Radio Active...

I've been a radio geek since about 1965 and a licensed Ham radio operator (off and on) since 1971. I didn't really understand much of the technical side of things until about 1977 or so, so much of my activities up until then were limited to just trying to make 'contacts' with other hams on the air...  Remember, this was long before the personal computer, the internet or cell phones!

It really wasn't until about the last 15 years that things really started to 'take off' for me in regards to building equipment for use in my station. My latest creation is an antenna tuner that is loosely based on one published in the 1995 ARRL Handbook.  What I couldn't find locally or in my 'junk box', I purchased online. But the majority of the parts (right down to the rectangular knobs) are surplus, NOS (new old stock) or 'used'.   I was able to produce the meter faces using software available on the web.  The cabinet is Aluminum sheet stock that a local metal fab business cut and bent per my specifications.  This was a design process from start to finish and I'm really happy with the way it functions.  Unfortunately the paint job didn't turn out well at all, but that's another story...  This ATU will provide a 1.1:1 SWR on all bands with my 140 foot wire antenna from 160 thru 10 meters.  Measured (estimated) loss is nearly non-existent on 160 thru 40 and about 3% at 10 meters.  Good enough for what I use it for...

At one time I was intrigued with building 'recreations' out of old issues of QST magazines that featured construction articles.  One such article describes a 'regen' from the mid 1940's.  I incorporated a couple of 'upgrades' to make it a bit safer and also less obtrusive from an RF standpoint.  The original circuit consisted of a 6J7GT as a regenerative detector with a 6V6GT in a single ended amp configuration.  Band changes occurred by swapping out plug-in coils.  While I kept the plug in nature of the coils to change bands, I mounted toroid coils inside the tube bases rather than 'air' windings around them.  This coupled with changing the 6J7GT to a metal jacketed 6J7 and the addition of a 6J5 metal tube as a RF pre-amp, helped to reduce generation of RF from the receiver.  The safety enhancement consisted of using a cable that plugs into the remote power supply, rather than the exposed screw terminals originally used by the Author. This eliminated any exposed contacts reducing the potential for any 'shocking' experiences.  I was pleasantly surprised at just how well the whole affair worked.  Regeneration was smooth and easily adjusted.  Finding parts that allowed faithful reproduction outside of the changes mentioned above was somewhat of a challenge.  The original cabinet wasn't available, but a similar 'slope front' cabinet was obtained from Bud Industries by special order.  Some components also had to be substituted, but for the most part remained very similar.   The interesting similarity between the original and the one I built, is that in 1944 some component shortages (due to the War effort) presented builders of the day with similar challenges.  The Author of the article claimed that parts shortages wouldn't pose as big a problem with this receiver (perhaps due to use of more commonly available items?).  At any rate, it is a nice addition to my 'Vintage Homebrew' radio collection.