I am sweating a little over the 4 electronics labs I have to finish by Wednesday. My trial version of Multisim expired and I was forced to purchase a license from National Instruments. Fortunately they have a limited license for active students that cost just under $50 including HST. As soon I've completed my writing assignments, I'll be building and testing virtual circuits on my ThinkPad.
Saturday, December 11, 2010
The final week of semester 1
This weekend I'll be very busy working on writing assignments and electronics labs. I have 2 formal reports to finish, one (partially written) on MPEG technology and another (not yet started) about the practical applications of our mathematics course. Both are due Monday. Also due are the informal midterm progress report (mostly written) and the Evertz tour report (almost finished).
I am sweating a little over the 4 electronics labs I have to finish by Wednesday. My trial version of Multisim expired and I was forced to purchase a license from National Instruments. Fortunately they have a limited license for active students that cost just under $50 including HST. As soon I've completed my writing assignments, I'll be building and testing virtual circuits on my ThinkPad.
I am sweating a little over the 4 electronics labs I have to finish by Wednesday. My trial version of Multisim expired and I was forced to purchase a license from National Instruments. Fortunately they have a limited license for active students that cost just under $50 including HST. As soon I've completed my writing assignments, I'll be building and testing virtual circuits on my ThinkPad.
The difference 4 months makes
Last night I decided to revisit a problem involving the antenna of my Redsun RP2100 PLL shortwave radio.
Earlier this year I made a rather hasty attempt to tighten the mounting mechanism of its telescopic antenna. It had been loose for some time, so I decided to remove it completely and reassemble it. For some reason (unknown to me at the time) the mounting screw would not go all the way in to the thread of the mount. The result was an even looser antenna that would crackle the audio any time it moved. The antenna itself didn't seem to make contact with the tuner circuitry, and I was forced to use external long-wire antennas as an alternative. This was more than inconvenient, because I was not able to receive stations as clearly as before, and long-wire antennas can be messy.
After months of substandard performance from this radio, I decided last night to revisit the problem. I removed the screws that hold the radio's plastic chassis together for the first time since its purchase in 2007. Once inside I was able to see 3 circuit boards with many resistors, IC's, capacitors, switches and potentiometers. 4 months ago, my eyes would have glossed over most of these components, and I wouldn't have given much thought to what they are, why they are there, or what they do. After nearly completing my first semester of the Broadcast Engineering Technology program, I can now name these components with a basic understanding of their function and purpose.
After further inspection I noticed a white wire soldered to the radio's antenna circuit at one end, and a circular metal terminal connection at the other end, hanging loose near the antenna mount. The terminal connection had a hole that matched the size of the screw that held the antenna mount together. At last I had identified my problem! When disassembling the antenna mount last spring, I had not replaced the antenna terminal wire next to the telescopic antenna mount before tightening the screw that held it all together. This resulted in 2 problems: 1) a terminal wire that only sometimes made contact with the antenna giving me poor reception and noisy audio on contact, and 2) an antenna mount that was physically loose because one of its pieces was missing. I reassembled the antenna mount correctly and tightened the screw until it was snug. Voila! I had a perfectly functioning radio once again!
Last night's minor radio repair made me aware of what the 25 volunteer hours required by our Community Connections course had given me. All those hours spent disassembling equipment and salvaging parts under Tim Rorabeck and CJLX had made me comfortable with taking apart electronic equipment, identifying its parts, and diagnosing problems without damaging the equipment. It also made me realize how ham-fisted my earlier attempt to fix this radio had been prior to my experience with the Broadcast Engineering Technology program at Loyalist College. I am looking forward to the skills and knowledge I will acquire in the following 4 months and beyond.
Earlier this year I made a rather hasty attempt to tighten the mounting mechanism of its telescopic antenna. It had been loose for some time, so I decided to remove it completely and reassemble it. For some reason (unknown to me at the time) the mounting screw would not go all the way in to the thread of the mount. The result was an even looser antenna that would crackle the audio any time it moved. The antenna itself didn't seem to make contact with the tuner circuitry, and I was forced to use external long-wire antennas as an alternative. This was more than inconvenient, because I was not able to receive stations as clearly as before, and long-wire antennas can be messy.
After months of substandard performance from this radio, I decided last night to revisit the problem. I removed the screws that hold the radio's plastic chassis together for the first time since its purchase in 2007. Once inside I was able to see 3 circuit boards with many resistors, IC's, capacitors, switches and potentiometers. 4 months ago, my eyes would have glossed over most of these components, and I wouldn't have given much thought to what they are, why they are there, or what they do. After nearly completing my first semester of the Broadcast Engineering Technology program, I can now name these components with a basic understanding of their function and purpose.
After further inspection I noticed a white wire soldered to the radio's antenna circuit at one end, and a circular metal terminal connection at the other end, hanging loose near the antenna mount. The terminal connection had a hole that matched the size of the screw that held the antenna mount together. At last I had identified my problem! When disassembling the antenna mount last spring, I had not replaced the antenna terminal wire next to the telescopic antenna mount before tightening the screw that held it all together. This resulted in 2 problems: 1) a terminal wire that only sometimes made contact with the antenna giving me poor reception and noisy audio on contact, and 2) an antenna mount that was physically loose because one of its pieces was missing. I reassembled the antenna mount correctly and tightened the screw until it was snug. Voila! I had a perfectly functioning radio once again!
Last night's minor radio repair made me aware of what the 25 volunteer hours required by our Community Connections course had given me. All those hours spent disassembling equipment and salvaging parts under Tim Rorabeck and CJLX had made me comfortable with taking apart electronic equipment, identifying its parts, and diagnosing problems without damaging the equipment. It also made me realize how ham-fisted my earlier attempt to fix this radio had been prior to my experience with the Broadcast Engineering Technology program at Loyalist College. I am looking forward to the skills and knowledge I will acquire in the following 4 months and beyond.
Sunday, November 21, 2010
Field trip to Evertz in Burlington
On Thursday November 18th, our entire Broadcast Engineering program boarded an early morning bus and traveled three hours west to Burlington, ON. There we spent five hours at the manufacturing plant and corporate headquarters of Evertz Microsystems. Evertz designs and manufactures cutting edge professional broadcast equipment for television, radio and internet-based media organizations. I had first heard of Evertz two months ago during a product demonstration given at Loyalist College of their HD2014 Video PassPort 1RU Multi-Path Video Converter, Frame Synchronizer and Decoder.
Shortly after our arrival, we were treated to a tour of their manufacturing facility. I was impressed that Evertz is among the few Canadian companies that do not outsource their manufacturing and assembly to other companies in other countries. The entire facility is extremely clean and has anti-static floors. Employees are required to wear wrist straps and must keep one foot on the floor at all times to prevent static discharge that can destroy tiny electromagnetically sensitive parts often found in integrated circuits (IC's). The Raw Stock room has an elevator storage system that delivers vacuum-sealed packages containing the parts used in the beginning stages when filling a work order. Evertz keeps product order turn-around times very short. Orders received early morning can be ready to ship to the customer by midday. We were walked through the many stages of the manufacturing processes, soldering machines fed with IC's in ribbon rolls, their testing and research and development departments.
During the afternoon, there were product demonstrations, and discussions about compression technology and employment opportunities at Evertz. For me, the compression technology discussion was the highlight of the afternoon. While I was already aware of where MPEG-2 compression is deployed, and where it is slowly being replaced by MPEG-4, I had only a vague understanding of how it actually works. It was explained to us as best as someone with a PHD level understanding in this area can convey to this first year college student. JPEG-2000 compression was also discussed which I was previously unaware of. The distinction between distribution codec’s and those used in digital cinemas was explained.
The afternoon's discussions put into perspective how much I have yet to learn about broadcast technology before I will have the skills and knowledge needed by a company like Evertz. I am only two and a half months into this three-year college program and Thursday's tour gave me a taste of what one potential career path actually looks like.
Shortly after our arrival, we were treated to a tour of their manufacturing facility. I was impressed that Evertz is among the few Canadian companies that do not outsource their manufacturing and assembly to other companies in other countries. The entire facility is extremely clean and has anti-static floors. Employees are required to wear wrist straps and must keep one foot on the floor at all times to prevent static discharge that can destroy tiny electromagnetically sensitive parts often found in integrated circuits (IC's). The Raw Stock room has an elevator storage system that delivers vacuum-sealed packages containing the parts used in the beginning stages when filling a work order. Evertz keeps product order turn-around times very short. Orders received early morning can be ready to ship to the customer by midday. We were walked through the many stages of the manufacturing processes, soldering machines fed with IC's in ribbon rolls, their testing and research and development departments.
During the afternoon, there were product demonstrations, and discussions about compression technology and employment opportunities at Evertz. For me, the compression technology discussion was the highlight of the afternoon. While I was already aware of where MPEG-2 compression is deployed, and where it is slowly being replaced by MPEG-4, I had only a vague understanding of how it actually works. It was explained to us as best as someone with a PHD level understanding in this area can convey to this first year college student. JPEG-2000 compression was also discussed which I was previously unaware of. The distinction between distribution codec’s and those used in digital cinemas was explained.
The afternoon's discussions put into perspective how much I have yet to learn about broadcast technology before I will have the skills and knowledge needed by a company like Evertz. I am only two and a half months into this three-year college program and Thursday's tour gave me a taste of what one potential career path actually looks like.
Friday, November 12, 2010
Fresnel lenses and Fresnel zones
After posting the previous blog entry, I was reminded of a new term I encountered last week. I was sure I had encountered this term before. I just looked it up and discovered why.
It turns out I had been introduced to the term 'Fresnel' previously, but in an entirely different context. When I researched the term Fresnel lens, I was immediately reminded of the Amateur Radio course I took last winter. Fresnel zones refer to elliptical radiation patterns of radio signals and the need to keep geographic obstacles outside this zone. Avoiding obstacles in your signal's Fresnel zone minimizes the distorted out-of-phase signals that commonly occur in mountainous areas.
As I discovered, the name Fresnel refers to Augustin-Jean Fresnel, a French physicist who invented a way of constructing refractive lenses with much lighter materials than were previously used in the early 19th century lighthouses. His discoveries about the behavior of light are not directly related to radio signals, but diffraction of radiation patterns are somewhat similar, hence the term Fresnel zone.
It turns out I had been introduced to the term 'Fresnel' previously, but in an entirely different context. When I researched the term Fresnel lens, I was immediately reminded of the Amateur Radio course I took last winter. Fresnel zones refer to elliptical radiation patterns of radio signals and the need to keep geographic obstacles outside this zone. Avoiding obstacles in your signal's Fresnel zone minimizes the distorted out-of-phase signals that commonly occur in mountainous areas.
As I discovered, the name Fresnel refers to Augustin-Jean Fresnel, a French physicist who invented a way of constructing refractive lenses with much lighter materials than were previously used in the early 19th century lighthouses. His discoveries about the behavior of light are not directly related to radio signals, but diffraction of radiation patterns are somewhat similar, hence the term Fresnel zone.
Overhead projectors
Tim Rorabeck took some much deserved time off Thursday and Friday of this week - the two days I usually commit to volunteering toward completion of my first semester practicum. While no progress was made this week toward my twenty-five volunteer hours, I did make significant progress on Thursday and Friday last week.
On Thursday November 4th, Tim took me to the second floor television storage area and put me to work taking apart several overhead projectors and stripping them of their most valuable parts. Powerful incandescent bulbs, mirrors, glass lenses and plastic Fresnel lenses are among the spare parts most in demand for the repair of overhead projectors still in active service.
As was the case with previous disassembly work, the first overhead projector took me much longer to take apart than subsequent units. Learning how these units were put together is the key to taking them apart systematically. Most of the discarded overhead projectors are Bell & Howell machines. They look as though they were made between the mid 1970's and the early 80's.
Thursday morning I was only able to disassemble four of these units. On the afternoon of Friday November 5th there were three of us working - Nicholas Slade, Calvin Vansickle and myself. Together we were able to finish taking apart dozens of units. There are at least half a dozen left to disassemble. Tim seemed very pleased that we were able to clear so much storage space in the storage area in so short a time, and I am pleased to have passed the half way point of my volunteer time commitment. Fourteen hours volunteered, eleven more to reach the required twenty-five hours.
On Thursday November 4th, Tim took me to the second floor television storage area and put me to work taking apart several overhead projectors and stripping them of their most valuable parts. Powerful incandescent bulbs, mirrors, glass lenses and plastic Fresnel lenses are among the spare parts most in demand for the repair of overhead projectors still in active service.
As was the case with previous disassembly work, the first overhead projector took me much longer to take apart than subsequent units. Learning how these units were put together is the key to taking them apart systematically. Most of the discarded overhead projectors are Bell & Howell machines. They look as though they were made between the mid 1970's and the early 80's.
Thursday morning I was only able to disassemble four of these units. On the afternoon of Friday November 5th there were three of us working - Nicholas Slade, Calvin Vansickle and myself. Together we were able to finish taking apart dozens of units. There are at least half a dozen left to disassemble. Tim seemed very pleased that we were able to clear so much storage space in the storage area in so short a time, and I am pleased to have passed the half way point of my volunteer time commitment. Fourteen hours volunteered, eleven more to reach the required twenty-five hours.
Wednesday, November 3, 2010
New routine, better time management
I am now in my eighth week of fifteen, semester one of six. Reading week is over, the first semester is now half over, and I am finding it something of a struggle to keep up with course readings. Reading ahead is the key to getting the most out of a lecture, and I am behind in half of my classes.
Yesterday, I tried reading in the library after class and found that I absorbed complex course material much more quickly than I do at home. I have come to the conclusion that I need a distraction free environment if I am to continue doing well in this program.
In the spirit of the old adage, "early to bed and early to rise, makes a man healthy, wealthy, and wise", I plan to begin each weekday, regardless of when my first class starts, at 6:00 AM. If I'm ready to leave the house by 7:00 AM, I can be on campus before 8:00 AM when the library and SAL lab open for the day with at least ten minutes to spare. Most days, that will allow me two or three hours for reading before class. I'm also planning to stay on campus until 6:00 PM every evening except Fridays. On Thursdays, my first class starts at 12:00 noon, and I plan to spend at least three and half hours doing work with Tim at CJLX toward my community connection volunteer hours. Since Friday's classes end at 12 noon, I will ask Tim if I could work a few hours in the afternoon as well.
If I can commit to this routine, I should be able to maintain grades in the upper 80's to 90's. This will be a great time to develop better habits, because I know there are more challenging times ahead.
Yesterday, I tried reading in the library after class and found that I absorbed complex course material much more quickly than I do at home. I have come to the conclusion that I need a distraction free environment if I am to continue doing well in this program.
In the spirit of the old adage, "early to bed and early to rise, makes a man healthy, wealthy, and wise", I plan to begin each weekday, regardless of when my first class starts, at 6:00 AM. If I'm ready to leave the house by 7:00 AM, I can be on campus before 8:00 AM when the library and SAL lab open for the day with at least ten minutes to spare. Most days, that will allow me two or three hours for reading before class. I'm also planning to stay on campus until 6:00 PM every evening except Fridays. On Thursdays, my first class starts at 12:00 noon, and I plan to spend at least three and half hours doing work with Tim at CJLX toward my community connection volunteer hours. Since Friday's classes end at 12 noon, I will ask Tim if I could work a few hours in the afternoon as well.
If I can commit to this routine, I should be able to maintain grades in the upper 80's to 90's. This will be a great time to develop better habits, because I know there are more challenging times ahead.
Tuesday, November 2, 2010
Disassembling a Dell Server from 2000
On Thursday October 28th, I spent the entire day in a CJLX production studio taking apart obsolete broadcast equipment and salvaging their still useful parts.
In the morning, I finished disassembling a switching circuit from a reel-to-reel tape deck I had worked with weeks earlier. Several toggle switches and button switches were salvaged from the circuit. Tim says they will be very much in demand by maintenance and other faculty members. Next, I took apart an archaic audio amplifier from which I salvaged some potentiometers, capacitors, and fuses.
I spent the entire afternoon taking apart an obsolete but still functioning ten year old Dell server that was decommissioned in 2006. Among the most interesting parts I found were three high wattage power supplies that were designed to fail over to one of two backup power supplies should the active supply fail. The large motherboard contained at least 6 RAM slots containing 128 MB and 256 MB RAM sticks that added up to 1.25 GB of RAM. By today's standards, this would not amount to much RAM, but in 2000 it was an incredibly large amount. The processor was an Intel Pentium III which again would be very slow by today's standards, but in 2000 would have ranked among the fastest processors available. There were three or four 160 GB hard drives in a RAID array designed to temporarily absorb a single drive failure with a low probability of data loss. I can see why this server was decommissioned in 2006 as the storage space and processing resources in it would at best barely meet CJLX' current needs without any room for data expansion or failure of any kind. That said there are components within the system unit that today are still quite functional that can be put to other uses.
By the time I had finished disassembling the server, I had completed an additional seven hours toward my twenty-five volunteer hour commitment. This brings my total practicum hours to eight and half, with sixteen and a half hours remaining. With the semester more than half over, I need to make sure I complete at least four hours each week this month.
In the morning, I finished disassembling a switching circuit from a reel-to-reel tape deck I had worked with weeks earlier. Several toggle switches and button switches were salvaged from the circuit. Tim says they will be very much in demand by maintenance and other faculty members. Next, I took apart an archaic audio amplifier from which I salvaged some potentiometers, capacitors, and fuses.
I spent the entire afternoon taking apart an obsolete but still functioning ten year old Dell server that was decommissioned in 2006. Among the most interesting parts I found were three high wattage power supplies that were designed to fail over to one of two backup power supplies should the active supply fail. The large motherboard contained at least 6 RAM slots containing 128 MB and 256 MB RAM sticks that added up to 1.25 GB of RAM. By today's standards, this would not amount to much RAM, but in 2000 it was an incredibly large amount. The processor was an Intel Pentium III which again would be very slow by today's standards, but in 2000 would have ranked among the fastest processors available. There were three or four 160 GB hard drives in a RAID array designed to temporarily absorb a single drive failure with a low probability of data loss. I can see why this server was decommissioned in 2006 as the storage space and processing resources in it would at best barely meet CJLX' current needs without any room for data expansion or failure of any kind. That said there are components within the system unit that today are still quite functional that can be put to other uses.
By the time I had finished disassembling the server, I had completed an additional seven hours toward my twenty-five volunteer hour commitment. This brings my total practicum hours to eight and half, with sixteen and a half hours remaining. With the semester more than half over, I need to make sure I complete at least four hours each week this month.
Wednesday, October 13, 2010
Getting my hands dirty
This morning I started work toward my Community Connection practicum. Tim took me to a small production studio at the far end of CJLX' studio complex where he had me dismantle a quarter inch reel-to-reel tape deck and salvage its useful parts. Apparently switches, terminal mounts, electro-magnets and even springs are among the items commonly sought by media school and maintenance people at the college.
Of the parts I found most interesting: three high capacity resistors connected in parallel, wired to one of the tape deck's mechanical circuits. In our Electronics Fundamentals and Digital Fundamentals classes we have been told that the physical size of the resistor is an indicator of its power handling capacity. In our labs we work with low capacity carbon resistors. It was nice to see the much larger high capacity resistors up close for the first time.
I hadn't taken apart consumer electronics in many years. This was my first time dismantling a piece of professional electronics and I thoroughly enjoyed it! It felt good to get my hands dirty, learning how all the parts work together. By the time I had to clean up for my first morning class I had the reel-to-reel machine almost completely dismantled and its salvaged parts sorted. Another 30 minutes of work and I should have it finished.
I left for my first class with a sense of accomplishment this morning. One and half hours completed, twenty-three and a half hours remaining and my Community Connection volunteer work will be complete. The ball is finally rolling.
Of the parts I found most interesting: three high capacity resistors connected in parallel, wired to one of the tape deck's mechanical circuits. In our Electronics Fundamentals and Digital Fundamentals classes we have been told that the physical size of the resistor is an indicator of its power handling capacity. In our labs we work with low capacity carbon resistors. It was nice to see the much larger high capacity resistors up close for the first time.
I hadn't taken apart consumer electronics in many years. This was my first time dismantling a piece of professional electronics and I thoroughly enjoyed it! It felt good to get my hands dirty, learning how all the parts work together. By the time I had to clean up for my first morning class I had the reel-to-reel machine almost completely dismantled and its salvaged parts sorted. Another 30 minutes of work and I should have it finished.
I left for my first class with a sense of accomplishment this morning. One and half hours completed, twenty-three and a half hours remaining and my Community Connection volunteer work will be complete. The ball is finally rolling.
Sunday, October 3, 2010
CJLX: My community connection placement
After two unanswered attempts to make contact with someone at TV Cogeco, I decided last week to proceed with plan B: CJLX. As luck would have it, CJLX's chief engineer and Audio/Video professor Tim Rorabeck teaches a second year class Wednesdays in room 3L10 prior to our Electronics class in the same room. I was able to ask him if he needed any technical assistance that I could use toward my practicum. Tim indicated that he had work for at least two of us, and agreed to meet Nick Slade and I Thursday morning to show us what he needed to be done.
When we arrived, Tim took us downstairs to what is commonly referred to in the industry as 'the boneyard', a storage space with a lots of old discarded audio/video equipment from the broadcast, journalism and other departments at Loyalist College. He showed us old overhead projectors, reel-to-reel tape decks, Sony CRT monitors, VTR's and countless other pieces of professional analog media equipment. Many of these items are still functional, but outmoded for today's digital media workplace. Tim wants us to disassemble some of these items and salvage any useful or valuable parts from them such as lenses and power cords from overhead projectors and connectors from the back of broken VTR's. Other items like still functioning Sony Colour CRT monitors and VTR's need to be tested and documented for any technical faults to be repaired before they're offered for sale.
While the above mentioned placement work isn't glamorous, I know that salvaging is widely used throughout the broadcast industry as a way to cut costs and waste in what is an already very capital intensive business. I was aware of similar practices during my previous volunteer experiences at not-for-profit community radio stations, and from listening to stories from broadcast engineers on the 'This Week in Radio Tech' podcast. Power cords and connectors individually aren't very expensive, but when hundreds are used each costing $5 or $10 salvaging does makes sense (as a basic example). An old CRT monitor or VTR that no longer suits a modern television studio might still suit a sister studio in a smaller market. Discarding a functioning piece of professional audio or visual equipment when it might be of use elsewhere is both wasteful and irresponsible to the environment.
I'm relieved to have found a fall placement for my practicum, and looking forward to taking apart some old gear that I may hear about but rarely encounter in my new career.
When we arrived, Tim took us downstairs to what is commonly referred to in the industry as 'the boneyard', a storage space with a lots of old discarded audio/video equipment from the broadcast, journalism and other departments at Loyalist College. He showed us old overhead projectors, reel-to-reel tape decks, Sony CRT monitors, VTR's and countless other pieces of professional analog media equipment. Many of these items are still functional, but outmoded for today's digital media workplace. Tim wants us to disassemble some of these items and salvage any useful or valuable parts from them such as lenses and power cords from overhead projectors and connectors from the back of broken VTR's. Other items like still functioning Sony Colour CRT monitors and VTR's need to be tested and documented for any technical faults to be repaired before they're offered for sale.
While the above mentioned placement work isn't glamorous, I know that salvaging is widely used throughout the broadcast industry as a way to cut costs and waste in what is an already very capital intensive business. I was aware of similar practices during my previous volunteer experiences at not-for-profit community radio stations, and from listening to stories from broadcast engineers on the 'This Week in Radio Tech' podcast. Power cords and connectors individually aren't very expensive, but when hundreds are used each costing $5 or $10 salvaging does makes sense (as a basic example). An old CRT monitor or VTR that no longer suits a modern television studio might still suit a sister studio in a smaller market. Discarding a functioning piece of professional audio or visual equipment when it might be of use elsewhere is both wasteful and irresponsible to the environment.
I'm relieved to have found a fall placement for my practicum, and looking forward to taking apart some old gear that I may hear about but rarely encounter in my new career.
Monday, September 20, 2010
Evertz presentation
Several of us first year Broadcast Engineering students arrived 30 minutes late to our COMM 1002 class this morning. We were invited to a 10:00 am presentation of new audio/video processors purchased by Loyalist College from Evertz Microsystems. While much of the subject matter discussed in this presentation was far beyond this year student's comprehension, I found it to be a worthwhile opportunity to see some of the gear used in the field, learn some new industry acronyms for further research, and meet several second and third year Broadcast Engineering students.
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