What's to like right now? Tried to get parts lately? Wood cost's nearly twice what it did a year ago. Semiconductors? Forget about it. You just can't get many current production parts.
I have been working on DIY music synthesizers off and on for years. I have four working DIY digital synths, but "still haven't found what I'm looking for" so I'll keep building....maybe.
ARM Cortex M7 chips, buy now for delivery in November? TDM DAC/ADC chips, I might be able to get a few in August. My last but was at $8 each, today they are $11, but not available. The automotive spec version is $13, and Mouser has maybe a dozen. I ordered 3 for the price of 5. Wee will see if I actually get them.
OK, instead of a custom audio processor that I design myself, I'll just wire stuff up to Teensy boards like I did in my other synths, so I go to PJRC to buy some more T4.1 boards, and they can't get CPU chips either. No boards available. Adafruit has a few, for a $5 higher price.
Oh, well the fancy digital synth is on hold again, back to the analog vacuum tube version.
I have been working on DIY music synthesizers off and on for years. I have four working DIY digital synths, but "still haven't found what I'm looking for" so I'll keep building....maybe.
ARM Cortex M7 chips, buy now for delivery in November? TDM DAC/ADC chips, I might be able to get a few in August. My last but was at $8 each, today they are $11, but not available. The automotive spec version is $13, and Mouser has maybe a dozen. I ordered 3 for the price of 5. Wee will see if I actually get them.
OK, instead of a custom audio processor that I design myself, I'll just wire stuff up to Teensy boards like I did in my other synths, so I go to PJRC to buy some more T4.1 boards, and they can't get CPU chips either. No boards available. Adafruit has a few, for a $5 higher price.
Oh, well the fancy digital synth is on hold again, back to the analog vacuum tube version.
Yeah, the semiconductor shortage has been a huge nightmare. Went to buy OPA1678s, for example. Nope, every distributor is out of stock.
Been fighting with it at work too. Between the time I put in a purchase order and it actually getting ordered, usually 5-10% of the parts on my list become backordered and I have to find subs, or put in another purchase order from another distributor.
Been fighting with it at work too. Between the time I put in a purchase order and it actually getting ordered, usually 5-10% of the parts on my list become backordered and I have to find subs, or put in another purchase order from another distributor.
Octopart found the few CS42448-DQZ high spec codecs at Mouser. No lower cost CS42448-CQZ's.
They can't find me any MIMXRT1062DVJ6A (orDVJ6B) ARM chips though....
Lots of other small semiconductors are also MIA, and what shows "in stock" may not really exist when the order is placed. I have not yet heard from Mouser about my chip order.
Can't find any of the Bourns rotary encoders that have the RGB LED built in. I do have some Chinese clone encoders back ordered from Sparkfun. Maybe I'll get them next month, maybe next year.....
They can't find me any MIMXRT1062DVJ6A (orDVJ6B) ARM chips though....
Lots of other small semiconductors are also MIA, and what shows "in stock" may not really exist when the order is placed. I have not yet heard from Mouser about my chip order.
Can't find any of the Bourns rotary encoders that have the RGB LED built in. I do have some Chinese clone encoders back ordered from Sparkfun. Maybe I'll get them next month, maybe next year.....
board.
I remember trying to add a TQFP package to my CAD library in the software I wrote.
So I used the component wizard and put in all the parameters.
Looked fine so got pcb's made.
Came to solder IC and pads slowly get out of alignment as I went along.
Turns out the distance between pads was losing resolution and this accumulated causing the errors.
I rewrote the pad generator to use a multiple of original spacing instead of adding spacings and losing resolution. Worked out fine.
Of course if I had printed out component to start with I would have seen the problem earlier.
So I used the component wizard and put in all the parameters.
Looked fine so got pcb's made.
Came to solder IC and pads slowly get out of alignment as I went along.
Turns out the distance between pads was losing resolution and this accumulated causing the errors.
I rewrote the pad generator to use a multiple of original spacing instead of adding spacings and losing resolution. Worked out fine.
Of course if I had printed out component to start with I would have seen the problem earlier.
When you remember that one extra critical part that you needed to order, but you already hit the 'order now' button and the free shipping minimum will cost another $60.
Then spend the rest of the evening scouring the categories for stuff you don't need, just to get that free shipping.
Or maybe that's just me
Been there done that one a few times too many.
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That's familiar as is choosing the postal service as the low cost shipping option and watching the missed part disappear into the twilight zone.
Realizing the footprint you made is correct and the symbol you made isn't having routed those pins on internal layers out of reach; discovering this after soldering hundreds of expensive SMD parts on the boards, and discovering they were unsalvageable. (22 reed relay coils swapped with the contacts.) Fortunately I like laying out PCB so I just treated it as an opportunity after I got over the initial shock. (my biggest and only unsalvageable PCB layout mistake)
Realizing the footprint you made is correct and the symbol you made isn't having routed those pins on internal layers out of reach; discovering this after soldering hundreds of expensive SMD parts on the boards, and discovering they were unsalvageable. (22 reed relay coils swapped with the contacts.) Fortunately I like laying out PCB so I just treated it as an opportunity after I got over the initial shock. (my biggest and only unsalvageable PCB layout mistake)
Similar to Kevin's experience, the part where you get a wild idea, input the schematic, lay out he board, make the board, drill the board, and populate the board.
Then you hook it up to the test equipment, fire up the 60+ year old Fluke 407D power supply, wait for it and the heater on the test board to get good and warm. Then you turn the HV on switch on the power supply to see the fire gods descend on your board and dance in anger all over it destroying most of the silicon on the board.
At this point you rip it out by the wires and toss it violently across the basement into a concrete wall where the tube shatters and all falls to the floor below.
After a few days of cooling off, me not the glassless tube, I perform an autopsy to realize that I had swapped the layers when I made the board so that everything was mirrored. All silicon based life forms were in backwards, and the tube had it's pins reversed. Electricity went places it wasn't supposed to go.
I tossed it into the trash in disgust, then later retrieved it to try a dumm blonde experiment. This picture shows the result. I put a second tube socket on the other side of the board, replaced all the silicon, putting it on the other side of the board as well. It was ALIVE!
This board turned out to be the light bulb that finally lit up my brain to the UNSET / CED technology that's making 20 to 40 watt SE amps from a single TV sweep tube possible. It had a pair of mosfets on the cathode, G1 and G2 so the any or all of these elements could be driven in either phase, and sink or source current at any offset voltage. Once the bulb went on, I made a new board with far less parts, and this one was retired to the box of spare parts.
Sometimes even screw ups that survived being smashed into the concrete wall can turn out to be a learning experience.
Then you hook it up to the test equipment, fire up the 60+ year old Fluke 407D power supply, wait for it and the heater on the test board to get good and warm. Then you turn the HV on switch on the power supply to see the fire gods descend on your board and dance in anger all over it destroying most of the silicon on the board.
At this point you rip it out by the wires and toss it violently across the basement into a concrete wall where the tube shatters and all falls to the floor below.
After a few days of cooling off, me not the glassless tube, I perform an autopsy to realize that I had swapped the layers when I made the board so that everything was mirrored. All silicon based life forms were in backwards, and the tube had it's pins reversed. Electricity went places it wasn't supposed to go.
I tossed it into the trash in disgust, then later retrieved it to try a dumm blonde experiment. This picture shows the result. I put a second tube socket on the other side of the board, replaced all the silicon, putting it on the other side of the board as well. It was ALIVE!
This board turned out to be the light bulb that finally lit up my brain to the UNSET / CED technology that's making 20 to 40 watt SE amps from a single TV sweep tube possible. It had a pair of mosfets on the cathode, G1 and G2 so the any or all of these elements could be driven in either phase, and sink or source current at any offset voltage. Once the bulb went on, I made a new board with far less parts, and this one was retired to the box of spare parts.
Sometimes even screw ups that survived being smashed into the concrete wall can turn out to be a learning experience.
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Right now, the part of DIY I hate is not being able to do any of it!! I'm so busy with actual day-job stuff (and so damn disorganized in general), there doesn't seem to be enough hours in a day anymore. Got some pretty cool projects (for me anyway) gathering dust. I need to figure out some way to start folding this stuff back into the schedule; I miss it.
I'll be turning 69 years old in a few weeks. I have come to realize that I have more projects started or planned than life expectancy, so some have got to go.
I still have that monster SE OPT, the power transformer, and some 833A tubes from the 200 Watt SE guitar amp proto that was used for my Avatar picture. UH that was from about 15 years ago. Guess I'll never build it.
Got enough parts to build not one, but two 1 kilowatt (500 WPC) stereo tube amps. Maybe I'll build one. Or maybe not.....what would I do with a 1 KW tube amp?
I have recently realized that it has been almost 10 years since I actually completed an amplifier build.
I have begun the process of making a list and weeding out the projects that really don't matter. As this list takes shape you will see some parts, some unfinished amps, and who knows what on the forum swap meet. What doesn't sell there goes to hamfests (If they still do them) and then Ebay.
George’s gargantuan garage sale
That already happened over 7 years ago.
My 41 year engineering career came to an end on April 1 2014. I had known that the end was in sight for years when the Wall Street Wizards took over control of the company, busted it up a started selling off the parts like a junkyard does with a useless old car. For years prior I hit the hamfest circuit selling stuff, or trading big things I didn't use for small things that I might use. I had pruned my tube collection from well over 100,000 tubes to around 10,000. What didn't sell at the big Dayton Ohio hamfest was stored in nearby West Virginia effectively moving it in advance of the inevitable.
We had begun an orderly migration out of Florida to our retirement location 1123 miles north. Yeah, I know everyone else does the reverse. The plan was to put the house up for sale for far more than it was worth using a rookie real estate agent who had a leased Jag, an iPhone, and a rent-a-space office, but offered a serious discount on the commission.
We planned take our time moving with a box trailer on my Honda Element and Sherri's SUV driving stuff north and stopping for fun along the way. We took 11 trips this way over several years, but decided to start renting box trucks once I didn't have a job. Before the first 26 foot box truck was completely unloaded in June, I got a phone call from the real estate guy explaining that he had a cash offer on our house at the asking price, but we had 3 weeks to be out of a house we had lived in for 37 years. We were 3 days late, left on July 3rd.
A full scale panic set in and every day was a garage sale. We had two large PODS moving boxes in the yard and anyone who helped us load them got free stuff. I sold, gave away, and in some cases trashed over half of my "stuff" since we had to find storage for everything we actually moved because construction on our new house had not yet started.
I gave a rare vintage guitar amp worth about $1K to another member of this forum, sold a working Bandmaster for $200, and traded several hundred tubes for a guitar. Even with deals like those over 1000 pounds of transformers went to the metal scrapper, as did some of my exercise equipment.
The plan to organize stuff and label each box turned into "what can we stuff into each moving vehicle, and how many transformers will it take to put this box truck 50 pounds below max GVW." The big yellow rental trucks will be weighed on the road and must be under 26,000 pounds. You go over and you are taken off the road, and probably fined. The truck can not move from the weigh station until it is made legal. I had one weigh ticket at 25,970 pounds with me in it.
Many years ago I made a technical contribution to a primer covering basic maintenance and repair of dirt bikes and ATV's.At least holemounted ICs can be easily found walking around barefooted ...
The principal author and I came to a consensus on what the book would open with. It was a list of basic tenets to follow when doing the work.
Rule #1: NEVER kneel on a screw, no matter what size it may happen to be.