#Power Supply

[fuzzkaizer]

vintage homemade stompbox pedals -

"pulled from a pedalboard that was made on either the late 60s or early 70s"

cred: reverb.com/The Guitar Shed

#DIY #family #reverb #Gibbs #spring reverb #power supply #mystery pedal

[nestedneons]

By gsd__studio

#nestedneons #cyberpunk #cyberpunk art #cyberpunk aesthetic #cyberpunk artist #art #megacity #cyberwave #futuristic city #cryptoart #power supply

[techav]

So I have this printer ...

Not that one specifically, that one is beautiful and in great condition, but one like it — Apple ImageWriter II. Specifically mine is the ImageWriter II/L variant, the last revision of the ImageWriter II line, but it looks like this one.

Or at least it did once upon a time.

My family acquired this printer second-hand in the late 90s along with a Mac Classic. It got used regularly for school reports and letters and business documents and tax forms for a few years until we finally were able to get a new computer with a color inkjet printer.

Long story short, like the computer that went with it, ultimately this poor printer ended up sitting in storage without air conditioning in East Texas heat and humidity for nearly twenty years. It's a sad story of slow decay.

My ImageWriter is now yellowed and scuffed and scraped and rusted and missing a piece or two; just a dim reminder of its former beauty. Given the state of it, what hope do we have of ever again hearing it sing the song of its people?

Well, I'm not going to let it go without a fight. Time to dig in and see what we can ...

... oh. Oh dear that won't do at all.

A good rule to follow when working with these 30+ year old systems, is to (carefully!) open and inspect before applying any power. In this case I'm very glad I did. Three large filter capacitors on the power supply have very obviously swollen and burst, spreading their corrosive bile all over the neighborhood.

The back side of the power supply circuit board was a wasteland of rotting solder mask, corroded traces, and displaced silkscreen. The electrolyte has eaten its way down the leads, through the solder, and left carnage in its wake all across the bottom of the board.

First order of business is getting those old capacitors removed from the board so cleanup can begin. If you've never worked with hardware of this vintage, a fair warning — make sure you're working in a well-ventilated area. Sure the solder has lead and the flux ain't great for the lungs, but the big concern here is the unholy stench of heated capacitor electrolyte hitting the nostrils like the revenge of Poseidon's refuse bin. The local fish market has nothing on these things.

The old solder, especially when mixed with the electrolyte, tends to behave in a very un-solder-like fashion. It will refuse to melt and when it does it will slump around like wet sand rather than flow like liquid metal should. While it may seem counter-intuitive, the best way to get rid of it is to add more fresh solder to it. On these single-sided boards with large components like this, a spring-action solder pump works well for getting the old parts removed, and then some solder braid will clean up the pads well.

Once the old parts are out, I like to thoroughly clean the area with isopropyl alcohol to remove the electrolyte and years of grease and dirt and pet hair that may have cemented itself to the board. In this case I also needed to use a mild abrasive to remove that damaged solder mask where it had bubbled up off the corroding copper traces. I was lucky here that none of the traces were actually broken or corroded through completely. Clear nail polish works well for protecting the now bare copper (just make sure it's not the UV-cure gel stuff).

From here I turned my attention to the case, because the power supply is the last item removed and first installed when conducting a complete tear down of this printer, and it didn't make sense to put my newly cleaned power supply into a dirty old case.

I'm not really a fan of retrobrite, and these large case pieces would be a real challenge anyway. So all I want is to clean up the dirt and rust and as many scuff marks as I can. As far as I'm concerned, the rest is just part of the history of the item. Each mark tells a story of how this item was used, not just put up on a shelf to be looked at. And if I didn't have any interest in using the machine until it completely falls to pieces, I wouldn't be bothering with going fishing replacing old capacitors.

This is a good point to do some testing. There may still be more wrong with that power supply. Output voltages could have drifted out of spec from other components aging, or maybe I installed capacitors that don't quite match the originals. The ImageWriter II/L power supply has three outputs — +5VDC, -5VDC, & +26VDC. With no load on the power supply, I measured the outputs at around ±7V and 30V. That seems high, but it's not outside of what I would expect for a power supply that's not actually driving anything. This would be a good point to use an adjustable test load, but since I don't have one of those, I'll just have to move forward with my "well it seems fine'

Spoiler: it was not fine.

As part of its startup sequence, the ImageWriter exercises all of its stepper motors to get everything to a known state. This high current draw immediately after power on was more than its old power supply could give. There's clearly more than bad capacitors on the supply, but identifying what exactly is still beyond my current skill level.

So in the interest of getting the machine working (because I have plans for it), I opted to try replacing the power supply with something more modern. The catch here is the odd assortment of voltages the original supply provided. It's easy to find a ±5VDC supply, but 26V is virtually unheard-of.

Apple's documentation for the printer mentions the +26V supply is for driving the motors. I suspected that the 26V supply was less carefully regulated and probably targeting something more like 24V. Sure enough, the stepper with the highest voltage rating on its label was 24V. With a little extra current capacity available, I figured the printer would function just fine with a 24V supply.

The catch is, 24V & ±5V is not a common configuration. There are plenty of 12V & ±5V supplies, but that won't do here. I settled on a Mean Well 24V & 5V supply with a -5V inverter ... And promptly ordered the wrong part. I had a nice new 12V & 5V supply. That's ok, once I got it in hand it was a bit too large to fit in the space I had anyway.

So I got a different Mean Well 24V supply and a separate 24V-5V DC-DC converter. It's a bit of a mess all crammed into the bottom of the case, but it should give all the right voltages (or near enough).

I did have to remove the power switch from the old supply though. That particular part has long since been discontinued, and compatible replacements proved difficult to find.

Now that it's all assembled, it's time to test. This is the part that always makes me nervous, especially when dealing with mains voltages. There's so much that can go so very horribly wrong.

I started out with a smoke test — switching on power briefly to make sure there were no direct shorts that might cause an explosive failure. No smoke is a good sign, so check the voltages. With no load, the new supply rails read 23.99V, 5.00V, and -5.55V. That's about as good as I could ever ask for. So now there's only one thing left to test … does it actually print?

Success!

It's not perfect. Every once in a while it will stutter while printing and get stuck with the carriage on one side or the other. It really needs a complete disassembly, thorough cleaning, and relubrication. That kind of mechanical teardown is a bit beyond what I'm comfortable with at the moment, but I'll happily settle for mostly working over not working at all.

#vintage computing #macintosh #imagewriter #imagewriter ii/l #computer repair #apple #apple computers #dot matrix printer #mean well #it's always the power supply #power supply

[magicclam]

Progress on the Heathkit amplifier project!

This sequence shows the progress of the power supply unit I'm building to power both Heathkit amplifiers. Since the inside of the power supply is just plywood, I used a dark gel stain to unify the wood and make it look a little nicer. Then put on a few coats of satin poly.

Next I added the internals. There's a power transformer which supplies 5 volts for the rectifier tube as well as B+ voltage for the plates, then there's a secondary filament transformer which provides 12.3 volts for the tubes in each amplifier.

Pictures 5 and 6 show the decorative cedar enclosure which will fit over the power supply. I'm particularly pleased with how the power light looks when lit!

Last picture shows one of the amplifiers plugged into the side of the PSU. The other amp will plug in on the other side.

I have a little issue right now where my B+ voltage is low under full load. It's supposed to be 390V, but I'm getting more like 360V. Right now debating whether to swap out the power transformer or just run it on lower voltage than the schematic calls for.

Will keep you posted, stay tuned!

#electronics #soldering #woodworking #vintage #antique #amplifier #Heathkit #power supply #fun

[raxcl]

Robot girls having a severe malfunction

#robot #android #oc #robots #robot oc #robotgirl #androidgirl #power supply #robot girl #mecha

[commodorez]

A variety of blown-out Data General Nova and Digital Computer Controls power supplies, courtesy of Forgotten Machines.

Vintage Computer Festival Midwest 17

#vcfmw17 #vcf midwest 17 #vintage computer festival midwest 17 #commodorez goes to vcfmw17 #data general #digital computer controls #nova #power supply

[koreanaswego]

Korean Word of the Day

전원

Power supply

#korea #korean #learning korean #korean word of the day #power #power supply

[panfore28]

This is the vorgin video about our products shows， we feel pleased to be one of the members in big tumblr community

#power supply #usb charger #battery charger #adapter

[rhinolux-hiisign]

How to Choose the Best Power Supply in Mumbai?

You might have the best signage for advertising your brand and its products, but it won’t work without the appropriate power supply. Without the necessary power supply, it becomes difficult to ensure fruitful execution of advertising ability. Thus, you need to ensure that you get hold of the best power supply in Mumbai.

However, choosing the best power supply becomes a difficult decision at times, with numerous options available. Here, you must go for the top power supply companies in India. Consequently, one must look at a few parameters to adjudicate their characteristics before arriving at a final thought.

Tips to Choose the Best Option

Certain tips will help you make the right decision;

Form Factor

The power supplies come in different sizes according to the customer's needs. Most of the standard builders opt for standard-ATX power supply. A small form factor PSU might be helpful if you are looking for a smaller system. Thus, ensure that you thoroughly examine the product specifications before finalizing the purchase.

Figuring Out The Right Wattage

The power supply requirements differ from one LED module to another. Here, you need to figure out the right wattage for your LED module for signage. Once you have that figured out, choose the power supply unit offering the appropriate power supply.

Higher Power Doesn’t Mean Higher Quality

Many people get deceived by the notion that higher power generation would resemble a higher quality. Some power supply units might sport a 500W but might not offer the same continued power supply for longer. Numerous companies try to build up a brand image by sporting a greater power supply than actual. This deceives the probable customers. In addition, such companies claim to offer higher wattages at lower prices to attract customers. Eventually, the customers realize they made the wrong decision.

Here, it becomes necessary to choose the top power supply companies in India to ensure you get the best quality products at a trusted price.

Consider the Expert Reviews

When it comes to selecting the right power supply unit for your advertising billboards or backlit boxes, do not rely on sparkling advertisements. Here, you have to consider the experts' reviews and opinions to ensure that you get your hands on the right product. The source for such expert review depends on the tests and examinations a PSU goes through. The tougher the examination process, the better the chances for an authentic result. The power supply units surviving the quality checks and associated tests emerge to be the most trusted ones. Here, the industry experts keep a constant tab on the products to rank them every year. Consider looking at the expert reviews on your preferred product's website before making the final decision.

Modularity Parameters

Modularity forms an integral part of your power supply as it determines whether you have control over the wires attached to the unit. There are different types of modular power supplies to facilitate the right choice. Let us take a glance at them;

-       Fully Modular Power Supply: None of the wires come pre-connected in a fully modular power supply. You helm the connection responsibility, thus assuring complete control.

-       Semi-Modular Power Supply: Semi-modular power supplies try to ease your worries by coming with a few pre-connected wires. These are the most important ones, including motherboard power. The remaining cables are up to you to connect.

-       Non-Modular Power Supply: This type of power supply takes away all the burden of connecting the cables. All the cables come pre-connected, whether your LED backlit screens need them or not. The non-modular power supply will come in handy for people requiring connections to multiple billboards or power requirements. If one buys it to meet a singular requirement, the remaining wires will be wasted.

Check the Efficiency Rating

You must always try to purchase the power supply units that sport a higher efficiency rating. A higher efficiency rating would symbolize a higher power output throughout a longer duration without fail. In addition, the electricity consumption would not be high, thus saving you enough money. The efficiency rating depends on how well your power supply transforms alternating current into direct current. The 80 Plus certification is the most common parameter here.

Necessary Certifications

Your power supply unit must have the necessary certifications to ensure its authenticity and efficiency. When the PSU has all the required certifications, you can trust it for some heavy-duty power supply. However, you must be careful about fraud certifications.

Final Thoughts

Always trust Top Power Supply Companies in India like HiiSign, who dedicate their expertise to crafting the best products. With assured power supply support, your advertisement will rise to the ranks of efficiency. 

#singage #branding #power supply #advertising #hiisign #power supply companies

[thedeepssystem]

SAP (Systems, Applications, and Products) is an enterprise resource planning (ERP) software that is widely used in many industries, including engineering construction and operation. Here are some of the SAP functional areas that are relevant to this industry:

Project System

Plant Maintenance

Procurement and Inventory Management

Production Planning

Sales and Distribution

Finance and Controlling

These are just some of the SAP functional areas that are relevant to the engineering construction and operation industry. There may be other modules that are specific to certain industries or business processes.

#SAP Consulting #SAP Communication #Power Supply #Health care

[supertrader123]

Led modules and power supply

Super Traders is a trading company in Delhi NCR. It is a retail store for different outdoor and indoor advertising products like banners, roll up stands, sun boards, display boards, wall graphics and many more. Top brands like Innox, Innotex, Printex, Adverr are some of the partner of Super Traders. It is one of the best trading company in Delhi NCR with high quality products and affordable prices. For exploring more you can visit: 91-783860006

#supertraders #led modules #power supply #super traders india #signage industry #trading company

[fuzzkaizer]

pedal extensions for adding a power supply jack

called "case riser"

cred: facebook.com/Andy Backover, Fendy Yusof

#extension #power supply #hacks #case riser #3d printing #enclosure extension

[powerfar]

Powerfar smart home energy storage products adopt an integrated design, exquisite and beautiful, and easy to install. It can supply power for residences, public facilities, small factories, etc. The energy storage system is similar to a micro power station, which can solve the pressure of urban power supply.

During non-peak hours, the energy storage products charge themselves for use during peak or power outages. In addition to emergency power supply, the smart home energy storage system can save money and balance your electrical load.

#home energy storage #power supply #energy storage

[neververy4]

[ Warning; high piched noises ]

HEY! I don’t think this Power Supply is alright

#neververy4 #Computer #power supply #Pentium 3

[magicclam]

A while ago, I challenged myself to do a 1-day restoration of one of my radios. Start-to-finish. 

I chose a Radiola 18 that I’d gotten back in summer. Started with the power supply section (as usual). It may look gross with the tar everywhere, but it’s electrically sound. 

I replaced the few capacitors that needed replacing, and eventually added a fuse as well. The capacitors were all located in a square can on top of the chassis, but rather than dig out all the tar and old caps that were in there, I just disconnected them and mounted new ones underneath. 

Finding room under the low chassis was a bit of a challenge, but worked out just fine.

Initially I thought the power switch was bad, but it turned out to be ok, so I reattached it later.

Next step is the RF/Audio section, so stay tuned for that!

#Radiola #radio #antique #restoration #electronics #soldering #vacuum tubes #fun #power supply

[lightning-storm-studies]

No-stress summer learning challenge 🌞: day 43

03.08.2023

It's been quite a long time since the last update, but I haven't abandoned this challenge, I'm learning as planned. I just didn't have time to make an update. I've finished the design of an unstabilised power supply (which is a part of this course). The second photo shows a PIR motion sensor, that will be used for a cat fountain, so that the pump only starts running, when one of my cats walks nearby.

📖 Janusz A. Zajdel - Limes Inferior

🎧 thea wang - garden song (i prefer a loon)

#no-stress summer learning challenge #no-sslc #lightningstormstudies #electrical engineer #engineering student #engineering #engineer #electrical engineering #engblr #engineering studyblr #electrical engineering student #electricity #electronics #motion sensor #pir sensor #power supply #rectifier #rectifier bridge #circuits #summer learning #summer studying challenge #summer holiday #summer vacation #healthy learning #motivation #productivity #studyblr #studying #inspiration #summer