Your getting some great advice on this:
What I would say is that a dedicated isolation transformer is a specialised part designed and built to exacting safety standards and it is designed to be used as it stands.
Anything else you add to it on the basis that 'this or that' might improve some aspect is pure folly and is pretty much guaranteed to compromise the safety aspect, perhaps catastrophically.
What I would say is that a dedicated isolation transformer is a specialised part designed and built to exacting safety standards and it is designed to be used as it stands.
Anything else you add to it on the basis that 'this or that' might improve some aspect is pure folly and is pretty much guaranteed to compromise the safety aspect, perhaps catastrophically.
lol I bet you don't spend $100s (or $1000s) on a speaker wire either. Based on your stated experience, are manufactrers stated life of electrolytics at 15 or 20 years just them covering their behinds?
I have a Kenwood KR-7400 and a KR-6160. What you'd do to either of those would be my greatest interest.
I think now it's a matter of mounting the unit in a corded steel enclosure, adding a fuse, switch or two, couple indicator lights and a GFCI outlet.
(and fixing my static barrier damage.)
I would troubleshoot the unit IF....IF it had an issue....using my bench testing equipment and the training and experience that I got by taking up professional serving of consumer home entertainment products.
I didn't get my NESDA Certification "diploma" that's hanging on my wall above my workbench for a wall decoration.
In my teens I learned how to read and understand schematic diagrams, the resistor color codes, and Ohms Laws.
That was for starters.
Once I had that memorized, it was on to bigger things...
Some people would argue it's cheaper (if you're paying the labour) to replace the parts rather than test them. You have to pay to remove the parts and reinstall them either way so why not use a new one with better specs for ~20% more cost? 😀
Of course, if you have the skills, time, and equipment than why not? After all it is DIY.
Of course, if you have the skills, time, and equipment than why not? After all it is DIY.
In my field, troubleshooting doesn't always require removing things to test them.
Of course, DIY'ers usually don't have the same training or equipment.
ICT assembly line test equipment does just this, if you have a lot of familiarity with a particular circuit design and the right test equipment it is possible to test in circuit without removing parts. In some cases a component failure is pretty obvious (shorted capacitor) in other cases less so. The ICT is relatively infallible, but doesn't always always start that way. Having something to directly compare against makes it much easier. Ever wonder what golden boards are for?
I do a combination of both, only removing a part if I suspect it is bad and then testing it. (I don't always get it right either, usually misidentifying what turns out to be a good part.)
I suspect in a lot of cases service techs who see a lot of gear and become very familiar with it don't need to remove parts normally as part of the diagnostic process.
There are some component testers on the market that are intended for in circuit testing, and work well. You can find these on Amazon and eBay. I have never needed one since I designed most of what I fix and I can usually tell without much digging.
I do a combination of both, only removing a part if I suspect it is bad and then testing it. (I don't always get it right either, usually misidentifying what turns out to be a good part.)
I suspect in a lot of cases service techs who see a lot of gear and become very familiar with it don't need to remove parts normally as part of the diagnostic process.
There are some component testers on the market that are intended for in circuit testing, and work well. You can find these on Amazon and eBay. I have never needed one since I designed most of what I fix and I can usually tell without much digging.
When I first used braid, I thought it was pretty amazing, but then I got one of these!
It's bloody fantastic!
https://www.amazon.ca/HighTop-Automatic-Desoldering-Electric-Soldering/dp/B0932TJX9X/ref=sr_1_5?keywords=desoldering+tool&qid=1649722317&sprefix=desol,aps,72&sr=8-5
It's bloody fantastic!
https://www.amazon.ca/HighTop-Automatic-Desoldering-Electric-Soldering/dp/B0932TJX9X/ref=sr_1_5?keywords=desoldering+tool&qid=1649722317&sprefix=desol,aps,72&sr=8-5
Yes indeed, they are one handy device!
I have one of those old squeeze-bulb desoldering tools, also works great for those big blobs of solder off the boards.
But the braid works fine on small tight spaces.
I had one of the ones with the bulb. It was garbage compared to this. It uses a solenoid to suck much faster than I can release any bulb while holding it in the right place 🙂 Just don't let go of the button until you aim it at the garbage/floor/glass of water you're using or you'll blow melted solder all over the board lol
What's the best way to mount this in a steel box? (I assume a bolt though the hole.)
Specs say it has an Epoxy potted center w/1/4″ hole but it has a 1/2" hole. (the rubber
spacer has a 1/4" hole) (post 12 on page 2 has a picture)
Using a 1/4" bolt with a spacer to fill out to 1/2"? Then a 1/4 nut could be braised to the inside of the box.
Using a 1/2" bolt with a nut braised to the outside of the box?
Figured I better ask in case I'm missing something again. 🙂
Specs say it has an Epoxy potted center w/1/4″ hole but it has a 1/2" hole. (the rubber
spacer has a 1/4" hole) (post 12 on page 2 has a picture)
Using a 1/4" bolt with a spacer to fill out to 1/2"? Then a 1/4 nut could be braised to the inside of the box.
Using a 1/2" bolt with a nut braised to the outside of the box?
Figured I better ask in case I'm missing something again. 🙂
Best to bolt through the box. It sounds like a half inch bolt would be the best option here. Make sure that the top cover or anything else cannot contact the top of that bolt - in a metal box this would constitute one heck of a shorted turn. (very bad actually)
Thanks kevinkr
Your statement that anything contacting the top of that bolt, including the cover, has me
wondering if I'm missing something again. Isn't the case top and bottom, along with the bolt
itself, attached to mains ground?
Your statement that anything contacting the top of that bolt, including the cover, has me
wondering if I'm missing something again. Isn't the case top and bottom, along with the bolt
itself, attached to mains ground?
Actually nothing to do with grounding, since the bolt passes through the center if both ends contact the box this will create a shorted turn. It's equivalent to a very large piece of wire wrapped around the core and connected together. Using a magnetic field the transformer induces voltage in the wire wrapped around the core, the center bolt and the box are conductive and look like a single shorted turn, hence the problem.
Sparks would fly!
But in all seriousness, a toroid should be mounted with rubber disk on each side, 1/4 inch bolt/nut/washer or plate attached ONLY by the bottom panel of a metal box.
Just have to make sure the bolt doesn't stick up far enough to touch the lid.
How much current can one turn make? If you ever looked at those old common Weller solder guns, the 100/140 watt ones. They are a one turn secondary. The mains 120v is fed to a large winding, then the two pipes that stick out to stick a tip into are actually two ends of the same pipe. It is bent into a U shape, with one side running through the coil. That is a transformer, and it steps the 120vAC down to really low voltage but high current. High enough to heat the wire tip to solder-melting temperatures.
How much current can one turn make? If you ever looked at those old common Weller solder guns, the 100/140 watt ones. They are a one turn secondary. The mains 120v is fed to a large winding, then the two pipes that stick out to stick a tip into are actually two ends of the same pipe. It is bent into a U shape, with one side running through the coil. That is a transformer, and it steps the 120vAC down to really low voltage but high current. High enough to heat the wire tip to solder-melting temperatures.