It is easy to see the vital role electronics plays in modern Music.Visit any music shop and you will see many electronic musical instruments and accessories. Many parts of the music that you hear today are created electronically. Look around and you will find that computers are involved in creation, production, distribution, and consumption of music in a big way. Since Electronics and Music are my passions in life, I feel really happy about their interplay.
Thinking about it takes me back to the fond memories of college days and my first encounter with electronic music. Please bear with me if I sound nostalgic as I try to gather the cherished memories from the golden period.
It was 1979, I was in Ravindra Bhawan hostel at Roorkee, enjoying my time as a second year student of Electronics degree. Electronics was a very new subject at that time, most of us in the class liked it but knew very little about it. Like other classmates, I was also fascinated with tiny electronics devices and had started trying to build small circuits with a few components as hobby projects, though not very successful. This brought me in touch with my neighbor in hostel, Piyush Maheshwari, who had a similar interest, and started what turned out to be a very close friendship later. The most important hurdle in the way of doing electronics was to have a supplier of those tiny components. With some efforts, we located Jain's Electronics shop in the old city that used to keep almost everything we required. It was a little far from our hostel, however that did not deter a bunch of energetic students like us. For us, going there walking or on a bicycle was as much fun as working on the circuit afterwards. We integrated it smoothly into our evening Bread-Pakora, Chai and gossip routine.
At that time, we used to desperately look around for ideas to build something. A classmate Mukesh Kacker used to keep a collection of Popular Electronics magazines that had interesting circuit ideas. Due to this collection, Mukesh was as popular among friends as students who had colorful magazines with educational material of another kind. We hobbyists used to borrow his magazines in an attempt to find something interesting that can be built with our available resources. Many circuits were simply out of our reach as they used advanced parts that were not available to us at that time.
One such part seemed to be IC555, that was very commonly used in most of the circuits we found in the magazine. An Integrated Circuit (IC) was a new concept for us as we had not seen one so far. So, I asked a friend one day,"How much would an IC555 cost?". This friend was known as a guru for his wisdom about these things, so he replied,"I do not know, but we can do an estimate by the components used in it."
He pulled out the internal circuit diagram of IC555 from a magazine, and proceeded to do a cost estimate part by part. As the guru worked out that with 23 transistors, 15 resistors, and two diodes, it added up to around Rs 200 for the IC, my jaw dropped since this was a huge sum that students like me could not afford to spend on hobby. I dropped the idea of doing a IC555 based circuit immediately. The massive internal circuit anyway looked scary since we were used to circuits using a few transistors. We were apprehensive about how will we ever troubleshoot a
complicated circuit like this if it does not work. In comparison, four transistors were enough to make a push-pull audio amplifier, and a complete AM radio could be built with just seven transistors.
A few months later, another classmate, Yashpal took charge of the Electronics Hobby club and he got us involved in it as well. Here I got to meet IC555 for the first time and it gave me a big shock to see that what I imagined to be a huge device turned out to be a very small 8 pin package.
After I recovered from the initial shock and surprise, I realized that the integrated circuit is now within my reach, courtesy Yashpal and Hobbies Club, and I can also take it home. Soon after that, Piyush and I started exploring circuits built around this IC, and discovered that it was an hobbyist's delight, promising to give us many more interesting circuits to build.We picked up a tone generator circuit using IC555 as an Astable Multivibrator, that produced an audible tone with a very few components. We managed to hook up an experimental circuit on a strip board, attached a speaker to its output and turned on the power; We expected a sound from the speaker but there was none. (I realized later that if only electronics was so easy to do, people like me would have no job). With repeated trial and error and help from the experts, we finally managed to reach the point where it produced a pleasant sound in the speaker. It was nothing less than a eureka moment for us. This discovery was a source of a great fun and it got our creative juices flowing. Over time, we discovered many different ways to utilize our new found circuit - to create doorbells, horns, alarms, buzzers, beep generators... and much more.
One day, Piyush came up with this brain wave that if we change the timing resistor, we can change the frequency and hence the tone of the generated sound. Can this be used to build an Electric Organ if we have a different timing resistor for every musical note? This idea led to an experiment using a preset in place of the timing resistor. We adjusted the preset till we got the tone matching with different music notes - sa, re, ga, ma. We were really thrilled at this result. It was indeed possible to build a simple music organ by extending this principle.
This got us busy on the project to build a Electronic Organ with new enthusiasm and kept us occupied for next few weeks. Together, we sketched out the circuit diagram with provision for 15 notes. It was decided to have only sa-re-ga-ma-pa-dha-ni notes as all our tuning was by the ear and we were familiar with these main notes only. Though we knew how to generate a particular frequency from our circuit, we had no knowledge of the exact frequency of musical notes, hence we could not use fixed resistors that were much cheaper. We had no choice but to spend money on 15 expensive presets.
The increased part count also made it imperative to use a Printed Circuit Board (PCB) to hold the parts. Piyush was a master experienced in the process of PCB making that involved careful painting the fine track pattern on the PCB, and etching it in Ferric Chloride solution. Once we had the PCB in hand, I could not wait to solder the IC and the components on it.
Finally the day came when we turned it on, and went through the usual struggle to make it work by finding solder bridges, open tracks, bad parts, reversed power supply and other faults. Once the basic circuit worked fine, we carefully tuned the presets for all notes to sound reasonably accurate. After a week of effort, we were ready with the guts of our Electronic Organ. The two of us were elated to see our latest project taking shape. As we touched a wire on different presets, it produced different notes.
All set to go? There was just one minor problem. How to play on this keyboard. We needed an stylus that can be touched on a key to play a note. This resulted in a search for another jugaad. Eventually we found that a multimeter probe is a reasonably good option here. So, our poor multimeter was left with one probe as we cannibalized it to complete our pet project. With this, we could easily play any note on the organ, and also glide it across a sequence of notes to create a unique sound.
This Electronic Organ was a source of great fun to us and our friends. It was a great feeling that we have built something that can create music. We showcased it in the Electronics Club exhibition that year and attracted a lots of fans and appreciation at the event.
From an electronics engineer's point of view it was a very basic circuit but as our first project with an IC, it gave us great experience. Piyush and I went on building several more complex circuits in the following years; However I always fondly remember this one as it was our first successful attempt to mix electronics with music.
Disclaimers:
I do not claim absolute accuracy for this post since the events took place 35 years ago and I do not have a diary. My intent in this post is to capture whatever memories I can gather from that time.
I regret I do not have any photo of the Electronic Organ. The pictures used in this post are just to illustrate the point. These are not from the actual model that was built. We did not have access to color photography at the time :)