I’m working from home today. I’m doing component level circuit prototyping and the workplace has no such facilities. So, with the O-scope lit up, a DVM, and a protoboard on the bench, I’m putting together a simple (small) triggered burst mode oscillator that will be triggered by a tiny GPS module’s pulse per second output. The end result is that when it is plugged into a telephone, one will hear a beep every second. The trick is that the beeps from multiple units in different locations will start at the same instant in time. Feed the beep into a phone, call a telephone number in a distant city, compare the beep start times between a local unit and what comes out of the phone and one can measure the transit time of a voice across a telephone system.
With the advent of digital telephones, the network is a minor part of the equation. Different phones take different amounts of times to do their job and different brands of phones working together can sometimes do unusual things. What I’m doing here will measure everything from the speaker’s mouth to the listener’s ear. Maybe that’s why it’s called mouth to ear delay. Hmmm.
I haven’t done much of this kind of work in probably 30 years. It’s nice to see the process hasn’t changed much and that many of the familiar components are still available–556 timers in particular. It’s nice to see that the old protoboard still works.
Once I decide my hair brained idea will work, I’ll put it onto something more substantial, hope nothing weird happens in the move, and build another one. If my experience holds true, the prototyping of such a simple thing will take an hour and getting it into a nice looking box will take the rest of the day. A packaging engineer, I am not.
On a sadder note. 31 years ago this week I descended into a hell from which I’ve only partially escaped.
I was at home, admiring my just purchased semester’s worth of graduate school engineering texts when the telephone rang. The caller identified herself as a nurse in the emergency department at the hospital where my fiancee worked. She plunged on, telling me my fiancee had collapsed and was being sent into surgery. Seemingly forever later I arrived at the hospital and after even more forever of a wait, the surgeon came out and used many scarey words. The worst ones were “cancer”, “advanced” and “very difficult road ahead”.
Four months later her nightmare ended. She was almost 22 and I was a very angry and lost 23 year old. After 31 years, I still wonder “what if”.
The reason I say partially escaped is that my wife of 25 years had many of the similar words used about her. Stage 3 breast cancer. After a year long flurry of treatments she now visits the oncologist every 3 months. So far, the news is good. I hope it stays that way.
My fiancee had been accepted to medical school and I’m absolutely certain she would have made it. My wife is an engineer.
Brains and beauty. Twice. Three times if you count our awesome daughter. I suppose I’ve been lucky.