Author: bertjerred

The New Champ, a Hot Apple, a Tabula Rasa, a Hat Head, a Solder Bath, and a Patchwork Test Kit

Thanks, John & Family for bringing this, the “new champ,” to Yankee Swap. It’s shown next to its predecessor (left).

This Apple router works, but it gets hot. Time to take it apart and find out why. If I can’t fix it, I can at least say I’ve seen inside and will earn the benefit of more knowledge. Plus, who knows what little parts I might find?

Here’s the shell of a burnt-out PA mixer. Of course, I desoldered the 40ish variable resistors, along with 1/4″ audio jacks and XLR inputs. Now, I’m devising a replacement panel and a whole new functionality.

Quick side note: look at my hat head. Holy shit. What a weirdo.

Speaking of bathing… I’d really like to come up with a horribly toxic fire hazard solder bath for these boards. I shall not throw them away yet, because there is still logic (i.e., ICs) to be harvested. These, by the way, are pellet stove timers running on PIC microcontrollers. I think I could learn to program those!

And lastly, look how nice this transistor tester looks as a “kit” inside the back of a former salinity tester. Note: that’s my USB 9V battery on the left.

Reverb, Tremolo, and Knobs: Is it worth whatever disease I’ll probably get?

I recently acquired this amp head. When I got it home, I decided to not bring it indoors – and boy am I glad. When I opened it up, the mouse who had been living inside jumped out and ran away. Incidentally, I hear he…

New Song: Wings

Wings by Bert Jerred

Variable Band Pass Filter Idea, using Salvaged Air Dielectric Capacitors?

Testing capacitors today… Below I explain why.

I have procrastinated serious filter experiments for too long. Today, after a quick review of some basic concepts, I began to speculate about a variable filter module.

Defining the outer edges of a Band Pass filter makes enough sense – and leads me to the idea of a potentially chaotic (in a good way) variable array of components. What if I could, manually or otherwise, shift my upper and lower limits?

Plus, haven’t I been looking for an excuse for ages to use these salvaged variable capacitors? The answer is yes.

Thus, the time has come to get systematic about it. Today, I took measurements of the capacitance of several old pieces. It looks like I have everything I need to build an interesting audio filter experiment box.

Testify and One Word

Testify by Bert JerredOne Word by Bert Jerred

Thank You, George Lucas

Episode IV, “A New Hope,” introduced a fictional world to my 6-year-old mind that I’ve now enjoyed for decades. It is sad and exhausting to see so many armchair critics write and say so many negative things about a franchise that is meant to be…

Electronics: 2019 in Review

For a little over a year, I’ve been going pretty steadily at electronic devices: trying to understand them, create them, and deconstruct them. I now know so much more than when I started, though I have exponentially more yet to comprehend. Here’s a selective review of the things I’ve been doing. It’s fun to look back before continuing forward.

Around this time last year, I had just figured out how to make Schmitt Trigger-based square wave oscillators. I was also beginning to see raw materials in the form of discarded everyday objects. Repurposing other things quickly became almost as much fun as making interesting noises.
I was also trying to come up with keyboard mechanisms like this one (above), which contains a minimal voltage divider circuit.
This led, eventually, to my own take on a modular system.
By February, I felt confident enough to try sending out Gerber files for fabrication. This remains one of the absolutely most fun parts of designing electronic things. It makes a hobby-level project feel real.
While working on one after another project, I was blessed with a huge collection of vintage parts and components from my Dad. He also helped me get a Lowrey organ into my tiny little house. I’ve taken almost everything apart by now – to study the designs and to scrap for useful components.
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By August, I was refining everything I’d been learning and starting to make ever-increasingly sophisticated devices, like this (above), which became a self-contained multi-oscillator synthesizer with a 4-channel mixer and a few rudimentary built-in effect options.
As Fall approached, I was capturing samples and creating ambient audio, music, and this (pictured) soundfont.
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Candy 🌽 progress. #arduino

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Through November, I returned to the keyboard challenge… How best to control DIY noisemakers? This, alongside some preliminary “branding” ideas. Much of the work begun in the late Fall continues at the time of this writing.
My projects continue to evolve, though I am waiting until the holiday fun settles down before starting a new notebook and trying to settle on my next electronics focus.

Music: 2019 in Review

As I look back on the year with a focus on music-making, I’m proud of these accomplishments and very excited to be writing new songs. Here’s a quick summary of what I’ve been up to. Jamendo On Jamendo, I am proud to see that I…