I am using the 120-117 transformer. I only changed the 47uF for a 10uF film cap and the 150uF for a 200uF film cap. Also I have a choke, will try a 12H instead of the 7H I was using before. I no longer use the motor run cap.
Gotta love the date stamp on that drawing. Tek made good stuff back in the day, they still do, but not up to the quality of what they did back then.
The tek stuff up until the 89’s or 90’s was built like cost-no-object military gear.
When they received equipment in their factory service department for repair. The first thing they would do is take the covers off and put it in a dishwasher! A tech that worked there told me about it.
I’m sure you can search for it with goog or whatever.
Also, search for Tektronix hifi or stereo equipment. They had a large HiFi climb and the employees could use the facilities for meetings and building gear. They could also get anything the wanted from the parts dept at Tek’s cost. They would subtract it from their bi-weekly salary!
If you can’t find anything let me know. I know I have some beautiful Black & white pictures somewhere.
They were professional pictures taken and developed and printed in house by the …..Tek photography club!
Peace,
Rick
I just got done on a job that is making turbine engine parts for a very expensive military program.
I never understood cost-no-object military gear.
Cost is no object for those parts that they produce. I would never beleive it until I saw it with my own eyes. They may make turbine parts in that facility, but what they really make is $$$!
I have an old Tek field service o-scope from the early eighties. It's only got a 3" CRT, but the thing is built like a brick sh*t-house. It fires up with a high contrast sweep from -30F to 104F with no issues.
Great stuff.
It was a very special dishwasher made for cleaning electronics.
I worked in the cal lab at a large Motorola plant from 1974 to 1984. We had one of those machines. It used nonconductive deionized water, a special detergent and also had a 12 or 24 hour bake out cycle for drying. I brought all sorts of "vintage electronic equipment" (junk) into the plant to run through that machine. Wood cabinets and speaker drivers are about the only thing I didn't run through it. I got a beer drenched Univox Mini Korg music synthesizer cheap at a flea market, ran it through the "dishwasher" and it looked and worked great. I traded it in on a better synth at a large music store.
The lab boss drew the line at grimy car parts though.
Hey George, I'm guessing you've been by or know people at the place where I was just working (the place where I learned the true meaning of "cost no object"). I'd rather not call it out by name, but it was just off the bee line highway that runs from WPB to Okeechobee in a city named after a very large satellite.
I am guessing they swapped with or sniped quite a few employees from Motorola back in the day.
I am guessing they swapped with or sniped quite a few employees from Motorola back in the day.
Sounds like the place across the road from the dragstrip that I used to frequent. During a race 20 some years ago we kept hearing explosions, then people began to point to the sky. A test pilot from that place would fly over, nose up into a stall then hit the afterburner launching himself skyward and dazzling spectators at the racetrack with fireballs in the sky.
I knew a few people who worked there especially during the "Starwars defense program" years, but the employees there seemed to be a bit different than the Motorola or IBM crowd I knew. Other than contract workers, movement between IBM and Motorola was somewhat rare. There were even fewer from that place in the swamp. Hamfests and computer shows was where I met most of those people. The government contract world was either feast or famine and it was rare for someone to stay at one place for more than two or four years. Many people in the GC world moved all over the country to follow the work. When the Starwars electrically pumped laser thing died all sorts of neat HV electronics went into the dumpsters and most of the people that I knew there were scattered across the country. I lost track of most of them except for an occasional hamfest meeting. Motorola Florida would go through a similar situation about 10 years later as all of their facilities shut down.
Motorola was one large vertically integrated company until the stock market wizards took over, broke up the company, and parted it out like a junk car. We had the "every penny counts" cell phone development engineering operation and a "cost is no object" public safety radio development group working in the same facility. I did time in both groups. Asking "how much does it cost us to place an SMD component on a board", or "how much does it cost us to ship an empty box" is important in a cell phone design at a million+ unit annual run rate and a sub $200 price to the phone carrier. "What is the best and most reliable component for this slot" is the most important question in a police walkie talkie with a 10,000 unit annual run rate and a $4000+ price to the police or fire department when someone's life may depend on it working. Both products have about the same number of components in them.
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I had to look it up on the Gargler's satellite maps. I didn't realize there was a racetrack across the street, I've never gone northwest of the plant entrance.
Yep, that's the place. I know they made a very dark song bird's engines there and would test them outside.
I've never experienced it, but I'm guessing when an engine starts making "mach-diamonds", things start to get real loud.
I also know this place might be associated with it: https://en.wikipedia.org/wiki/Apix,_Florida
On a personal side note to share my many many thanks with you, here's a story of how I got to where I am today:
I built my SSE when I was 24 (2009) and in trade school to become an electrician. I built it for my final project in my electronics course.
Everyone else turned in some cheap novelty board such as a PCB that would start chirping after fifteen minutes of darkness, and then stop when the lights came on; just a prank to annoy your roommate.
I on the other hand built my SSE (Simple*S*E back in those days, before the stupid trademark BS). The school (dunwoody.edu) was cleaning out the basement when I started the course. The instructor, who had been there since '69, knew I was passionate. He let me look over a box of old tubes they were planning to sell on eBay and take anything I wanted. Metal can 6L6's, Coke bottle 6L6GA's, NOS TungSol 5881's, Coke bottle 5U4G's, ST 5U4GB's... all for free. He appreciated my passion to learn. I wrote down all the names printed on the tops of the boxes and started googling. That's when I found the SSE. It seemed to be a perfect fit for the Tube's that I had access to. I only took what I could use in the SSE.
I had to haul my final project in with a laundry basket; SSE, speakers, portable CD player, and all the cables that go with. I gave my presentation to the class and my instructor, it took nearly two hours of the three hour class with all the different audio samples. I hot swapped between cathode feedback and UL multiple times with no issues. 😳
I wasn't interested in anything when I was in high-school, other than trying to make friends, as I had moved from MI to MN when I was fifteen. I pissed away high-school, the only teacher that ever held me accountable was my AP English 12 teacher. She threatened me that I would not pass and graduate with my peers; I thought she was full of BS and didn't listen. I didn't get to walk across the stage on graduation day with my friends. (God bless you Terry Caruso for holding me accountable!)
Once I completed my remedial make-up course in the summer and finally got my diploma, my parents started to charge me rent. My mother was a librarian for the school district and informed me that the custodial union was hiring and paid well.
After three years of cleaning toilets and other jobs, my now wife, who was my girlfriend at the time, pointed out that I seemed to like the building maintenance part of my job (mostly changing out old PCB filled florescent light ballast), and maybe I should go to school to be an electrician. My old man made me an offer, he would pay 100% for every A, I would pay 100% for every A- and below. It is still the best deal I've ever been offered and ever made.
My instructor said anyone can get an A, he had given out four of them since '69. The SSE netted his 5th. He retired after that year.
I graduated at the very top of my class. I paid $800 for one useless elective that was taught by a guy who's main source of income was reading fortunes at the Renaissance fair each summer. I graduated during the aftermath of the housing bubble collapse. No one was hiring. I was in the top five of over 600 on the waiting list to get on the bench at the electrical union. I spent four months looking for a job, before I went back to my previous school to go through their industrial automation and robotics program. I was hired bu my current employer before I had technically finished the program. Luckily for me, half of my electrical credits transferred over, since a lot of industrial automation is electrical.
I have been a field service technician now for over 11 years. Some of my jobs are not that interesting (stacking boxes on a pallet), some of them are boring but in cool locations (changing robot grease in West Palm Beach, FL), but some of them are amazing (building human-rated flight articles that will go around the moon).
The hardest part of my job is that it takes me away from my two young daughters. But, as I have learned from all the genorosity of the people at diyAudio, I can be with them every day in spirit if I make it a point to teach them something that I have learned that day. Duo video calls help too. 🙂
Tubelab has taught me more about life than tubes.
Thank you George for all that you have shared with this community, most importantly your passion to teach and to excite. My life would be truly different if you did not share your knowledge and passion with me and all of the other wonderful people on this site.
-Phil
Yep, that's the place. I know they made a very dark song bird's engines there and would test them outside.
I've never experienced it, but I'm guessing when an engine starts making "mach-diamonds", things start to get real loud.
I also know this place might be associated with it: https://en.wikipedia.org/wiki/Apix,_Florida
On a personal side note to share my many many thanks with you, here's a story of how I got to where I am today:
I built my SSE when I was 24 (2009) and in trade school to become an electrician. I built it for my final project in my electronics course.
Everyone else turned in some cheap novelty board such as a PCB that would start chirping after fifteen minutes of darkness, and then stop when the lights came on; just a prank to annoy your roommate.
I on the other hand built my SSE (Simple*S*E back in those days, before the stupid trademark BS). The school (dunwoody.edu) was cleaning out the basement when I started the course. The instructor, who had been there since '69, knew I was passionate. He let me look over a box of old tubes they were planning to sell on eBay and take anything I wanted. Metal can 6L6's, Coke bottle 6L6GA's, NOS TungSol 5881's, Coke bottle 5U4G's, ST 5U4GB's... all for free. He appreciated my passion to learn. I wrote down all the names printed on the tops of the boxes and started googling. That's when I found the SSE. It seemed to be a perfect fit for the Tube's that I had access to. I only took what I could use in the SSE.
I had to haul my final project in with a laundry basket; SSE, speakers, portable CD player, and all the cables that go with. I gave my presentation to the class and my instructor, it took nearly two hours of the three hour class with all the different audio samples. I hot swapped between cathode feedback and UL multiple times with no issues. 😳
I wasn't interested in anything when I was in high-school, other than trying to make friends, as I had moved from MI to MN when I was fifteen. I pissed away high-school, the only teacher that ever held me accountable was my AP English 12 teacher. She threatened me that I would not pass and graduate with my peers; I thought she was full of BS and didn't listen. I didn't get to walk across the stage on graduation day with my friends. (God bless you Terry Caruso for holding me accountable!)
Once I completed my remedial make-up course in the summer and finally got my diploma, my parents started to charge me rent. My mother was a librarian for the school district and informed me that the custodial union was hiring and paid well.
After three years of cleaning toilets and other jobs, my now wife, who was my girlfriend at the time, pointed out that I seemed to like the building maintenance part of my job (mostly changing out old PCB filled florescent light ballast), and maybe I should go to school to be an electrician. My old man made me an offer, he would pay 100% for every A, I would pay 100% for every A- and below. It is still the best deal I've ever been offered and ever made.
My instructor said anyone can get an A, he had given out four of them since '69. The SSE netted his 5th. He retired after that year.
I graduated at the very top of my class. I paid $800 for one useless elective that was taught by a guy who's main source of income was reading fortunes at the Renaissance fair each summer. I graduated during the aftermath of the housing bubble collapse. No one was hiring. I was in the top five of over 600 on the waiting list to get on the bench at the electrical union. I spent four months looking for a job, before I went back to my previous school to go through their industrial automation and robotics program. I was hired bu my current employer before I had technically finished the program. Luckily for me, half of my electrical credits transferred over, since a lot of industrial automation is electrical.
I have been a field service technician now for over 11 years. Some of my jobs are not that interesting (stacking boxes on a pallet), some of them are boring but in cool locations (changing robot grease in West Palm Beach, FL), but some of them are amazing (building human-rated flight articles that will go around the moon).
The hardest part of my job is that it takes me away from my two young daughters. But, as I have learned from all the genorosity of the people at diyAudio, I can be with them every day in spirit if I make it a point to teach them something that I have learned that day. Duo video calls help too. 🙂
Tubelab has taught me more about life than tubes.
Thank you George for all that you have shared with this community, most importantly your passion to teach and to excite. My life would be truly different if you did not share your knowledge and passion with me and all of the other wonderful people on this site.
-Phil
The Hydrogen plant and the jet engine test stands are still visible on the satellite photos. I have not been to the racetrack in close to 20 years, so I did not realize how far "civilization" has encroached outward towards the place. If this goes the way things did in Broward County where I lived, the people who move out near a known source of loud sound like the track and the facility will eventually organize and demand that it be moved or shut down. There was a track built on swamp land 10 miles west of anything in the 1960's in Broward County. By the early 2000's it was shut down by the people who moved there. A Cuban grocery store now stands where I used to race my car in the 70's.
I went to a technical high school that had a 3 year vocational electronics program. I got "A's" in all of those classes, and far worse in all of those "useless other classes" that were required, mostly because I was bored or didn't even show up. I started my first pass at college in 1970 when I was already working at a TV repair shop. I was put on academic probation in 1972 with no mathematically possible way to get out, so I got the job at Motorola and quit school. Coincidentally, I had to take some stupid elective class that was taught by a guy who came to class barefoot in bell bottom jeans and a tie tyed t-shirt and sat cross legged in the middle of the teachers desk. A couple years later I saw him. He was a pawn in the human chess match at the local Renaissance fair, still wearing similar clothes.
Motorola convinced me to go back to college twice during the 41 years that I worked there. Their offer was similar, but required a lower level for success. They would pay 100% of tuition and some other fees for a "C" or better. Zero reimbursement for anything below a "C". This time college mattered, so I got all "A's."
My first return to college was for a BS in computer engineering. We had to do two final projects. One had to be an analog design and the other had to be a "digital project" that could involve hardware, software, or some combination of both. I had already put together a team of students who designed and built an autonomous robot car using two MC68HC11 microprocessors for an IEEE student competition where it took second place over many prestigious schools like MIT, VT, Georgia Tech and others. This satisfied the digital project requirement for myself and the other robot team students. We had to do the analog project. The teacher asked us to put together paper describing a simple project, discuss what it would do, and it's measurement criteria. We would then build the project and measure it's performance against the goals that we set for ourselves. We had to present this paper orally to the entire class a week later. As you can imagine there were mostly lame projects with lame goals. I described a car stereo amp with some rather easy to make power, frequency response and THD specs, but stated my measurement criteria to the teacher in front of the entire class that his head would hit the roof of my car on test day.
This was 1993 which was during the prime of my solid state audio years. Other than a few vacuum tube guitar amps, all of my DIY audio stuff was solid state. After all, I worked for a company that made silicon based life forms and gave them to employees just for filling out a sample request form. Many of my early SS projects were clones of every SWTPC Tiger amps made, and this would be similar since I already had plenty of populated boards for the Plastic Tiger and the Universal Tiger lying unused in a box. Master Blaster, as my project would be known used a Universal Tiger to feed a 15 inch subwoofer, and 4 X Plastic Tigers to feed a pair of 6 X 9's and a pair of 6 inch speakers. The only hard part was making the transformer for a DIY SMPS in 1993.
On test day I parked my car, left a CD in the player, cued up to a song that went from silent to full metal racket instantly, turned the volume up full, then shut the car off and went to class. After each student demonstrated their project to the class, the class itself was asked to submit grades on a pre-prepared grading sheet. It is not known if these grades were actually used. The class then moved to the parking lot. I had a CD case in my hand as I opened the car so the teacher did not expect what was about to happen. As he got into the car, I started the engine, which unleashed Master Blaster unexpectedly. Many foul words in a foreign language flowed from the teachers mouth, and I got my "A."
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I also went to Dunwoody in Minneapolis. I took one of their first "Electro-Mechanical Computer Technology" courses and graduated back in '76. It was supposedly a "computer" course, but we had 6 months of radio and TV before we started playing with an old 1962 IBM 1401 computer. I'm sure I probably took a class from that instructor who started in '69 if he's the radio guy I'm thinking of.
Was it Ray?
I don't know that he ever did any radio stuff, but he did do electronics and basic electrical.
I don't know that he ever did any radio stuff, but he did do electronics and basic electrical.
I really don't remember all the names after 45 years. But the guy I'm thinking of was the radio instructor. He had worked for years in radio repair and at stations keeping the transmitters working before Dunwoody. He made me and another student go out a trap door on the roof to fix an antenna once. That clay tile roof was scarry! He told us the roof wasn't so bad compared to climbing up old radio station antennas to replace burned-out bulbs, sheesh. I did have to go through basics before radio, so I probably did have a class with Ray at one point.
These days I have been playing with the "power drive" concept, which I like a lot, when it works. Still, sometimes, just had it again, something happens (generally my mistakes), and the FET gets destroyed, which generally translates into a drain to source short, and the driver B+ at the grid, which is not good.
So the question: did it ever happen to anyone else? What can one do about it? I read that George did quite some tests with mosfets, and that actually the depletion ones have proven more reliable - but unfortunately not available in isolated packages. One thing I will do is order some of the STF3LN80K5 with my next mouser/digikey order.
Thanks!
Erik
So the question: did it ever happen to anyone else? What can one do about it? I read that George did quite some tests with mosfets, and that actually the depletion ones have proven more reliable - but unfortunately not available in isolated packages. One thing I will do is order some of the STF3LN80K5 with my next mouser/digikey order.
Thanks!
Erik
Mouser shows a very small quantity of 10M45 TO-220 in stock today.
A good quantity of TO-92 case DN2540 are in stock; none of the TO-220 types.
I've wondered if the TO-92 LR8N3 might be usable - they are good for about 20 mils, and never seem to be out of stock. I have a dozen or so, but haven't had a need to use them for anything - yet.
Win W5JAG
Good evening everyone,
I've need of a sanity check. I have a transformer 350-0-350 for this project and am looking at using either 5ar4 or gz37 (i've got a few from a loooong time ago). My desire is to push the 300Bs as near to 400v as I can get. I ran the simulation in PSUDII and...well I'm stumped. I 'think' the gz37 shows @ 350v and the 5ar4 @390v. I will attach the psud files here, if someone has a few minutes I would appreciate a 2nd look. I have modded the psu caps for both rectifiers - well kept the stock components for the 5ar4. I think I need to look at the R1 voltage for the B+? I did look at the PSUD stock 5a4 and it showed a value of 392 in R1. Is this a correct simulated reading?
Many thanks
Erick
I've need of a sanity check. I have a transformer 350-0-350 for this project and am looking at using either 5ar4 or gz37 (i've got a few from a loooong time ago). My desire is to push the 300Bs as near to 400v as I can get. I ran the simulation in PSUDII and...well I'm stumped. I 'think' the gz37 shows @ 350v and the 5ar4 @390v. I will attach the psud files here, if someone has a few minutes I would appreciate a 2nd look. I have modded the psu caps for both rectifiers - well kept the stock components for the 5ar4. I think I need to look at the R1 voltage for the B+? I did look at the PSUD stock 5a4 and it showed a value of 392 in R1. Is this a correct simulated reading?
Many thanks
Erick
TSE-2 and mic29502wt substitute
I recently received a tse-2 board from George. Thank you. I’m currently looking for some of the more hard to find parts for this build. I have not been able to find the mic29502wt in stock at the usual places. I’m wondering if I can use the mic29503wt as a substitute? Mouser and digikey seem to have a small stock of this chip. Thanks Thomas
I recently received a tse-2 board from George. Thank you. I’m currently looking for some of the more hard to find parts for this build. I have not been able to find the mic29502wt in stock at the usual places. I’m wondering if I can use the mic29503wt as a substitute? Mouser and digikey seem to have a small stock of this chip. Thanks Thomas
Looks like pin 1 is different between the two chips, but I don’t know enough to figure out if it will still work. Thanks again Thomas
I have not actually tried a MIC29503WT chip, but the data sheet does indicate that pin 1 is the only difference. On the MIC29502WT chip pin 1 is an INPUT that turns on the chip. In the case of the TSE-II board pin 1 is tied to the raw rectifier heater supply which keeps the chip on whenever the board is powered. On the MIC29503WT chip pin 1 is an output which will be very unhappy if it is connected to a high current power source. This could destroy the chip.
It does look like the MIC29503WT chip will work in the TSE-II board if pin 1 is left unconnected by bending the pin upward so it does not get inserted into the board, or by cutting it off.
Again, I have not actually tried this, and I do not have any MIC29503WT chips here in the lab. I'll get a couple next time I order parts, but this might not happen right away.
It does look like the MIC29503WT chip will work in the TSE-II board if pin 1 is left unconnected by bending the pin upward so it does not get inserted into the board, or by cutting it off.
Again, I have not actually tried this, and I do not have any MIC29503WT chips here in the lab. I'll get a couple next time I order parts, but this might not happen right away.
Hi George, Thanks for the info. Hopefully mouser or digikey will get the 29502 back in stock sometime soon. Cheers, Thomas