BITX Build Update #18 -- BITX in a Box?

I've really been enjoying using my BITX17 without an enclosure.  Having all the electronics exposed on the workbench really accentuated the homebrew nature of this rig.  But obviously it was time to box this thing up.  At a local craft store, I found a wooden box that is exactly the right size for my BITX copper clad board.  I put the BITX in the box yesterday.  I kind of miss the exposed electronics.  

The far left control is AF gain.  The need for a few inches of wire to the pot has introduced a bit of AC hum.  I'll try to knock this down with better shielding on the lead to the pot.

But this gets brings us too a bigger question: the need for a cabinet that shields.  Obviously the wood shields it only from dust.  I know there are some benefits to putting this thing in a proper metal box.  The AC hum would be less of a problem.  Also -- listen to this -- in the morning, before 17 opens, I can hear -- faintly -- the WWV transmission on 5 MHz (recall that the IF in this rig is 5 MHz).  And if I ever build an external linear amp for this rig (I might), I guess a proper metal box would help prevent the kind of oscillation that often drives me crazy on these kinds of projects.

So, what do you guys think?   Stick with the wood, or put it in a metal box?   Any thoughts on putting metal shielding material around the inside of the box (thick aluminum of tin foil)?    

(The other black control knob is for a rotary switch that will allow me to select among two or three crystals for the VXO. )

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40% Off SolderSmoke Book!!! Through 4 November

And on all Lulu books.

Just use the coupon code FALLSALE40 at checkout.

http://www.lulu.com/spotlight/soldersmoke


Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Arecibo Birthday

Thanks to Bob Crane for this birthday alert:

The Arecibo Observatory opened on this date in 1963. At a diameter of a thousand feet, it's the largest single-aperture telescope ever built. It's also got the largest focusing dish in the world, which gathers electromagnetic waves from space. Located near the city of Arecibo in Puerto Rico, it's close to the equator, which enables it to "see" (via radio waves) all the planets in the solar system; within six months of its opening, it enabled scientists to study the rotation rate of Mercury and determine that it rotated every 59 days, rather than 88 as was previously thought. It's also been used for military purposes like locating Soviet radar installations by tracking their signals as they were reflected off the moon. It's provided the first full imaging of an asteroid and also led to the first discovery of planets outside our solar system.

In 1999, it began collecting data for the SETI Institute; SETI stands for "search for extraterrestrial intelligence," and the organization looks for deliberate radio or optical signals from other planets. The Arecibo Observatory also sends data over broadband to the home and office computers of 250,000 volunteers, who, through the Einstein@Home program, donate their computers to be used for data analysis during periods when they would otherwise be idle. A year ago, three such volunteers in Iowa and Germany discovered a previously unknown pulsar, 17,000 light years from Earth.

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Brooklyn Bike Generator -- Want one!

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

The New "Gold Standard" in QRSS Grabbers

Bill 

I just discovered Scott Harden's "QRSS Plus" grabber aggregator...

http://swharden.com/qrss/plus/

Check it out - it is the new "Gold Standard".

73, Paul

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

An Interesting Idea for Checking Crystal Filter Passbands

Today at 9:37 AM

Hi Bill,

Just listened to your last soldersmoke blog with reference to xtal filter checking using a DDS and scope. What do think of this idea to check filter performance?

http://www.qsl.net/7n3wvm/Fil_Meas.html

 Logical, relatively easy to build and NO digital electronics to deal with. 

Best 73

Rick G6AKG

PS keep up the great work, love the Blogs.

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20

Slide Show of BITX 17 Build

As I was building this rig, I periodically stopped and took a picture of the board.  I think the resulting slide show is kind of fun.  Check it out:  There is a button to launch the slide show.

http://www.flickr.com/photos/106886073@N04/sets/72157637045750216/

Our book: "SolderSmoke -- Global Adventures in Wireless Electronics" http://soldersmoke.com/book.htm Our coffee mugs, T-Shirts, bumper stickers: http://www.cafepress.com/SolderSmoke Our Book Store: http://astore.amazon.com/contracross-20