> 
> have a chance!  We got their coordinator out here and
> explained the local 
> band plan and how much HAM's in other areas of the country
> would be affected
> 
> and they are trying to make a change to stay below 927.0,
> but we will have 
> to wait on that.  Regardless, they have licenses all
> over the country from 
> 904-927.750 and that stuff will make most of the band
> useless to anyone if 
> it is deployed making 12MHz splits useless!  WE are
> prepared to use the 
> bottom 200KHz for inputs and the top 200 KHz for outputs if
> it comes to 
> that, but with over 50 900 repeaters in NORCAL and well over
> 100 in the LA 
> area, it is a pretty grim picture!
> 
> 
> 
>   That being said, if you would like to keep 12MHz
> splits in your area, that
> 
> is the option you have as a coordinating body, but, out
> here, we peacefully 
> coexist with the weak signal operators and the repeater
> operators in the 
> same portion of the band.  I could never see the need
> for a full 1MHZ for 
> weak signal on the West Coast.  Maybe you have more 900
> operators that need 
> a full MHZ in your area, but for most of the country, I
> don't see the need.
> 
> 
> 
> I have also found that the Noise Blankers on most radios
> look at SS signals 
> as pulse noise and pretty much eliminate it!  Not all
> of it, but most of it!
> 
> Much better than FM radios.  It's the "baby monitors",
> cordless phones and 
> broad spectrum transmitters that really kill
> everything!  LMS is almost 1.5 
> MHz wide each transmitter!  It's basically a local GPS
> system.
> 
> 
> 
>  Out here, the 900 repeater band is FULL of refugees from
> 440 where the USAF
> 
> has basically kicked most of the repeaters off the
> band.  I have done 
> numerous tests and anything above 902.200 is extremely 
> noisy and not fit 
> for a repeater.  The only place the SSB users can
> operate in the metro areas
> 
> is 902.010!  That's it!  Too much "junk"
> elsewhere!
> 
> 
> 
>   I am totally in favor of the new ARRL plan, as if it
> was in place a few 
> years ago, we would not be having issues with the LMS people
> out here.  It 
> can also be "fine tuned" for local use in your area. 
> Remember, it is just a
> 
> "suggestion" not a rule.
> 
> 
> 
> 
> 
>   73 ...
> 
> Thanks and beware of the upcoming LMS licenses!!
> 
> Greg Stahlman  KJ6KO
> Trustee  NC9RS  Northern California 900 Repeater
> System
> 300+W @ 902.010 SSB
> 50W 903.3 Beacon CM88ws
> 
> 
> US275 The band 902-928 MHz is allocated on a secondary basis
> to the amateur 
> service subject to not
> 
> causing harmful interference to the operations of Federal
> stations 
> authorized in this band or to Location
> 
> and Monitoring Service (LMS) systems. Stations in the
> amateur service must 
> tolerate any interference
> 
> from the operations of industrial, scientific, and medical
> (ISM) devices, 
> LMS systems, and the operations
> 
> of Federal stations authorized in this band.
> 
> 
> 
> LMS Band Licenses...
> 
> Block A: 904.000-909.750 MHz and 927.750-928.000 MHz
> Block B: 919.750-921.750 MHz and 927.500-927.750 MHz
> Block C: 921.750-927.250 MHz and 927.250-927.500 MHz
> 
> Noticed they stayed away from the 910-919 area...that's
> because there dozens
> 
> of other licensed commercial users in that area around
> here!  Very 
> busy....Very bad for repeaters!
> 
> Part 90-353d....
> 
>  "....Additionally, EA multilateration LMS licenses will be
> conditioned upon
> 
> the licensee's ability to demonstrate through actual field
> tests that their 
> systems do not cause unacceptable levels of interference to
> 47 CFR part 15 
> devices."
> 
> http://www.law.cornell.edu/cfr/text/47/90.353
>