water water everywhere
Wed Jul 16 21:13:05 EDT 2008
KNEW in Oakland has a two tower array at the edge of SF Bay right near
east end of the Bay Bridge. I've seen an areal photo and the towers
(they are self-supporting) actually stand in the (salt) water. I've
heard that, as the tide comes in and goes out, the electrical
characteristics of the towers change, which affects the tuning of the
array. The engineers rigged up some sort of clever but apparently
rather simple hydraulic/electromechanical arrangement to make the
tuning indifferent to the water level. Seems to me I heard that it
involves something like the float in a toilet tank probably linked to
a variable inductor or an air-variable capacitor or both. I wonder if
this arrangement grew in complexity a few years ago when the station
increased from 5 kW DA-N to 20 kW-D/5 kW-N DA-2. The day and night
patterns are similar (the day pattern appears to be a somewhat detuned
version of the night pattern), so maybe whatever worked for the night
pattern also works for the day pattern.
Dan Strassberg (firstname.lastname@example.org)
----- Original Message -----
From: "Paul B. Walker, Jr." <email@example.com>
To: "Keating Willcox" <firstname.lastname@example.org>
Sent: Wednesday, July 16, 2008 8:48 PM
Subject: Re: water water everywhere
> The station isn't on a boat, but 1220's tower in Providence is on a
> island in the middle of the river
> Paul Walker
> KNLV-FM Ord, NE
> On Wed, Jul 16, 2008 at 7:08 PM, Keating Willcox <email@example.com>
>> 1. Where was the station that had part of their signal on a boat,
>> in RI, so
>> the conductivity changed with the tide?
>> 2.We, WNSH, will be fine. We are about 30-40' above sea level mlw
>> we are only a half mile from Salem Sound.
>> 3. Forget global warming. Get your fur coats. CO2 has a minor role
>> to sunspots. I love the way National Geographic describes the
>> melting of
>> Greenland's glaciers as a catastrophic event. Hmmm.... the Vikings
>> herding sheep there less than 1,000 years ago until changes in
>> caused the mini-ice age.
>> First step: stilts! Gotta get the bottom of the base insulator well
>>> above high tide--like 100-year high tide. The work sounds
>>> Remember a few years back WBZ was going to replace its towers?
>>> went back almost to square one and reguyed them instead.
>>> guys were connected only at two points on each tower. Apparently
>>> towers flexed incredibly in high winds, which must be pretty
>>> common in
> Paul B. Walker, Jr.
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