Household electrical problem

[Swerd]

Good morning Swerd, any update? Again, I would check the ac main fuse first before paying the repair shop, assuming there was never any smoke, flame, pops high heat etc., observed.

There was nothing unusual, like smoke, flame, or pops. Just an amp that couldn't be switched on.

The AC main fuse (12A slow blow, 250 VAC) is ceramic not glass, so I couldn't see anything broken inside, like a filament. I didn't have another fuse the right size, 30 mm long, and didn't know where to find one locally, so I decided to take it to the shop. In the past, I've usually seen fuses blow when there is also an underlying problem.

When I took it to the shop last Friday, the guy said he'd get back to me in 5 days. He's closed Sunday & Monday. So 5 days would be Thursday. I'll call him later today to see if he's had a chance to look at it yet. I'm still hoping it needs a new switch or power supply caps. I saw those online photos of the four large caps in the B&K EX4420. I wonder what they now cost?

I'm still watching that Quad 909 on fleabay, and wondering if it will sell before I hear about my amp.

 

[Irvrobinson]

Those look like Cornell Dubilier caps. If so, they're probably still good.

 

[PENG]

There was nothing unusual, like smoke, flame, or pops. Just an amp that couldn't be switched on.

The AC main fuse (12A slow blow, 250 VAC) is ceramic not glass, so I couldn't see anything broken inside, like a filament. I didn't have another fuse the right size, 30 mm long, and didn't know where to find one locally, so I decided to take it to the shop. In the past, I've usually seen fuses blow when there is also an underlying problem.

When I took it to the shop last Friday, the guy said he'd get back to me in 5 days. He's closed Sunday & Monday. So 5 days would be Thursday. I'll call him later today to see if he's had a chance to look at it yet. I'm still hoping it needs a new switch or power supply caps. I saw those online photos of the four large caps in the B&K EX4420. I wonder what they now cost?

I'm still watching that Quad 909 on fleabay, and wondering if it will sell before I hear about my amp.

If there is no inrush current limiting device/circuitry, transformer primary fuse (120v side) can blow simply after many switching cycles because the inrush current can be 20 times or much higher for .1 second or longer depending on a number of factors.

If those big caps are around 15,000 uf, 75 to 80v and of high quality types, they probably cost $40 to $70 each, just an educated guess, without googling..

 

[Swerd]

If there is no inrush current limiting device/circuitry, transformer primary fuse (120v side) can blow simply after many switching cycles because the inrush current can be 20 times or much higher for .1 second or longer depending on a number of factors.

If those big caps are around 15,000 uf, 75 to 80v and of high quality types, they probably cost $40 to $70 each, just an educated guess, without googling..

So it's possible that all I have is a blown AC main fuse. I guess it's too late to worry about being foolish about that.

Dumb question: The fuse looked like the one below (30 mm long). But it had a red stripe at one end and a black stripe at the other. Does that mean the fuse is polarized? I found 6×30 mm 12A slow blow 250 VAC ceramic fuses online, but I never saw one with those red & black stripes.

 

[PENG]

So it's possible that all I have is a blown AC main fuse. I guess it's too late to worry about being foolish about that.

Dumb question: The fuse looked like the one below (30 mm long). But it had a red stripe at one end and a black stripe at the other. Does that mean the fuse is polarized? I found 6×30 mm 12A slow blow 250 VAC ceramic fuses online, but I never saw one with those red & black stripes.

Me neither, maybe it isn't just a fuse. For example, there is a thing called diode fuse, but the picture does show the typical look of a small ceramic fuse (look can be deceiving). Fuse should have no polarity.

If every time you turned on the amp (cold start) the light dimmed, and sometimes dimmed a lot, then most likely the amp does not have inrush current control. If it dimmed just a little, then it most likely has some sort of control and in that case that 12A slow blow fuse should almost never blow unless there is a fault.

 

[KEW]

I see the Quad got bought off of Ebay yesterday.
Was that you?
Any word from repair shop?

 

[Swerd]

I see the Quad got bought off of Ebay yesterday.
Was that you?
Any word from repair shop?

No it wasn't me. As TLS Guy predicted, it sold at the asking price.

I called the repair shop on Friday, but he hadn't gotten to my amp yet. I was busy on Saturday and didn't think of calling until after he closed. He's closed Sunday and Monday. So I'll call tomorrow.

So far, I've been driving all 5 speakers with the AVR, without problem or noticing anything different.

 

[Swerd]

I picked up my repaired amp today. The shop owner replaced defective bridge rectifier diodes in the power supply section. All the other circuits checked out OK. He attached some speakers and tested it in the shop for me. It cost $145, a lot less than $1000 to replace the amp.

He replaced the power supply fuse, and put a spare in the space in the fuse holder. It only cost him pennies, but it's a nice touch. He also said his work is warranted for 30 days.

The shop owner also said, "It was a pleasure opening that amp up and working on it – they don't make them like that any more." I responded that if it was such a pleasure, maybe he should pay me. He laughed but didn't respond directly. Then he muttered something in Spanish having to do with 'those Chinese', but I didn't understand it.

This owner operated repair shop gets a plug:

Electronics Service Center http://www.esc-website.net/
12216 Parklawn Drive, Suite 112
Rockville, Maryland 20852
301-881-8637​

So that ends the thread I originally titled as "Household Electrical Problem". It was the amp and not the AC power outlets as I had first thought. But compared to replacing this amp, the repair job seems like a bargain.

Thanks for all the responses.

 

[highfigh]

The shop owner also said, "It was a pleasure opening that up and working on it – they don't make them like that any more." I responded that if it was such a pleasure, maybe he should pay me. He laughed but didn't respond directly. Then he muttered something in Spanish having to do with 'those Chinese', but I didn't understand it.

Did it sound like "Los payasos!"?

 

[Swerd]

Did it sound like "Los payasos!"?

No, if I heard him right, it was more like this

Esos ladrones! Resaltarán tus huesos limpiar.​

 

[highfigh]

No, if I heard him right, it was more like this

Esos ladrones! Resaltarán tus huesos limpiar.​

I take it he's not a fan since that translates to "Those thieves! They will wash your bones clean.".

 

[Swerd]

They will wash your bones clean.".

I think it sounds better in English as "They'll strip your bones clean."

 

[highfigh]

I think it sounds better in English as "They'll strip your bones clean."

Actually, the Spanish-English translator I tried used 'highlighted' for 'limpiar', which usually means 'cleaned'. It's on restroom signs all over, telling people to wash their hands before leaving.

 

[Alex2507]

It cost $145, a lot less than $1000 to replace the amp.

If we were on a 'How To Save' forum ...

... but you heard TLS, stop using that B&K!

 

[Swerd]

If we were on a 'How To Save' forum ...

Hey, I thought this is a 'How To Save' forum.

... but you heard TLS, stop using that B&K!

I admit, there was a small voice inside my head telling me to ignore any doubts about spending $1K and jump on that Quad amp. But I decided to be patient and wait for the repair guy.

TLS may word his opinions strongly; he is not always correct; but he is far from always wrong. Many of us have benefited by following his advice. When I needed an external phono pre-amp, I simply ordered what he recommended and never regretted it. (That was easy as it didn't cost much.) If I wanted to spend money on phonographs or pick up cartridges, I'd skip all the shopping around and just do what he says. If I needed a new amplifier and didn't own any, I'd look for what he suggests. But I cannot, or will not, spend lots of money while ignoring a life-time of frugality.

Yesterday, I did open up my amp just to look inside. I didn't take a pictures because it looks exactly like the on-line photo posted above. The only difference I could see were the speaker binding posts. Mine has the red & black type, not the gold plated type in the photo.

On a different subject, tonight, I'm going to the local concert hall. The BSO is doing one of those previously unscheduled concerts that happen each summer – Bach's Brandenburg Concertos. I guess the musicians know it well enough to perform it without much rehearsal or direction. I've always had a recording of that, so I'm very familiar with the music. Some people think Bach is boring, but seeing it performed live is a lot of fun because really good musicians seem to have fun as they play. I hope that's the case tonight.

 

[Alex2507]

Amp lust is a thing. I've got a B&K 2140 in service at my Jerry Garcia look-a-like friend's place. The thing works great for the 180 bucks I spent on it. Sometimes you get lucky.

Of course I'm glad you got your amp back in working order. Now I'm wondering how long before it makes its way back into your system. Are we going to have to call Dan?

 

[slipperybidness]

Hey, I thought this is a 'How To Save' forum.
I admit, there was a small voice inside my head telling me to ignore any doubts about spending $1K and jump on that Quad amp. But I decided to be patient and wait for the repair guy.

TLS may word his opinions strongly; he is not always correct; but he is far from always wrong. Many of us have benefited by following his advice. When I needed an external phono pre-amp, I simply ordered what he recommended and never regretted it. (That was easy as it didn't cost much.) If I wanted to spend money on phonographs or pick up cartridges, I'd skip all the shopping around and just do what he says. If I needed a new amplifier and didn't own any, I'd look for what he suggests. But I cannot, or will not, spend lots of money while ignoring a life-time of frugality.

Yesterday, I did open up my amp just to look inside. I didn't take a pictures because it looks exactly like the on-line photo posted above. The only difference I could see were the speaker binding posts. Mine has the red & black type, not the gold plated type in the photo.

On a different subject, tonight, I'm going to the local concert hall. The BSO is doing one of those previously unscheduled concerts that happen each summer – Bach's Brandenburg Concertos. I guess the musicians know it well enough to perform it without much rehearsal or direction. I've always had a recording of that, so I'm very familiar with the music. Some people think Bach is boring, but seeing it performed live is a lot of fun because really good musicians seem to have fun as they play. I hope that's the case tonight.

Just curious, discrete diodes in the rectifier? Or rectifier diode package?

Either way, good news that the fix was relatively simple and cheap.

 

[Swerd]

Amp lust is a thing. I've got a B&K 2140 in service at my Jerry Garcia look-a-like friend's place. The thing works great for the 180 bucks I spent on it. Sometimes you get lucky.

Yes, amp lust is a good way to describe it . While my most rational voice was saying "wait for the repair shop to fix your amp", other less rational voices were saying "Go buy that Quad amp NOW!", or "You know that Quad is only 140 wpc. What you really want is 225 wpc!"

While my amp was in the shop, I used my AVR to drive all 5 speakers. B&K claimed 150 wpc, but I always wondered if the AVR's amp section was no different than the many 125 wpc amps they made. I didn't try to put it to any test, but the AVR sounded fine to me.

Of course I'm glad you got your amp back in working order. Now I'm wondering how long before it makes its way back into your system. Are we going to have to call Dan?

I just put it back in earlier this morning. A brief test (a CD and some FM radio) indicated all is well again. I had 3 cups of coffee this morning (some really good Ethiopian). I had to wait until most of that had passed thru me before I would commit to lying on the floor for a while struggling with wires.

Dan helped me rewire the BR player to the (non-HDMI) AVR with 6 RCA cables. When I originally installed the BR player, I had two 6' long component video cables lying around. So I used them, but they were just barely long enough. With use and some routine shifting around, the rear channel connections came out. I bought two sets of 10' long component video cables to use instead, but I just didn't bother putting them in for years because of the unsettling bad experience I had with Bonnie as my other pair of hands. Dan & I made quick work of it. (Note to self: Always have at least 3' extra length on cables.)

I did notice how ugly and green the old speaker wires look . Replacing them will be the next big thing – one of these days. Maybe I'll spend some time on the net searching for an audiophile who claims that nasty green speaker wires sound better than those with shiny copper.

 

[Swerd]

Just curious, discrete diodes in the rectifier? Or rectifier diode package?

The guy in the shop showed me two discrete rectifiers that he had cut off a board. Each had a black spot visible on them. He described two other diodes (in the same circuit?), but all this quickly got above my head. So I wasn't sure if he also replaced them.

I did ask him about the power supply capacitors, but he said they were fine and he didn't expect they would fail anytime soon.

 

[slipperybidness]

The guy in the shop showed me two discrete rectifiers that he had cut off a board. Each had a black spot visible on them. He described two other diodes (in the same circuit?), but all this quickly got above my head. So I wasn't sure if he also replaced them.

I did ask him about the power supply capacitors, but he said they were fine and he didn't expect they would fail anytime soon.

Rectifier should have a total of 4 diodes. If it were me, if I'm changing 2 diodes then I'm gonna go ahead and change the other 2 as well.