[HamWAN PSDR] East Tiger Mountain cell site on the air

[Dean Gibson AE7Q]

Ah, OK the 240 degree (+-60) sector probably isn't going to work (I need 
something that covers 340 degrees).  Darn.  I may try the Haystack site, 
but that has some antenna siting difficulties.

On 2015-06-22 12:48, Bart Kus wrote:
> Hi Dean,
>
> I think it would help in discussing these comparisons if you were to 
> express the RF power not in terms of absolute power, but in terms of 
> power spectral density (W/Hz).  The 1W modem is set for 5MHz bandwidth 
> when communicating, so its PSD is 0.2uW/Hz.  Your 0.1W handheld is set 
> for 25kHz bandwidth, so its PSD is 4uW/Hz. That's 20x higher power 
> density.  If the noise floors of both spectrums were equal (which they 
> aren't) that would mean a 13dB increase in the ability of the FM radio 
> to discern a signal, compared to the modem.
>
> So 70cm FM has a lot going for it here.  It has better NLoS 
> propagation combined with a theoretical 13dB PSD boost.  On the flip 
> side, you have the 30dBi gain of the modem dish helping you to 
> compensate for those losses.
>
> This weekend I'll be running our first tests of the 900MHz gear in 
> NLoS conditions.  I did some lab tests on it over the weekend, and it 
> looks like @ 5MHz bandwidth it transmits just about 1W.  The signal, 
> being OFDM, isn't very tight, so we'll have to be very careful with 
> 900MHz repeater co-location.  We'll also have to watch out for 
> colocated 800MHz users.
>
> Regarding you linking to ETiger, there's a bunch of trees in the way, 
> but give it a try!  The mountain tower unfortunately does not clear 
> the surrounding tree line.  If someone feels like donating a 60ft 
> tower for up there, I'm sure that'd help.  :)  Also, keep in mind that 
> due to the tree issue, ETiger was only installed as a single sector 
> site.  Sector 3, aimed at 240 deg.  Have you tried aiming @ Haystack 
> yet?  Nigel just moved and is linked up to it now from Everett.  We 
> need to do some tree pruning @ that site to raise its signal levels.
>
> --Bart
>
>
> On 6/22/2015 11:04 AM, Dean Gibson AE7Q wrote:
>> Recently I noticed that I can access the WA7HJR (444.65MHz) repeater 
>> on East Tiger, from my home in Mill Creek, with the Icom and Yaesu 
>> handhelds at *0.1W*.  Reports are that it is a bit scratchy, but 
>> pumping the power all the way up to *0.5W* gives a reported clean signal.
>>
>> OK, that's 70cm, not 5cm.  However, I've long been able to access 
>> KB7CNN (1292.2MHz) at the same site with *1W*.
>>
>> All antennae above are omni.
>>
>> Meanwhile, my connection to the Paine site has dropped in the last 
>> month from -77dBm to -84dBm.  If last year is any indication, I have 
>> about 30 days until I lose the connection to Paine for another six 
>> months.  Originally I thought this was due to seasonal foliage 
>> growth, but since reception didn't come back until late February, I 
>> think it's something else.  Just to one side (a couple hundred feet) 
>> of my direct path to Paine, is a *huge* water tower just south of 
>> 132nd Street, and I'm wondering if that was serving as a reflector 
>> when it was full, and not so much as it emptied during the summer (or 
>> maybe partially resonant or energy absorbing?), and not refilled 
>> until the winter.  That hypothesis fits the timeline better than 
>> foliage ...
>>
>> Anyway, when I get the time this summer, I will try moving the 5shpn 
>> & antenna to the south side of my house and try to connect to the 
>> HamWAN site at East Tiger.  Using Google Earth, I see that the 
>> bearing from my house to East Tiger is 156 degrees.  I also see that 
>> the bearing to the Baldi site is 160 degrees, a *four degree* 
>> difference.  Google Earth's elevation plot shows a clear path to both 
>> East TIger and Baldi, the latter path *barely* clearing the terrain 
>> just west of East Tiger.  VE2DBE's Radio Mobile Online ( 
>> http://www.ve2dbe.com/rmonline.html ) plot agrees.
>>
>> This brings up the subject of common sector frequencies. 
>> Theoretically, the narrow beam of my antenna dish (isn't it about 3 
>> degrees?), coupled with East Tiger being only 28.3 miles away 
>> compared to Baldi at 47.8 miles, I would think would resolve any 
>> interference.
>>
>> Thoughts?
>>
>> On 2015-05-31 19:50, Bart Kus wrote:
>>> We put a new cell site on the air this weekend.  It's @ East Tiger 
>>> Mountain, and radiating @ 240 degrees (Sector 3) only. It's linked 
>>> directly to the Tukwila datacenter, and has a second link to 
>>> Snohomish DEM ("Paine"), but that's not yet configured for routing. 
>>> This site is 1500ft higher than our existing Mirrormont site, and 
>>> will serve to replace it.  It's superior location and superior 
>>> connectivity are a double-win. Mirrormont has been re-configured to 
>>> be on the Sector 2 frequency temporarily so as not to conflict, but 
>>> will go off the air at some point in the near future.  If you're in 
>>> the coverage area try to give it a go and report back!
>>>
>>> --Bart
>>
>>
>>
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