gmoon

Hi Mike. Sorry about the late reply. I checked Ibles only a week or so ago, and didn't see your post (? who knows).Cool, I see you built from scratch using the Silvertone schem. I don't doubt the tubes can take a bit higher voltage than spec'ed. I think they were all +- 10% back then, and many could be abused further. I don't think you'll have any problems at all with the resistors.Working on replacing the baffle board of my Silvertone 1482 today...Good luck and rock on.

Awesome -- you are welcome!

This project was all done by hand...it can be done!

Totally look at the brushes, as everyone posted.We had some tile guys at our house who used my cheapo Harbor Freight grinder to cut cement board, and the grinder stopped working. The brushes were fine, but it turns out if you overuse/overheat the tool, the springs that hold the brushes loose temper, and stop being "springy." Could be as simple as that...

Have you looked at old-school 7-segment LEDs with "retro" BCD (Binary Coded Decimal) shift registers? I'd imagine any modern register would still do BCD anyway, Steve's MAX7221 (or that SN74HC595) would (or make your's hex for a change..). Should be loads of info on that stuff online--and it's a only a (temporal) step removed from nixie tubes...'Course I can see why a hacked LED display might be a fun project...When I was a kid, my cousin worked for Wang electronics, and brought home an early calculator they made -- with nixie tubes, a punch-card reader and 64 bytes of memory! Wow, that makes me old...

Wood stain (try different colors) and a coat or two of varnish?Kinda like most wood projects...

Seems like it's very implementation dependent. A skateboard has tilt designed into the steering (like some three-wheel motorcycles) so that would have a non-trivial effect. Would your design not tilt due to the side car?My cousin, BTW, owns a Ural sidecar motorcycle. Both back wheel (the bike and the sidecar wheel) are drive wheels. They are locked together without a differential -- but the dang thing still works fine. I think the newer models can on-the-fly switch between one and two-wheel drive...

Thanks! Good point...

We moved in last year to a home with a heat pump and a four zone control system. It uses pneumatic dampers, and I'm sure they weren't cheap for the last home owner. And they aren't foolproof. Or necessarily balanced. Always seems to be issues to iron out. We are getting there tho...A search for "5'' hvac damper" seems to return several options between $6 and $15 USD, for the manual type. I recently installed a 6'' manual one on one of our ducts that had no damper at all (who knows why they did that??? For a basement room). It's a pretty easy install if you can get to the duct work.The zone style dampers (controlled remotely) run anywhere from $62 to $175 USD. Not inexpensive.This post is 1 1/2 months after the OP. Sorry.

Silliest thing Instructables ever did was to fragment their user community into forum users and "Answers" users. Although the overall community never was very interested in interacting outside of their individual projects.Coming from a long-time I'ble-er...

I haven't used Illustrator for awhile, but I do use Lightroom CC and Photoshop CC practically every week.All Adobe products seem to share a common interface for preferences. Go to Preferences -> Performance and check on Memory Usage. Maybe it's set to low memory usage...

I'm not conversant with RTOS, but Lists and Queues are ATDs -- abstract data types. They differ in how the data can be accessed.A list datatype (or object) offers a number of functions for accessing data. A List can traversed (forward or backwards), accessed by index #, sorted, etc. A queue is a first in-first out datatype. The functions for each datatype will vary by language, of course. If RTOS uses them for task interfacing, then the choice will be dependent on how the programmer wishes to access the tasks.

Maybe. If you can find the signal path before it's amplified.If you're working directly with the (low impedance) signal connected to a speaker, it probably requires an attenuator (rheostat) rather than a volume control. I'd expect the driving power on a small device to be somewhere around a watt (give or take 150%). A rheostat is electrically the same as a volume control, but can handle more wattage.I suggest you look up the "Cracker Box Amp" from Make mag, it uses a 25 ohm, 25 watt rheostat (which once was available from Radio Shack, but no more, I think), for a 386 chip amp that outputs about a watt.But you can make one from fixed resistors, clearly the little 1/8 watt resistors aren't gonna cut it with a one watt output. But 2W to 5W resistors are probably fine.For resistor...

Maybe. If you can find the signal path before it's amplified.If you're working directly with the (low impedance) signal connected to a speaker, it probably requires an attenuator (rheostat) rather than a volume control. I'd expect the driving power on a small device to be somewhere around a watt (give or take 150%). A rheostat is electrically the same as a volume control, but can handle more wattage.I suggest you look up the "Cracker Box Amp" from Make mag, it uses a 25 ohm, 25 watt rheostat (which once was available from Radio Shack, but no more, I think), for a 386 chip amp that outputs about a watt.But you can make one from fixed resistors, clearly the little 1/8 watt resistors aren't gonna cut it with a one watt output. But 2W to 5W resistors are probably fine.For resistor values, use the speaker impedance as a guide -- an 8 ohm speaker won't require resistance values much more than that (which is why the rheostat in the above project is only 25 ohms).As to why a std volume control (POT) probably won't work, they are usually 1/4 to 1/2 watt. If you can find one that's rated for 2 watts, that might work. But it's gotta be a very low resistance value to work with a low output impedance. Even a 1K pot will barely have any useful range. Again -- it's why the above rheostat is 25 ohms.

I've bought them from Tayda, online. If the shipping is mucho, buy as much at one time as you'll need for years. Most discrete transistors used for guitar projects are designated "obsolete" now, and won't be available in ten years anyway (or will be at crazy prices), so it's a good time to stock up.

The chip is fried, or it doesn't sound good?The LM386 should be OK with up to 12VDC. Are you sure the Roland unit is DC? If so, is the polarity correct? Have you tried the LM386 setup alone? (nothing else daisy-chained?)

Those values (replacing 220 ohms with 1K) are in the power supply itself, which is chained to get different voltages. Look at the PS schematic rather than the preamp. I.E., it's before the the plate resistors. Sorry I didn't see this earlier. We've been in remodel mode for 6 months...

"Let the buyer beware" is an old adage. It's been estimated that constructing a car from OEM parts gets you the same car...for three times the $$$. Parts generally need to be priced higher to pay for inventory costs, etc. Just how much higher is the question.Of course, with this internet thingie, it's sometimes possible to find parts MUCH cheaper. That's often hit-and-miss, though. And ebay/amazon prices are extremely variable for the same item. Availability is extremely variable, too. I rebuilt a 1985 Tecumseh carburetor last year for about $15 USD in parts. Had it been a newer model, an entire replacement carb would have cost only $14 (my older one could be found for ~$90). Cost/availability brings up some real ethical questions. We've been remodeling a house since July last...

"Let the buyer beware" is an old adage. It's been estimated that constructing a car from OEM parts gets you the same car...for three times the $$$. Parts generally need to be priced higher to pay for inventory costs, etc. Just how much higher is the question.Of course, with this internet thingie, it's sometimes possible to find parts MUCH cheaper. That's often hit-and-miss, though. And ebay/amazon prices are extremely variable for the same item. Availability is extremely variable, too. I rebuilt a 1985 Tecumseh carburetor last year for about $15 USD in parts. Had it been a newer model, an entire replacement carb would have cost only $14 (my older one could be found for ~$90). Cost/availability brings up some real ethical questions. We've been remodeling a house since July last year, and have literally been to (or researched) almost every supplier -- from Home Depot/Lowe's/Menards/Lumber Liquidators/supply houses/etc., all the way down to dollar stores. One thing is obvious -- if you can't afford to buy in quantity (or don't have transportation), the worst prices will be at the dollar/discount stores (like $5 for a single CFL bulb, vs four LED bulbs for $6.50 at a supply house).

It should be OK. (sorry for the delay)

We lost multiple devices (TV, router, switch, computers, even low-voltage track lighting) in a lightning strike a few years ago. Most of it was unsalvageable.The only guidance I can offer is to physically disconnect (I.E. unplug) stuff, including any TV cable or internet. Or just roll the dice and hope it doesn't happen.

This year our region saw the return of the Cicada (several periodical species) sometimes known locally as the "17 year locusts." They crawl out of the ground, climb trees, molt (leaving the old exoskeleton behind), mate and die after only a few weeks. They make quite a racket while they are here.Freaky looking, mostly due to those red eyes.

That is one beautiful weld on the top of the tank!

Yeah, I definitely want to learn the solid core/gas stuff, ASAP, too. Thanks for the inspiration!

Dang! I bought the same (Handler 140) welder four months ago! But we also bought a new house in July, so my days are filled with painting, plumbing, wiring, etc., etc., not happy welding projects. Still haven't the Hobart! I figure I'll start with the flux core first...looks like you're already using gas (jealous).

Oops. Used. haven't used the Hobart.

Sorry, I don't know. Steel is WAY harder than lacquer, and I imagine that power equipment is the best way to proceed.

My bad for not answering sooner -- busy!Not really with one additional 35w4 -- those are single diodes (fine for half-wave). A true bridge is four diodes. Tube amps with full rectification do so with an expensive trick: they use dual rectifier tubes (5y3, 5u4G) together with a center-tapped HV transformer (like 300V,0,-300V). The voltage swings positive & negative around that center tap, and half the available voltage is dropped -- i.e., end-to-end on a 300,0,-300 PT, the full voltage swing is 600V! (and the output would be 600V with a standard SS four-diode bridge).They did this because :A) they absolutely knew full wave was better.B) Iron and copper were once much cheaper than tube rectifiers. Now the opposite is true -- metal is expensive (and heavy) but sand (silicon) semiconduc...

My bad for not answering sooner -- busy!Not really with one additional 35w4 -- those are single diodes (fine for half-wave). A true bridge is four diodes. Tube amps with full rectification do so with an expensive trick: they use dual rectifier tubes (5y3, 5u4G) together with a center-tapped HV transformer (like 300V,0,-300V). The voltage swings positive & negative around that center tap, and half the available voltage is dropped -- i.e., end-to-end on a 300,0,-300 PT, the full voltage swing is 600V! (and the output would be 600V with a standard SS four-diode bridge).They did this because :A) they absolutely knew full wave was better.B) Iron and copper were once much cheaper than tube rectifiers. Now the opposite is true -- metal is expensive (and heavy) but sand (silicon) semiconductors are (literally) dirt cheap! Plus there was always a trade-off regarding current draw of the tube filaments, and double the rectifier filament current wasn't deemed acceptable.Full rectification end-to-end is very do-able with two dual-rectifier tubes. I'm sure it's been done.

"I stick my hands in fans..for fun."

Older, anyways. And I'm way past that moment.

This dates me. Look to the 3:47 mark: https://www.youtube.com/watch?v=FeZlXJtLhMQEugene, by Crazy Joe and the Variable Speed band (Ace Frehey).

You might look at a "Tube Screamer" schematic, which uses diodes in a feedback loop, for "soft clipping."

A good ol' unmodified microwave transformer should have one secondary with HV (~2000VAC).

That's it!

Look online for the Gibsonette schematic. The later versions were parallel single ended like this, but with 6v6's.But a 6v6 push-pull topology might be worth exploring, if it's a two tube 6V6 output amp is you want (like the classic Fender Deluxe). It would be louder, and the output transformer would be even easier to source.

If streaks remain, it probably wasn't rubbed out enough at the end (as it drys). Or maybe you used a little too much...

Hi -- hope I can help.You can use the wet/dry paper dry (why they call it wet/dry!), even though I usually use it wet. The wet technique probably makes it easier; lubricates the paper, keeps dust from clogging it, etc. Wet, it can be tricky to not sand through your finish layers, though.It's important to progress up through the finer grades of paper. I would want to prep a fine finish with over 1000 grit, wet. Probably 1200 to 2000 grit is a good idea. And sanding alone won't do it. Rubbing compound is a must, and you're using that. I've not used every type of rubbing compound out there. I cannot guarantee they all work the same, yet I was able to develop a "feel" for it's use, and that final bit of physical resistance seemed to be where the compound did the most work. Also, i...

Hi -- hope I can help.You can use the wet/dry paper dry (why they call it wet/dry!), even though I usually use it wet. The wet technique probably makes it easier; lubricates the paper, keeps dust from clogging it, etc. Wet, it can be tricky to not sand through your finish layers, though.It's important to progress up through the finer grades of paper. I would want to prep a fine finish with over 1000 grit, wet. Probably 1200 to 2000 grit is a good idea. And sanding alone won't do it. Rubbing compound is a must, and you're using that. I've not used every type of rubbing compound out there. I cannot guarantee they all work the same, yet I was able to develop a "feel" for it's use, and that final bit of physical resistance seemed to be where the compound did the most work. Also, it's common to use toothpaste as a rubbing compound (Crest?), and I've used that on cars and it does work, too.The final hi-gloss comes from polishing. Rubbing compound wasn't the last step. I use the jeweler's rouge, but there are other types of polishing compounds -- undoubtedly some of those will come in liquid or paste form. The rouge I use is stick-form. I've even used some 3000 grit sanding gel, just because I found some on closeout.My only other thought now would be to be careful about over-sanding on edges and raised details, because that's always a danger.Good luck!

Similar bug has infested the regular forums for years. An old posting will appear between current ones. One year old, eight years old, etc. It comes and goes.Believe I've posted a bug report on it, too. Still have the screenshots...

Look at both Spectra and Dyneema cordage. These are proprietary fabrics similar in strength to Kevlar, but cheaper and with different (lesser) resistance to heat. They definitely come in <5mm diameters.This stuff is common in climbing and other outdoor gear. Other than online, you might find it in an climbing or outdoor outfitter shop...

The input resistors prevent interaction between the outputs (you are mixing together). "Crosstalk" is a good word for it (kudos to Downunder35m).If you really want to understand it, you'll need to learn something about both output impedance and input impedance of audio stages. It tends to be somewhat difficult to get a handle on...Output impedance can be thought of as "signal strength" or the amount of (apparent) resistance present, i.e., between the output and next channel. A low output impedance is generally best. I.E., low output impedance means there is plenty of current available to drive the next stage.Input impedance can be though of as "the amount of load placed on the incoming signals" by the next stage. A high input impedance is generally best. I....

The input resistors prevent interaction between the outputs (you are mixing together). "Crosstalk" is a good word for it (kudos to Downunder35m).If you really want to understand it, you'll need to learn something about both output impedance and input impedance of audio stages. It tends to be somewhat difficult to get a handle on...Output impedance can be thought of as "signal strength" or the amount of (apparent) resistance present, i.e., between the output and next channel. A low output impedance is generally best. I.E., low output impedance means there is plenty of current available to drive the next stage.Input impedance can be though of as "the amount of load placed on the incoming signals" by the next stage. A high input impedance is generally best. I.E., a high input impedance means the input doesn't load down the incoming signal. These are general guidelines only -- speakers, a legitimate "audio stage" have very low input impedance and obviously they interact greatly with the previous stage (hint: all the power needed to move the speaker cone has to come from the previous stage -- they are passive devices!)How those resistor are chosen for the resistive mixer stage depends on what comes next. Is it a high impedance Op Amp? That's usually a good choice. A simple common-collector binary junction transistor amp? Not so great. Low input impedance usually results in both signal loss and loss of high frequencies... There isn't a "law" here, other than a fairly well understood interaction between the two types of impedances.If your audio sources are significantly different levels, you might want to create custom channels for each. Or replace them with POTs.Using caps and decoupling might be needed, but it might not. Depends on the outputs you are using.Impedance, BTW, is just a fancy word for "AC resistance" -- because audio is AC, and the "apparent resistance" resulting is greatly effected by inductance and capacitance, which is a big part of signal processing.

I'm not sure about that, as an explanation. But I'm not certain it's wrong, either, depending on how the auto painter was using the language, etc.This is how I think about it (I was trained and worked as a photographer for 35 years). There are basically two types of reflectivity (although everything is a mixure of both):-- Diffuse, which is the pigment itself-- Specular, which is the surfaceA glossy black and a matte black may have identical pigments, but the glossy paint will always appear darker (actually, have a wider range of contrast), except when the surface is reflecting a large light source. In that case, the pigment beneath a glossy surface is washed out by the other light source. Think of watching a big-screen TV with a picture window right behind you. The reflection makes it ...

I'm not sure about that, as an explanation. But I'm not certain it's wrong, either, depending on how the auto painter was using the language, etc.This is how I think about it (I was trained and worked as a photographer for 35 years). There are basically two types of reflectivity (although everything is a mixure of both):-- Diffuse, which is the pigment itself-- Specular, which is the surfaceA glossy black and a matte black may have identical pigments, but the glossy paint will always appear darker (actually, have a wider range of contrast), except when the surface is reflecting a large light source. In that case, the pigment beneath a glossy surface is washed out by the other light source. Think of watching a big-screen TV with a picture window right behind you. The reflection makes it difficult to see the image. Viewing angle matters.Certainly glossy photographic prints have a greater tonal range than matte prints. Matte, however, tends to hide surface defects. How you light glossy surfaces becomes an art form itself...(it's always about light; we don't see things, we see light bouncing off things).I do think how (and how well) the clear bonds to the paint pigment can have an effect also, but the surface of the completed work has a larger effect, IMHO.Auto paint guys and commercial painters in general may have different opinions (especially about the "depth" of a finish, which is usually a proprietary thing), but that's how I break it down. Hope that helps...

The paint was sanded where repairs were made to the original finish, then a little prep sanding was done overall before the clear. Between clear coats, some wet sanding was done due to "orange peel" effect, when it was needed -- not after every coat.Any major scratches need to be dealt with before clear, of course.

Absolutely, diverse "alternative" sources are a great idea. Let's make them not alternative in the future...However, for a small-scale system, batteries are usually the "glue" that insures clean, uninterrupted power. They act as a reservoir of current when the green power sources, wind, solar and water, fluctuate. Having a buffer (and charging regulators for each) holds it all together. Yeah, batteries are expensive, and yeah, they don't last forever.Trad fossil-fuel generators need to maintain fairly strict RPM requirements, not only for voltage but also for frequency -- which is often more of an issue than voltage stability for electronics. Using inverters and batteries eliminates those issues.Of course every DIY system is unique, and some sites may have unique nee...

Absolutely, diverse "alternative" sources are a great idea. Let's make them not alternative in the future...However, for a small-scale system, batteries are usually the "glue" that insures clean, uninterrupted power. They act as a reservoir of current when the green power sources, wind, solar and water, fluctuate. Having a buffer (and charging regulators for each) holds it all together. Yeah, batteries are expensive, and yeah, they don't last forever.Trad fossil-fuel generators need to maintain fairly strict RPM requirements, not only for voltage but also for frequency -- which is often more of an issue than voltage stability for electronics. Using inverters and batteries eliminates those issues.Of course every DIY system is unique, and some sites may have unique needs and solutions. If the voltage and frequency requirements are "loose," other choices may hold sway...

Awesome, thanks. Make something cool!