Question by electrical2601: Where are some good resources in building an FM radio from scratch?
I want to learn FM radio reciever theory well enough where I can build my own FM radio from scratch without using someone elses skematic. I know it will probably be hard but I know it’s possible if I can be guided to the right resources.

Best answer:

Answer by amansscientiae
Try to find a seasoned ham who can explain the basics of RF to you. This stuff is not so much hard as it is tricky. It is also 10000% easier if you have the right tools and measurement instruments. To build a radio if you have both a spectrum and impedance analyzer is a walk in the park and extremely instructive. You will learn in no time and be an aspiring RF pro by the time you are done. But the same task without that equipment is a nightmare. Personally (I happen to be a professional), I wouldn’t go near any RF circuits without the right lab equipment. But maybe that just shows my age and limited willingness to frustrate myself when I know better.

Good luck and have fun!

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“War is Stupid” sign and US Capitol building at United for Peace rally and march on Washington, DC


Image by jcolman
"War is Stupid" sign and US Capitol building at United for Peace rally and march on Washington, DC.

Incidentally, this is my personal favorite out of all the sign/poster pictures that I took during the march/rally. I shot this picture facing east from the steps of the National Art Gallery.

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please answer…

Best answer:

Answer by fred k
So it’s the tangent function, where r is the radius or adjacent side
Tan of angle = opposite/adjacent = height of building/r

Tan 40.4° = WM/r
and
Tan 62.4° = ESB/r

since only want the ratios, can ignore r (=1)

WM:ESB = (tan40.4°):(tan62.4°) or 1:2.25

Know better? Leave your own answer in the comments!

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Suggestion of Building a FM transmitter at home

Some time ago I was looking for a small FM transmitter to use around my house and I wasn’t able to find anything useful. I found a few do it yourself electronics kits, and several portable or battery operated devices.

 

You love to listen to music while you are at home doing things such as chores or odd jobs. All your favorite music is on your iPod or your computer. You don’t really want to wear headphones or earbuds but you can’t hear your music when you are out of the room.

 

An easier solution is for the music to travel wirelessly throughout your home. This can be done quite simply using an FM transmitter. An FM transmitter is a device that plugs into your audio or video player and the sound is broadcast through the transmitter as an FM radio signal which can then be picked up by a receiver such as a radio.

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Using an FM transmitter could easily solve your problem of having music in any room of your house. Unfortunately most FM transmitters on the market have a short range of around 9 m which using an average radio isn’t a strong enough signal to reach all the rooms in your house.

 

In order to solve this problem you really need to find an FM transmitter that can broadcast throughout your home. You want to look for a product that is marketed as a whole house FM transmitter, rather than a regular FM transmitter. You also want to make sure that your whole house FM transmitter is stereo. To get good quality music you also want to have stereo FM radios in your home.

 

The simple FM transmitter links your home-entertainment system to a portable radio that can be carried around the house and into the backyard (see the figure). Using this device, music playing on the CD changer in the living room can also be heard on a portable radio by the backyard barbeque.

 

A much better solution to this is to make the background music journey easily inside the house. This merely needs using an FM transmitter, a tool connected to your own movie or even audio player to permit the actual seem to be broadcast because an fm radio transmission that may be acquired utilizing a recipient, just like a radio.

Rascal Flatts give us a taste of their brand new album with “I Won’t Let Go.” www.wplj.com
Video Rating: 4 / 5

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Question by DJ Schuby: Why is the Washington Monument not lined up straight with the Capitol Building and the Lincoln Memorial?
If you look at a map you’ll see that the Washington Monument is off center. I have heard that this was done for some reason but the person who told me could not remember why this was done.

Best answer:

Answer by DON W
My understanding is that the ground at the exact intersection point wasn’t suitable, so the original builders shifted it over a bit.

What do you think? Answer below!

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92% of Waste Recycled Using Modular Building Techniques

One of the benefits of modular building is the capability to recycle over 90% of the waste produced on site. A recent example of this can be seen at Havering College.

The College’s Ardleigh Green Road Campus has plans to comprehensively redevelop the entire campus, but due to the current economic climate, redevelopment is not able to move forward as quickly as they would have liked.

A new temporary building, therefore, was proposed to replace G Block, which was in a poor condition and required replacing in order to function properly. The new building would provide accommodation for the Estates department, ancillary buildings and add a much needed Higher Education centre and training facilities in a central location.

The new temporary modular buildings were made to the College’s specifications, replacing the original structures with a more pleasing aesthetic that matched the surrounding buildings and improved the visual impact of the site. The new, 840 square metre building was built using Unitrex and has a natural stone finish, aluminium windows and a complicated pitched roof design.

The college recognised Terrapin as the right company for the project: “There are a number of off site construction techniques, the best one on the market is arguably the Terrapin range of buildings which is the chosen method of construction for the building in this application. Terrapin respond quickly to deliver all the style and quality of a permanent building.”

The new temporary building needed to be up and running by mid Sept 2010 in order to keep essential courses running and to avoid disruption to students and staff. Off site fabrication is the ideal solution to the short lead times often associated with educational buildings, allowing structures to be assembled in a short time during holidays and fitted out before occupation.

The modular building techniques used implement a number of environmental policies and procedures to prevent pollution and to minimise the harmful effect of their actions wherever possible. To achieve such a high percentage of recycled waste, the following aspects were effectively managed:

Sustainably sourced raw materials;
Reduction of the consumption of non-renewable sources;
Efficient use of materials and equipment in product and construction processes;
Waste and discharges to ensure that waste is minimised, recycled and re-used where possible, or disposed of in a responsible manner;
Maintenance of site, buildings and employee environmental training.

Due to this sustainable practice, 92.36% of waste produced in constructing the temporary building at Havering Campus was able to be recycled, meaning just 7.64% was sent to landfill.

100% of aggregates, hard core, metals and plasterboard produced during the build was able to be recovered or recycled, totaling 10.43 tons of waste that otherwise would have ended up in a landfill.

Other materials, such as timber, cardboard, paper, plastic and glass were also recycled to the best of abilities, ranging from 55% to 98.92% of waste material being recycled. The grand total of material able to be recycled came to 20.18 tonnes – over 90% of the entire waste produced during the build.

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The Washington Star Building


Image by dbking
The Washington Star, previously known as the Washington Star-News and the Washington Evening Star, was a daily afternoon newspaper published in Washington, D.C. between 1852 and 1981. For most of that time, it was the city’s newspaper of record, and the longtime home to columnist Mary McGrory and cartoonist Clifford K. Berryman.

On August 7, 1981, after 130 years, the Washington Star ceased publication and filed for bankruptcy. In the bankruptcy sale, the Washington Post purchased the land and buildings owned by the Star, including its printing presses.

Evening Star Building at 1101 Pennsylvania Avenue, NW in Washington, D.C. The building is a contributing property to the Pennsylvania Avenue Historic District.The Washington Star was founded on December 16, 1852 by Captain Joseph Borrows Tate. Originally headquartered in Washington’s "Newspaper Row" on Pennsylvania Avenue, Tate initially gave the paper the name The Daily Evening Star and it would be renamed several times before becoming Washington Star by the late 1970s. In 1853, Texas surveyor and newspaper entrepreneur William Douglas Wallach purchased the paper. As the sole owner of the paper for the next fourteen years, Wallach built the up the paper by capitalizing on reporting of the American Civil War, among other things. In 1867, the group of invenstors Crosby Stuart Noyes, Samuel H. Kauffmann, and George Adams acquired the paper by each of the investors putting up US,333.33. The paper would remain family-owned and operated for the next four generations.

In 1907, subsequent Pulitzer Prize winning cartoonist Clifford K. Berryman joined the Star. Five years prior, he had created the teddy bear. Berryman’s career continued at the Star until his death in 1949.

The next major change to the newspaper came in 1938 when the three owning families diversified their interests. On May 1, 1938, Noyes, Kauffmann, and Adams purchased the M. A. Leese Radio Corporation, and acquired Washington’s oldest radio station, WMAL, in the process. Renamed the Evening Star Broadcasting Company, the 1938 acquisition would figure later in the 1981 demise of the newspaper.

The Star’s influence and circulation peaked in the 1950′s; it constructed a new printing plant in Southeast Washington capable of printing millions of copies, but found itself unable to cope with changing times. The management was closed to new ideas: nearly all top editorial and business staff jobs were held by members of the owning families, including a Kauffmann general manager who had gained a reputation for anti-Semitism, driving away advertisers. Suburbanization and television were accelerating the decline of evening newspapers in favor of morning dailies. The Post meanwhile acquired its morning rival, the Times-Herald, in 1954 and steadily drew readers and advertisers away from the falling Star. By the 1960s, the Post was Washington’s leading newspaper.

In 1972, the Star purchased and absorbed one of DC’s few remaining competing newspapers, The Washington Daily News. For a short period of time after the merger, both "The Evening Star" and "The Washington Daily News" mastheads appeared on the front page. The paper soon was retitled "Washington Star News" and, finally, "The Washington Star" by the late 1970s.

In 1973, the Star was targeted for clandestine purchase by interests close to the South African Apartheid government in its propaganda war. The Star, whose editorial policy had always been conservative, was seen as favorable to South Africa at the time.

In early 1975, the owning families sold their interests in the paper to Joseph L. Allbritton, a Texas multimillionaire who was known as a corporate turnaround artist. Allbritton, who also owned Riggs Bank, then the most prestigious bank in the capital, planned to use profits from WMAL-AM-FM-TV to shore up the newspaper’s finances. The Federal Communications Commission stymied him with rules on media cross-ownership, however; WMAL-AM-FM was sold off in 1977, and the TV station was renamed WJLA-TV.

On October 1, 1975, press operators at the Post went on strike, severely damaging all printing presses before leaving the building. Allbritton would not assist Katharine Graham, the owner of the Post, in any way, refusing to print his rival’s papers on the Star’s presses since that likely would have caused the Star to be struck by the press operators as well. Allbritton also had major disagreements with editor Jim Bellows over editorial policy; Bellows left the Star for the Los Angeles Herald-Examiner. Unable to make the Star profitable, Allbritton explored other options, including a joint operating agreement with the Post.

On February 2, 1978, Time Inc. purchased the Star for US million. Their flagship magazine, Time, was archrival to Newsweek, which was published by the Washington Post Company, and the purchase seemed natural. Management issues continued to plague the publication, however. Editor-in-Chief Murray Gart, former chief of correspondents at Time, had no experience managing a newspaper and little experience even writing for one. An effort to draw readers with localized special "zonal" metro news sections did little to help circulation. The Star lacked the resources to produce the sort of ultra-local coverage zonal editions demanded and ended up running many of the same regional stories in all of its local sections. An economic downturn resulted in monthly losses of over US million dollars. On August 7, 1981, after 130 years, the Washington Star ceased publication. In the bankruptcy sale, the Post purchased the land and buildings owned by the Star, including its printing presses.

Many of the people who worked for the Star went to work for the newly formed Washington Times which began operations shortly after the Star went out of business.

Writers who worked at the Star in its last days included Nick Adde (Army Times), Michael Isikoff (Newsweek), Howard Kurtz (Washington Post), Fred Hiatt (Washington Post) Sheilah Kast (ABC News), Jane Mayer (The New Yorker), Chris Hanson (Columbia Journalism Review), Jeremiah O’Leary (Washington Times), Chuck Conconni (Washingtonian), Crispin Sartwell (Creators Syndicate), Maureen Dowd (New York Times), Michael DeMond Davis, Jules Witcover (Baltimore Sun), Jack Germond (Baltimore Sun), Judy Bachrach

Vince on the Mixx


Image by dreamsjung

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War Department Building at 21st and Virginia Avenue, N.W., Washington, D.C. (LOC)


Image by The Library of Congress
War Department Building at 21st and Virginia Avenue, N.W., Washington, D.C.

[ca. 1943]

1 transparency : color.

Notes:
Title from FSA or OWI agency caption.
Transfer from U.S. Office of War Information, 1944.

Subjects:
World War, 1939-1945
Government facilities
United States–District of Columbia–Washington (D.C.)

Format: Transparencies–Color

Rights Info: No known restrictions on publication.

Repository: Library of Congress, Prints and Photographs Division, Washington, D.C. 20540 USA, hdl.loc.gov/loc.pnp/pp.print

Part Of: Farm Security Administration – Office of War Information Collection 12002-68 (DLC) 93845501

General information about the FSA/OWI Color Photographs is available at hdl.loc.gov/loc.pnp/pp.fsac

Persistent URL: hdl.loc.gov/loc.pnp/fsac.1a35461

Call Number: LC-USW36-750

Wheat land, Walla Walla, Washington (LOC)


Image by The Library of Congress
Lee, Russell,, 1903-1986,, photographer.

Wheat land, Walla Walla, Washington

1941 July

1 slide : color.

Notes:
Title from FSA or OWI agency caption.
Transfer from U.S. Office of War Information, 1944.

Subjects:
Wheat
United States–Washington (State)–Walla Walla

Format: Slides–Color

Rights Info: No known restrictions on publication.

Repository: Library of Congress, Prints and Photographs Division, Washington, D.C. 20540 USA, hdl.loc.gov/loc.pnp/pp.print

Part Of: Farm Security Administration – Office of War Information Collection 11671-16 (DLC) 93845501

General information about the FSA/OWI Color Photographs is available at hdl.loc.gov/loc.pnp/pp.fsac

Persistent URL: hdl.loc.gov/loc.pnp/fsac.1a34224

Call Number: LC-USF35-221

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Tokyo Government Building


Image by bsit
A view from the courtyard of the Tokyo Government Building

Tokyo Metropolitan Government Building


Image by ivva
"Tokyo Metropolitan Government Building", Tokyo, ??, Japan, ??, ????, ?????, ??, Shinjuku

en.wikipedia.org/wiki/Tokyo_Metropolitan_Government_Building

en.wikipedia.org/wiki/Tokyo_Metropolitan_Government_Building

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Springfield – Senate Chamber, Illinois State Capitol Building


Image by myoldpostcards

Springfield – Senate Chamber, Illinois State Capitol Building


Image by myoldpostcards

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