The Joy of Local

RCA ST 2I’ve mentioned here and there the clubs and local organizations I’m involved in (Wisconsin Antique Radio Club, represent). I also try to get to local DIY meet-ups and sip and spins wherever possible. Getting to know and network with experienced designers and builders was and is one of the best parts of the hobby for me. Having someone you personally know and who personally knows you (and your experience and capabilities) is an important resource as you get started in DIY. A lot of the knowledge, especially in our hobby, doesn’t live online and the perspective of an ‘old timer’ is far more insightful than a website (my own included). So get out there and make friends as a newbie.  Most of us in the hobby do it for the passion and fun of it and are happy to share thoughts and suggestions with others.

RCA ST 1

In addition to getting to know other DIYers, being involved in local clubs puts you in touch with local vendors. Online stores are a great way to find that specific part or tube without a hunt, but part of the fun of DIY is scrounging and working with what you find. Unless you are from a big city, there probably aren’t any “DIY tube amp builder association” meetings in your area, so look for HAM or radio clubs or meets, too. Chances are good that there is at least one local organization that you can join and start attending events. Many small vendors are willing to make quite a trip to offer their parts and tubes and meeting these local businesses is an adventure in itself.

The NOS matched RCA carbonized ST envelope tubes pictured above came from the swap meet I attended this past weekend.  The price would make you jealous.  Since joining  my local radio club, I’ve started buying almost all my tubes at the monthly meets. Dave at Electric Guru Parts House is my local go-to.  Join your local club and find your own!

 

 

 

 

I love kits, too

Especially when they are high quality kits.  Here are the contents of a TubeCAD Aikido kit that just arrived. John Broskie’s boards are top notch, the parts are bagged and labelled logically, and the included manual is excellent.  I’ll be building this kit up in a unique way (see TubeCAD’s article on the SRCFPP) and will post a build and my impressions in the coming weeks.

In the meantime, if you aren’t subscribed to and reading The TubeCAD Journal, you should be. Also consider contributing to John Broskie’s Patreon: for less than the cost of a Netflix subscription, you’ll support excellent vacuum tube DIY content and resources for everyone in the hobby.

Walking the line

When I got started with woodworking and amp building, cutting a straight line was the most intimidating part of just about any project. Not having the space or justification for a table saw, I tried more than one way of following a line with a jig saw and circular saw before I found something that works for me. Now I do not shy away from ripping boards to specific widths quickly and it only took some scrap and ingenuity.

What I found was a really simple circular saw jig made of a three or four inch wide 3/4″ board and some ten or twelve inch wide 1/8″ sheet. If you can find a board with a straight edge (preferably machined right from the lumber yard), you can cut a straight line. The jig is simply the 3/4″ board glued to the overly-wide thin sheet. You then zip your circular saw down the board with the shoe pressed against the straight edge to cut off the excess 1/8″ material. Viola. You now have a jig that will always cut just as straight as the board you used to build it.

saw jig

Here’s a picture of my jig (rebuilt this weekend because the old one was getting chewed up):

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My board is a bit wider because I also use this with my router for insetting panels.

To use the jig, I mark the piece that will be ripped or cross cut in two places and then connect the dots with the now arrow-straight edge of the 1/8″ jig base. Clamp it down and then let the circular saw ride against the thick portion of the jig. Because the saw’s shoe doesn’t change width, it will always faithfully cut along the edge of the 1/8″ material, provided you are making sure it is following snug against the thicker board. Straight cuts don’t get easier than this and I’d wager that this is at least as fast as setting up a table saw for every cut.

As far as measuring, I’ve always got a combination square near at hand (great for marking holes in top plates, too). This makes setting a repeatable distance from an edge quick and easy.

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If the thought of table saws and messy cuts prevents you from tackling your next amplifier or speaker project, hit the bargain bin at the lumber yard and whip up a simple jig.  This hobby doesn’t require expensive equipment if you get clever with the tools on hand.

New Project: La Luciérnaga (PSU)

This write-up will have two parts.  The first (the PSU) is posted and hopefully I’ll have the amp write-up done shortly.  This project is the most ambitious one I’ve written up for the site so please excuse the omission of some of the finer calculations and details.

Although the power supply is rather complicated, the amplifier will be pretty straightforward (pinky swear). The supply can be used with other amps and the amp can be used with other supplies, which is one of the reasons I decided to split it into two pages.

Click here to descend into the madness!