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SAFETY VIDEO | All About Fuses | Changing the Fuse in Your Amp
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- เผยแพร่เมื่อ 16 ส.ค. 2024
- WATCH THIS VIDEO before touching that fuse holder!! ALWAYS unplug your amp before any type of service. MOST IMPORTANTLY - I film these videos to document my repairs and inform viewers of basic safety tips. Your tech is always the most qualified person to perform any service/maintenance to your amp.
Let me know how the new audio setup sounds on your end! The first upload was missing one channel, so hopefully this upload sounds better.
Remember to Like and Subscribe :)
PATREON: www.patreon.com/fazioelectric
INSTAGRAM: fazioelectric
"Caution! Disconnect power supply before changing fuse. " Says so right on the amp. Conveniently, near the fuse. Thanks for the discussion of the 2 approaches to switch wiring. !
that was the most polite way to say, "Don't be a window-licker and unplug your amp every time....", that I've ever seen.
Ah hahahahahahaha! A "window licker" ! The image is hilarious and says it all. You made me laugh at 6am...
🤣😂 Yup! I just punched after doing 20 in the service. Window-lickers and crayon-eaters abound in this world…
You are exactly correct. The hot should go to the fuse first, and then the switch. I know many people believe it should be the other way around. The reason is if you have the switch first and it happens to be turned off, then unknowingly switching it live while changing the fuse could really spoil your day. Also if your switch happens to fail short, you will learn how to fly like superman. If you know that fuse socket is live, then you are more likely to be taking care .... or even better, disconnect the power
that's absolutely correct, bro
This. All of this!
Thank you for man-splaining everything she just said in the video
@@joehoughton-gisby8218 "Man-splaining". What a great word! I love it. I am surprised my wife hasn't come up with that. I confess it goes with the territory of being an Electrical Engineer for 40 years. Thanks for making me smile.
ROTFLMFAO at "Could Spoil Your Day!!!" I think it would be a well deserved consequence if they have zero common sense!!!
I agree with Coleen. Circuit protection (fuses and or breakers) should always be first in the electrical stream. Switches can fail short and if they are unfused, expect sparks and flames...
If there's a phase to chassis fault between the switch and fuse, you can turn it back on on a hard short circuit. Same reason you don't put a single fuse in the neutral return. RCB's should catch this ***SHOULD***, but why depend your equipment and possibly your life on it.
You are correct, Colleen. As an electrician, over-protection (fuse) comes first. That is the case in all levels of electric... To protect everything on the load side of the line. And yes, the sound is much improved. Thank you and good luck.
"...that would not feel very good." Getting shocked SUCKS! I appreciate that you cover so many basics. I'm not "formally" educated in electronics and this is all very good for me. Congrats on the growth of your channel!
Getting shocked only sucks if it's DC. If it's AC it BLOWS, usually only you across the room if you're lucky...
I like how you resoldered the right side lead on my headphones jack, thanks
LOL
That was a lot of fun to watch. Reminded me of my first electronics lesson back when I was 12 yo. The teacher, as we entered the room, asked us if we liked to laugh and we said yes. Having a electrician grandfather, I had fallen into that same trap many times but I kept my mouth shut and hoped it was something else. It wasn't, He gave us a 220v shock, at a very low current and short duration just to make us aware of what it means to play games with electricity.
Later on, in uni, every time I saw my flatmate, an electrical engineering student (I was in mechanical engineering) doing repairs on a live wire and I used to ask him... do you like to laugh? He didn't understood at first but luckily eventually he learned to shutdown the power before starting to work.
Audio quality is A++++
I am relieved to hear that! Thanks :)
Colleen, I've been meaning to write to you for a while. I love watching your videos so much; I hope you make many more. I think that anyone that repairs things for a living is living a noble existence, esp.in our nightmarishly disposable society. I love your chill vibe. You have singlehandedly inspired me to start learning electronic basics as I've wanted to for many years. There seems to be a high ratio of comments to views on your channel. I hope you don't have to endure too many people of a certain gender eager to prove they know more than you. Keep up the great work and thanks again.
Totally concur. Great compliment and ‘perspective’ Dave.
I was taught to use the one hand behind my back rule when *very carefully* testing voltages points in old tube televisions or radios, so in case you should bump something with your hand, you do not want it to travel through your heart and out through your other hand that might be in contact with a ground.
Wiring the fuse first is absolutely correct! Just make sure to take the live to the “pull out” end of the fuse. This way the amp will be dead when you pull the fuse, regardless if the amp is plugged in or not.
Thanks so much I have had amps for years and never been educated in such a cool way
Glad you posted this new video, Colleen. I'm glad you go to great lengths to emphasize safety. One thing I would like to add is that people get confused about voltage and amperage. A lot of people don't realize that it only takes one quarter of an ampere, .25, to kill a human being. People have had voltage in the five or even six figures go through them and have survived. But it's not something I would bet mine or anyone else's life on. Electrical burns, for example, are the worst that can happen to a person, because they burn from the inside out as electricity tries to go to ground. So you keep right on stressing electrical safety! And thanks once again, I have learned so much from you, and I look forward to every new video!
Love the improved audio! Nice to see your channel growing so quickly.
For the Air Force this is Tech Order 33-1-32 input wiring checks. We are all proficient. Power cords, fuses, fuse holders, power switches, correct wiring, and proper temporary substitutions if needed.
As someone who has a lot of experience with electrical and electronic equipment, I can say without any doubt that you are right about the fuse being before everything else. Anyone saying otherwise is talking out their ass. Honestly, the fuse should be as early in the circuit as possibly as anything prior to the fuse isn't protected.
People like this haven't seen what happens when things go wrong. I've seen what happens when a car drives into a pole carrying 11kv with normal house voltage underneath, and a whole street suddenly has 11kv wiring. I've seen what happens when lightning gets into a network.
In these cases fuses aren't much help, but still, modern conventions like this exist for a reason, these amps predate safety, and as another great TH-camr always says, safety regulations are written in blood. And yes this is a regulatory requirement. Not only best practice but it's the law.
You are a good teacher and a pleasure to watch.
Yay! The audio is so much better. Very pleasant to listen to now. :D
It was ALWAYS pleasant to listen to..
1) Dark hair + blue eyes + multimeter = beautiful amp tech
2) In case of touching a live wire the US 120V is better than the italian 230V! (I speak by experience...)
3) Keep up doing videos, love'em!
If the fues blows this is a sign that there is a heavy load or short circuit pulling current...so we use a lamp limiter to test this out...just remove the large tubes and power the amp up...if the lamp stays bright power off straight away.
If skilled in electronics servicing then track the fault..all good tips to this ever growing field.
Well done Colleen !!!!! You are spot on
Absolutely correct. Fuse before switch and for good reason. All these classic amplifier schematics showing that and people think they know better? You and your channel are great.
Hi from Dublin -- also always check the correct fuse is in an amp when you get it -- and a bit part of safety is the hot goes to the fuse tip not the collar -- also please use the correct size blade for uk style holders -- and lastly some amp brands have fuses with can only be accessed internally -- keep up the great vids !
Great video as always! The reason that the fuse should be first in the circuit is mostly because that way it protects as much of the amp as possible. Ideally it should not even be in the amp, but in the plug as British plugs are designed, as that way it also protects the line cord, but line cords are usually short enough that any reasonable conductor cross-section can withstand the full fault current long enough for the breaker to pop in the panel.
Wow ! US plugs don't have fuses ? I'm more than a bit horrified by that, both by the fact itself and that I didn't know it.
@@jimfarrell4635 US residential power distribution is normally radial, with a separate breaker (typically overcurrent only in older properties) for each circuit, of a suitable value to protect the cable. The UK system uses a ring final circuit protected by a 32A fuse or breaker, with individual appliances protected by a fuse in the line cord plug of (hopefully) appropriate rating, typically 3A.
Good advice, not just for the techs, but for the players who occasionally have to stick their fingers into high voltage areas. Thank you!
If you don't already know about Apex in the San Fernando valley, you should go and scrounge for electronics. They specialize in vintage electronics, alot of aircraft parts, old timey switches, transformers, tubes, resitors etc. Even some NOS stuff if you dig deep enough. Pretty amazing place. They pretty much have everything you need, to build or repair vintage amps with period correct vintage parts. Great channel btw.
It's sad, but you do actually have to tell people to unplug their amplifier before they work on it. I thought about it when you said that, and then I realized that you were right by telling everyone. Wow.
Such a relaxing voice. The good looks don't hurt either, but love your explanations and teachings.
Keep'em coming!
I used to work as a telecom technician, and every day I would solder jumpers on the main distribution frame of the exchange. There was on some circuits an ancient technology called 1+1 or 0+2 which multiplexed two phone lines over 1 physical pair, and these always had 110 volts rather than the usual 48 to 52 volts of a phone line. This was not fun when you were reaching your hot and sweaty bare arm through the frame between distribution blocks covered in 100s of sharp solder tags and suddenly you would get lit up and inadvertently jerk your arm across the tags. My hands and arms were always covered in little cuts.
From Barcelona Spain ♥️ i an woman guitarrist tankyou sou much ,☀️☀️☀️
I have always hated the discussion of "fuse before switch?". In a lot of cases people will say Switch before fuse, so the fuse isn't hot if it needs to be changed. This is absolutely true, in only ONE case. If the device is hardwired to power! If the device has a plug, it should be fuse before switch. That way if the switch fails, the fuse can protect the chassis as well as anyone who comes into contact with it.
You service and repair many many many more amps than I ever will, so I will take YOUR advice and not some random comment in the comments section. Keep up the videos they are awesome, cheers from Australia.
Fuse before switch! Yes! For the reasons you mentioned. And for those who think that if you put the fuse AFTER the switch there won't be any voltage on the fuse if the switch is off, you've got a painful and nasty lesson awaiting you! Because the fuse is still connected through the power transformer to the other side of the AC mains! Yes, it's the neutral, assuming everything is wired correctly, but that's never something you should assume. UNPLUG!
Just an amazing channel full of the best information available.
Great point about always unplugging. I still prefer switch, then fuse. I guess I am with Uncle Doug on that one.
I used to be a test engineer at McDonnell. I ran 110 through myself on a few occasions. Gets your attention!
Audio is brilliant !! , fuse always before the switch , if the switch fails there is nothing to protect or stop full current to the switch , yes they do blow up . That’s regulation over here and we are 240v …
Great Channel and great content !!!
Finally, someone could tell me what I needed to know.
Seriously awesome videos! For some reason you make it incredibly simple to understand. Your a great teacher and you point the camera in the right place! A+
Congrats on 20k plus subs. High quality content and presentation will do that. Well done!
Thanks, Colleen! The lav mic is working wonders
The new audio sounds perfect. Thanks for the safety tips! G'day from Melbourne, Australia.
Straya
Dont argue with colleen! She is a professional. and,,,,,,,,,I love her. There i said it.
Thanks for the better audio! I am still a firm believer in wiring the hot side to the switch first then the fuse holder. It's just common sense and safer...
Good video. Here's a tip for you amp techs out there: On many amps, the discharge path for the power supply reservoir capacitors will be broken if the fuse blows. Marshalls definitely. If the HT fuse is blown in a Marshall, assume that the filter caps are charged to full operating voltage. Unplug the amp and replace the fuse with a good one. That will discharge those capacitors. But never trust, CHECK the caps with your meter before sticking your fingers in there.
Fuse first. Always, fuse first! Great vids btw!
Here in Canada, the electrical code states that the line conductor MUST connect to the fuse first. No ambiguity about that.
As an unapologetic Marshall fanboy...I'd love to see a vid on that Marshall you used in this video. That is if you're actually working on it. Regardless, love the channel and keep up the good work!
She's great isn't she !! ... she's another me would you believe .. both into this sort of thing .. pity we are so far apart as we could both work together and even pass as sisters lol 😆!
thanks again I appreciate your teaching style
Great reminder to unplug before fuse swaps. My Marshall made Vox AC30tbx has one of those awful flathead fuse holder. They're fine for the back of a head, but in the bottom of the back of a combo it's a pain in the ass. Mine is basically stripped from years of use. Maybe I should change to another one like your Champ here.
Thoroughly enjoy your videos but on a different note: Your hair looks glorious!
Also important: not only should the fuse be connected directly to the hot side of the line cord (black in the US, blue in Europe), but the line cord should be connected to the rear of the fuse holder. It's correct in the amp on the bench that you showed. When connected this way, the fuse will lose contact with the line cord as soon as it moves a fraction of an inch out of the socket.
I really appreciate your focus on safety. I got a 300 volt DC shock hand to hand when I was 18 (long story, not a guitar amp). I'm now 70. I still remember how much it hurt and how long the blisters on my hands took to heal.. Fortunately it was current-limited or I wouldn't have made it to 19.
Enjoyed this video and the audio improvement as well. Sound quality is much better.thanks.
Please make more videos? Love your channel!
Bless you for sharing your wisdom with us!!!
Timing of this video wow! I just blew a fuse on my 76 champ on power up. Might have to take to a tech now
Great to hear the improved sound quality! Your videos are amazing, all the hard work you put into it is paying off!! 🎸😎👍
When you actually study the design and intended use case of those fuses holders they are relatively safe of course providing the hot is connected to the proper terminal and the user isn't doing anything more than you demonstrated here. There are certainly different types of fuse holders that would be impossible not to get shocked pulling the fuse out and that's why you don't see them manufactured into amps from the factory. I mean many people might think that those are the same and therefore interchangeable with the type of holder you might see under the dash of your car or connected to your car stereo but they are not. While they will technically hold the same size fuses not all fuse holders are designed or rated to be interchangeable or a matter of preference. Audio sounds nice. Great explanation and points. Your right, above all it is better to be safe than sorry. :)
Nice video, Colleen. Good tips. Another one I tell people all the time is never "check" a fuse by looking at it. Always use a VOM to make sure it's got continuity. Sometimes you get lucky and a fuse is "visibly blown". But I've had a lot of fuses that "looked good", but weren't continuous. And of course, never, ever "fix" a blowing fuse with a larger rating.
Ty...... as someone who lives a laugh, it’s like in the IT world, did you turn it off an on again? That’s amp repair 101. Glad you shared this. I guess lots of folks like to take chances while things are plugged in.
Right! Some amp builders are not considering a short across the switch to ground if it was wired in first. I love Uncle Doug but he's just wrong on this point.
Thanks so much for the education. I am happy I found your channel
Hi Colleen!... I'm bamboozled!!.. I bought an old crate hybrid 80 watts,lights up,speaker works,but no connection to guitar.Guitat Center gave me amp for 50 bucks.I do lots of transactions with good ol "guitar center's,anyway the 3 preamp tubes don't light up either.This crate I cleaned up and is in excellent condition!!!!...;hell,I'd be happy with solid state only at this point.This crate got excellent reviews from highly reputable names..... I'ma make crate legends😂😊!!... With some technical support?!!
It's also worth noting that in the Fender amp, the end of the fuse holder gets the live. The other end goes to the circuit. So you'd have to stick a screwdriver or something inside to get a shock from it, which is part of the point of those styles of fuse holders.
Hello Coleen.
I am enjoying your videos and think you do a great job.
I worked as an repair tech back in the '70's in Western New York initially working on tube amps and then on audiophile amplifiers. In the early 80's, I began
repairing computers and installing early networks (something that at the time, paid a lot more money). I have continued to work on amps - mostly on the side.
When I saw the White amp video, I was immediately struck by the fact that you were wiring the fuse socket ahead of the switch which is the correct thing to do. Of course, this entire issue has become a subject for debate - not just on your channel.
But I'd like to present another side of the debate for your consideration. First, I agree that the end user should always disconnect the power cord from the wall socket before doing anything inside their amp, including changing a fuse. However the reality is that end users don't always know or take proper precautions. This is an unfortunate, but a fact nonetheless. I can't remember how many times I've taken in an amp for service and found in a grossly improper fuse or tube installed, or found a wall plug with the ground pin snapped off. Why do they put 'DO NOT EAT' warning labels on Ice packs and packets of silica gel? Apple even placing a label on the iPod shuffle warning users not to eat it.
People just do dumb things.
There is an issue you may encounter when adding a 3-wire cord to some old equipment. It stems from the fact that some old amplifiers may use the chassis for signal ground. In these cases, connecting the power cable ground wire to the chassis can cause a ground loop and it's annoying hum. I've have encountered this only once with an old guitar amplifier - one that was made in Japan. But I think it's more common with older PA and Hi-Fi amps. This is just something to store away in case, after adding a three wire power cord, you find some sort of new hum.
As one of your subscribers, I thank you for reviving this debate and for your videos in general and good luck with the channel.
Yes you are absolutely rite ,esp in your said of what happens in reality . Some units not just guitar amps but other equipment have the fuse on the outside and even on the front clearly accessible .This is very deceptive as many people would go on to considering something on the front and or on outside as safe or give a false sense to consider drastic safety measures be taken when fuse removal , where it is even in reach of a baby's/child etc touch . Turning it by the off /on switch will do nil on that issue of making fuse removal safe esp if the fuse is wired incorrectly ! . There should be a warning sign or label clearly indicating the power cord must be isolated ie unplugged from power esp at the front prior to any fuse removal even as a reminder to techs .And there really is no need for any fuse to be on the front . if they have labels like -- do not eat -- as you indicated they should have signs warning with that too like --- unplug cord before removing fuse .--regardless of whether before or after the unit's power switch . It would be obvious to do that if working inside the unit but not all fuses are inside the unit and then there's DURING situations one could forget in the process . One in that situation would have the later wiring .Still its nice to see a young person let alone a lady so dedicated and knowledgeable in the electronics field esp guitar amps kudos to her .
Another helpful video, appreciated again! This one is important for guitar players who often change their own fuses, I can't believe how many vintage amps have the wrong fuses!
You have a great teaching style and the content is great. Thanks, I hope to see more.
Watching you I don't even mind the tech stuff.
All good info. Thanks for the safety tips.
Your channel is super interesting, Colleen.
I stand right with you on the fuse position .. it MUST be the first port of call for the active ( hot) wire .... especially here in Australia where we use real energy at 245VAC !! I notice that schematic diagram you used shows the fuse located on the opposite leg of the primary winding .. big no no !!
I agree that the fuse should be wired directly to the hot line cord wire. Also, that wire should go to the end terminal of the fuse
holder not the terminal close to the fuse holder opening. That way if the line cord is plugged in then the line voltage will be way at the bottom of the fuse holder not right next to the open end when the fuse holder cap is removed.
Making sure your amp isn't energized before working on it is a good idea. Especially if you aren't looking to have a perm in every hair on your body. 😁
0:48 This is the essential thing. Professional electricians ALWAYS make visible gap in the circuit (in high, medium and low voltage circuits) -- the rule is: switch off voltage, disconnect circuit from mains (in power grids disconnector is a special device to make this visible gap, in low voltage systems at home it is a plug outside socket or "fuses in the pocket" rule) and ground it. Very nice movies, I like old stuff like this:)
I've got an adjustable wrench with a semi-melted side that reminds me to discharge my capacitors!
I have a multi tool that reminds me the same
That sounds like a line from a a sci-fi movie.
@@ghostburgers4284 Starring Bruce Willis and Milla Jovovich 😆 👍
This is the most informative, educational and inspiring channel that I have found:)
I have been learning something in every educational video!!!
Excellent short video. Think you may be the first to cover this ‘simple’ (aka ignorable) subject. Brilliant too that the channel is growing - keep on keeping on!
Thanks for the video!
3:34 I think you meant to say "will blow the fast blow fuse immediately" You gestured the fast blow with your hand, but stated slow blow.
So after fixing the amp we want to see you jam out with the amp!
Love the video content on your channel. I appreciate the sharing of knowledge.
You make playing electric ⚡️ guitar 🎸 feel dangerous …like playing with 🔥🔥🔥 yeah 😎🤘🤘🤘
I literally don't care about amps yet I keep watching your videos! you must be doing something extraordinarily well. Those 20k subscribers are well deserved.
If dealing with anything plugged in the golden rule is ask Mehdi Sadaghdar to do it for you. If he isn’t available unplug it, no matter how quick a job it is you can guarantee electricity moves faster.
Just because someone is young it doesn’t mean they lack knowledge. Of course they’re still learning, but aren’t we all? Young people can soak up knowledge better than those of us with grey cells and they remember what they’ve learnt too. I’d take a young person with real passion over an old person just doing the job as a 9.00 to 5.00 any day. Having said that the most knowledgeable person I’ve ever met around electrical components was a 95 year old woman who ran the electrical shop in Jedburgh in Scotland. She’d run the shop since WWII and I met her in 2015.
Helpfull... hope there is more to follow.
Oh... maybe there are some tool types that you believe do the job more safely and efficiently than others. Like chop sticks lol or irons, strippers, voltage meters. Any helpful tips on using equipment would be appreciated too. Dont stop
Great job! Thanks for you and all others sharing this great art! I am learning from a tech with 60 years of design and experience and it is a fun hobby! I appreciate the safety reminder and learned why some of the wires are so thick and others thin in the fuse.
Also wire the tip of the fuse to hot. So if they do reach in on the blown fuse they’ll be safe.
Amazing videos, always a pleasure.
Colleen , New to your channel...Enjoy your style and format ....Safety is always very important....Audio sound very good ...Take care..
The fuse should be the first thing in the curcuit I think, the chance of shorting out is theoretically higher if there's more wiring and a switch inbetween, however the chance is very low. So, in my book, it doesn't really matter...
fun fact: @1:40 in reality it's more than 121V one gets when shocked.
the notation we use refers to RMS outlet AC, so the peak voltage potential is 120V x √2 =170V, 340V peak to peak. :}
Great video and Channel!
Always with great content!
I learn every time I watch this Channel!
Thank you Colleen!
Good upgrade on the audio!
Nice and very informative and clear information...Learn something all the time. Thanks for the tips, and sharing..Ed..U.K..😀
Cool video. I accidentally touched the B+ on a DRRI recently with one hand only. That did NOT feel good. Lucky I’m not an 👼🏼 by now!
I love fuses.
Salsa 'El Pato'....the best!
I love Uncle Doug's videos but you have a new sub - thank you
Love watching your videos
Am learning a lot
May Your Tribe Increase
Longshot, but if you get access to one I’d love to see you review (maybe open) the new reissue Champs. I’m sure they’re PCB, but I’d like to know if it looks well made with quality parts.