Shotwell had the Knack (Car Knack), and so does Jay Leno

I've joked about homebrew cars -- we have a bumper sticker on Café Press that says "My Other Car Was Homebrewed From Junkbox Parts."  Well, in this video Jay Leno shows us a true homebrew car, this one built by a 17 year-old in 1931.  In the video you will hear some interesting comments from Jay on the kind of technical and mechanical skills that were expected of young men in the 1920s and 30s.  At the end of the video, watch Jay suffer the consequences of replacing a 20 amp fuse with an 8 amp fuse.  Who among us have not done something similar?   

Cool, Blue, and Homebrew! Pete Juliano's Tiny SSB Rig

Blue is the new Black!  I think some smart paint manufacturer should put a trademark on "Juliano Blue."

Check out Pete's latest efforts:
http://n6qw.blogspot.com/2016/07/small-radio-big-signal.html

Building LC Oscillators

Yesterday I came across this very nice video -- I thought you guys would like it.  2E0VIR obviously has The Knack!

I'm building a very simple LC VFO today. This is for the HRO Dial Receiver that I've been slowly working on. Mine is a Hartley, from Chapter 3 Figure 7 of SSDRA.   Stay tuned!

CBLA Dallas Division: Multiple Mighty Mites in the Lonestar State

Bill:

Just thought you would like to know that I am a new member of the color
burst army.  I am also a member of the Dallas Makerspace and our Amateur
Radio Special Interest Group is planning on offering classes (open to
HAMS and non-HAMS) where we build these Mighty Mites for the colorburst
frequency.

The class version will have a resistive dummy load instead of antenna,
to allow the project to be built by non-HAMS.  The idea is to get our
HAMS who just use commercial radios interested in building radios.  It
is also to get our general members (who like making things) into HAM radio.

Walter

In Search of the Elusive Imperial Whitworth

This beautiful old variable capacitor came out of a 1930's British regen receiver that I picked up years ago at the Kempton Park rally near London.  When I rebuilt that receiver, I found that the cap was thoroughly stuck.  No amount of solvents could loosen it.  I put it in the junk box and used a more modern cap in its place.

When planning for my current BIG VFO project (see yesterday's post) I re-read Frank Harris's chapter on VFOs.  Frank recommended a non-linear cap -- actually a cap that maintains a constant percentage change in capacitance as it goes through its tuning range.  My old British cap seemed to fill the bill.  Also, it appears to be brass or bronze which is said to have better temperature stability.  So I pulled the Brit cap out of the junk box.  It was still stuck, but as I tugged on it a bit, it suddenly loosened up.  Wow!  TRGHS.

When I tried to mount the capacitor in the QF-1 box, I discovered another problem:  the nut for the main mounting screw was missing.   And guess what:  None of the nuts in my "big box of screws and nuts" (I know you guys all have one of these boxes) was the right size.  Or, as Pete put it, all were of two sizes: a bit too big, or a bit too small.

Dex ZL2DEX informed me that the needed nut was likely an "Imperial Whitworth" (Don't you love British names?).  I started to think about how to get such an elusive part.... I thought about walking into Home Depot and asking them where they keep their Imperial Whitworths.  This wouldn't have been productive.

Then I started to wonder where the original nut went.  It would have stood out in my junk box because it is brass-colored.  I looked again in the junkbox.  No luck.  Then I realized that I might have used it to mount that replacement cap in my rebuild of the old British regen.  I pulled that old beast (wooden chassis!) off the shelf.  There it was, the needed brass nut.  Cap and nut were reunited, problem solved.   

It is kind of fun to include an old part like this in the new project.

Thanks Dex.  And thanks again to Frank Harris for the great book.