For RF work with levels below 100 mV I prefer my TEK 453 CH1 output because it amplifies the input signal and can then trigger my counter on signals too low to do it normally, my 465 does not do this and I have to lower the input attenuator to below 20mV/dev before it triggers my very sensitive TTI counter.
I had a Coco 2 with 64K Ram in the 80s for many years. Then a chip overheated for some reason and I was unable to repair the computer at that time. I regret I threw it to the garbage during the 90s. 😢
I had a Coco 2 with 64K Ram in the 80s for many years. Then a chip overheated for some reason and I was unable to repair the computer at that time. I regret I threw it to the garbage during the 90s. 😢
Time Index ~3:37: Um, we most certainly DID have UHF channels back in 1985! LOL!!!!!! The reason there are only 12 buttons is because those are PRESETS - if you lift the top cover there are tuning knobs inside to let you assign the preset buttons to an actual RF channel.
There is absolutely nothing about the PIC series that lines up with what you said. There isn't a single multi-threaded PIC that I know of, they're programmed using C/C++ just like any other micro, and they are programmed using inexpensive programmers like the PICKit and the MPLAB Snap. If you *choose* to, you can program them in assembly, but just like with any microcontroller there's no requirement to. The PIC32MX line, in particular, is very nice, many peripherals are mappable to different pins (just like many of the 8/16-bit PICs all the way from the PIC10 to the PIC24). The IDE is really easy to use, freely available and has great debugging features. If you're going to dislike something, at least get your criticisms right ;) I've used PICs, AVRs, MSP430s, and ARM Cortex-Ms of all shapes and sizes, and they're all roughly the same when you get down to it. Some prioritize different features like ultra-low power consumption (the MSP430s are great for that), some feature the latest and greatest Cortex-M7 with floating point unit, crypto accelerator, nested vector interrupt controllers, powerful DMA, tons of flash and RAM, and high clock speeds. And some prioritize being the smallest, tiniest microcontrollers, like the PIC10 series and the ATtiny4/5/8/10 which both come in SOT-23-6. Yes, an entire microcontroller in a SOT-23!
Thanks for the informative video. I have a dead 3325A awaiting my attention. By the way, I would be wearing my anti-static wrist strap and have the unit placed on an anti static mat, for these repairs.
What a beautifully researched video. I especially enjoyed the assembly-language walkthrough. You made it very accessible, and the cleverness of the pseudo-binary-search algorithm comes through in your explanation.
I bought, found, collected lots of RS stuff. From this catalog I have the big boom box with the large meters (GE) the watt meter. The second lower priced mixer. Reel to reel take up reel. One of the portable radios. One of the equalizer boosters for the car. Bunch of other stuff from different years. All car audio was pretty trash back then. Most radios 7 to 15 watts max, and speakers were junk unless you spent big money and even still they were nothing like you get today.
Unusual to find 74LS chips in a '60s vintage scope. It probably has something wrong with the power supply. But just blindly replacing all the capacitors is not a good idea. I have been fixing test equipment for several decades and always trace the problem down to the component level. With US manufactured test equipment I have not found many shorted or otherwise defective capacitors. You are more likely to replace good caps with low quality caps that will fail soon if you blindly replace all the caps. What often happens with the Tektronix 7000 series power supplies is a cap or rectifier will fail in the secondary circuit. The power supply will shut down immediately due to the over-current. After about 100 mS., it will start up again. So you will here a tic-tic-tic sound. To fix it, just carefully unsolder and lift a lead from each secondary cap until the tic noise stops. That last cap is the one you replace. Try to find a high quality Japanese cap.to replace it with. Do your repair work to the same standards as originally manufactured.
The I/O ports were memory mapped, which was an interesting difference from the x86 CPUs. On the Coco you would read/write a memory location to recieve/send data to a device, using the load/store instructions instead of dedicated in/out instructions.
Interesting results. I'd love to see the same tests in assembly. Actually, testing the 3 most popular 8-bit CPUs, Z80-6809-6502 toe to toe at the same clock speed would be interesting indeed.
In my experience with a lot of Minimus-7s, the ones in the wooden case (Minimus-7W) are typically better than the ones in the metal case. In fact, I still use a set of 7Ws with my desktop computer. I replaced the capacitor in the crossover with a poly cap and it made a world of difference. But what you really need to look for is where the speakers were made. Radio Shack sourced the speakers from different OEMs during their history. The best ones were made in Japan and are the oldest, more than 40 years old now. Later on, they came from Korea. I've worked on both, but the set I kept was a pair of 7Ws from Japan, made in 1982. Found them on eBay for $25 and they sounded decent right of the box, and great once I swapped out the tired old caps on the crossover. I was listening to them the night the woman who later became my wife visited to borrow my laser printer. Fast forward 12 years and they're still doing the job, running off a K3118 digital amp these days. And my wife still has me play music off them sometimes...
I have one of these (It's the "B" model, but the basics are the same) that my dad used for years in his computer tech job. This has been a handy walk through the controls! I have downloaded a manual, but would love to get my hands on a paper copy...been watching eBay.
Hi there. I just watched your video. Nice job. I was wondering, I am 55 yrs old and always liked electronics since high school shop class where I learned a lot and still remember it. I want to learn to use this animals just for small type repairs I can do myself to maybe fix some audio amps I have. Also what course if I went that rout would I need to take to learn about this unit? Conestoga collage here as I am in Ontario can. I see you are also from Canada THANKS.
Everything you said about the 1.2MB floppy backwards compatibility with 360k disks is correct, however the 1000SX doesn't support the use of high density floppy drives at all - so it wouldn't work in this machine whatsoever even with 360k disks
So.. you should get a Coco, if you need a more powerful computer.. 😄The issue with assembler wasn't the complexity, it was more the lack of an 'IDE' and the risk to lost the content of the memory (source-code) after every simple bug.
Feeble. For a = 1 to 1000 Print a, a*a, sqrt(a), 1/a Next a Ignore scroll speed by not PRINTing but by assigning count, square, square root, and reciprocal to variables. Let us know who wins.
I have an HP 1740a analog scope it does not have exactly the same controls as the tektronix could you possibly do a video explaining how to use the Wade function on that scope or know someone who does thank you
21:10 "What kind of dork would go into a lecture with a big cassette player?" LMAO!!!! I had to pause I was laughing so hard at that. "Dork" is such a 80's insult - even the vernacular is period correct.
Thank you for the introduction to this scope. I was given one as a gift, but I’m used to modern mixed signal digital scopes. Sadly, my 465 just popped the GFCI, so I have to diagnose and maybe get the internal power supply caps replaced.
I had a Model 4 in 1982, I know because I had it before we moved to a new house. Mine was upgraded to 128 k and three floppy drives, couldn’t afford the hard drive. Mine had the black and white screen. I also had wide dot matrix and daisy wheel printers.
The plastic bits that hold the PCB to the chassis are known as drive rivets. A version of them are used extensively in the semi-trailer industry to secure plyliners (the plywood panels that protect the side posts & panels on the inside of the trailer) to the walls of the trailer. You also find tons of them holding various bits of car bodies together with removal typically equally frustrating.
Replace the huge cap with a new Nichicon one - $4. The new ones are about 1/2 the size. You can also replace the 245s with modern 645s which are direct replacements.
I upgraded my CoCo 1 I bought off eBay broken, and replaced 40 parts at once, but still no dice. Black screen. But all the power parts are working fine.
