Need help locating replacement part (blue component)

Delta prime

Joined Nov 15, 2019
337
Hi there. :) what you have there is a metal oxide varistor, or MOV, protects sensitive electronic equipment from voltage spikes in the power line. A gadget may have thousands of transistors, resistors and other components, but only one or two varistors. While it may look similar to a capacitor, you can identify the device by its color, markings and location. The MOV will always be close to the equipment’s power supply and wired to a fuse. Many MOVs have a bright, solid color and are usually coin-sized.
In series with the fuse and in parallel with the power supply, you’ll find one or two MOVs. They will be either block or disc-shaped like a capacitor. Unlike a capacitor, which has capacitance and voltage ratings printed on it, the MOV will have a simple code or voltage. Like a capacitor, the MOV has two leads. Many disc MOVs are black, bright blue, red or yellow so they stand out. Smaller varistors may be oblong blobs on a pair of axial leads.
 

Thread Starter

Ossimo81

Joined Jun 5, 2020
11
Hi there. :) what you have there is a metal oxide varistor, or MOV, protects sensitive electronic equipment from voltage spikes in the power line. A gadget may have thousands of transistors, resistors and other components, but only one or two varistors. While it may look similar to a capacitor, you can identify the device by its color, markings and location. The MOV will always be close to the equipment’s power supply and wired to a fuse. Many MOVs have a bright, solid color and are usually coin-sized.
In series with the fuse and in parallel with the power supply, you’ll find one or two MOVs. They will be either block or disc-shaped like a capacitor. Unlike a capacitor, which has capacitance and voltage ratings printed on it, the MOV will have a simple code or voltage. Like a capacitor, the MOV has two leads. Many disc MOVs are black, bright blue, red or yellow so they stand out. Smaller varistors may be oblong blobs on a pair of axial leads.
Hi, thank you for the quick reply, it's on a speaker crossover, I have searched the numbers on Google but not getting any results to find a replacement. Can you help me identify what the markings mean on it? Thanks in advance.
 

dendad

Joined Feb 20, 2016
3,535
Can you show the bottom of the board so a circuit can be figured out?
In fact, if you can, that would be a good project for you, to trace the circuit and show us.

Although that does look like an MOV, I wonder if it may be a 750mA Polyswitch resettable fuse? But they are usually yellow, not blue.
MOVs are often blue that that one.
Does it measure open or shorted?
And why do you think it is faulty?
 

Thread Starter

Ossimo81

Joined Jun 5, 2020
11
Hi, thank you for the quick reply, it's on a speaker crossover, I have searched the numbers on Google but not getting any results to find a replacement. Can you help me identify what the markings mean on it? Thanks in advance.
Can you show the bottom of the board so a circuit can be figured out?
In fact, if you can, that would be a good project for you, to trace the circuit and show us.

Although that does look like an MOV, I wonder if it may be a 750mA Polyswitch resettable fuse? But they are usually yellow, not blue.
MOVs are often blue that that one.
Does it measure open or shorted?
And why do you think it is faulty?
I have an IT background but I'm ne to electronics, the speakers work but they are almost 20 years old. I have already replaced the capacitors on the crossovers with some audio grade dayton ones and I'm listening to music on these speakers right now and they sound fine so I'm guessing all ok so far. Do you think the mov would need replacing being 20 years old and also it has a ceramic resistor, would the resistors last this long also?
 

Thread Starter

Ossimo81

Joined Jun 5, 2020
11
"If it ain't broke, don't fix it" comes to mind.
Things can be half broken so to speak. Already had a new receiver break and from what I have found shitty or old crossover components can cause a backfire and short the amp so I'm just being careful
 

peterdeco

Joined Oct 8, 2019
161
I believe that is a disc capacitor. N075 is the temperature coefficient and 60 is the value (usually in pF) but I'm not sure in this case.
 

MrChips

Joined Oct 2, 2009
21,143
My stereo is over 50 years old and still works fine on original components. I have never heard of a speaker back firing. That's a new one to me.
 

dendad

Joined Feb 20, 2016
3,535
I am still puzzled why you think that part is at fault.
There is no reason to assume they have a use by life of less that 20 years. Unless they get damaged, I would think 20 years is still young.
My Tanoy speakers are over 45 years old an have no problems with their crossovers. I expect them to run many years longer.
Also, a better picture of the board may help to identify the part. Is there a designation for it on the board?
 

Thread Starter

Ossimo81

Joined Jun 5, 2020
11
I am still puzzled why you think that part is at fault.
There is no reason to assume they have a use by life of less that 20 years. Unless they get damaged, I would think 20 years is still young.
My Tanoy speakers are over 45 years old an have no problems with their crossovers. I expect them to run many years longer.
Also, a better picture of the board may help to identify the part. Is there a designation for it on the board?
If you read all the comments you would see I mentioned that I already had one of the dedicated amplifiers in a brand new receiver break. Also I get some occasional distortion and the odd pop noise with the receiver that is now broken and I also get the same thing with a new amplifier I replaced the receiver with. Comparing what I have to what you do is irrelevant and if you cannot answer my question just move on.
 

Thread Starter

Ossimo81

Joined Jun 5, 2020
11
My stereo is over 50 years old and still works fine on original components. I have never heard of a speaker back firing. That's a new one to me.
Well it's all news to me at this stage. If you read your own comment you have not had any issues where as I have so I'm not really talking about you or your speakers am I. I have a limited budget and I don't have the equipment to test these components and they are cheap compared to a new set of speakers and I am trying to determine the issue with process of elimination. Telling me I am wrong based on your own situation is kind of pointless and opinions are like something else.
 

dendad

Joined Feb 20, 2016
3,535
If you read all the comments you would see I mentioned that I already had one of the dedicated amplifiers in a brand new receiver break. Also I get some occasional distortion and the odd pop noise with the receiver that is now broken and I also get the same thing with a new amplifier I replaced the receiver with
I cannot find your comment about that. Unless you are referring to...
Things can be half broken so to speak. Already had a new receiver break and from what I have found shitty or old crossover components can cause a backfire and short the amp so I'm just being careful
Is it in another post?

Comparing what I have to what you do is irrelevant and if you cannot answer my question just move on.
Telling me I am wrong based on your own situation is kind of pointless and opinions are like something else.
Both your replies above are a bit rude.
You came here for help and when we offer opinions based on years of experience all we get back from you is abuse. That is not fair. We are quite happy to help you, there is no need to answer like you have.

In post #13, I have asked you for a good photo. If you can supply some clearly showing the top and the bottom of the board, we can trace the circuit out to help with a better identification of the part.
As it is, there is not a lot more we can do. Your cooperation will go a long way towards answering your question.
Please play nice.
 

Thread Starter

Ossimo81

Joined Jun 5, 2020
11
I cannot find your comment about that. Unless you are referring to...

Is it in another post?



Both your replies above are a bit rude.
You came here for help and when we offer opinions based on years of experience all we get back from you is abuse. That is not fair. We are quite happy to help you, there is no need to answer like you have.

In post #13, I have asked you for a good photo. If you can supply some clearly showing the top and the bottom of the board, we can trace the circuit out to help with a better identification of the part.
As it is, there is not a lot more we can do. Your cooperation will go a long way towards answering your question.
Please play nice.
It's a bit rude just to tell me that I am wrong when all I asked was if someone could identify the component, if you cannot then no need to criticize everything I am doing when a simple no or no comment at all would suffice. It's not really helping me by questioning everything that I am doing when the question is just hey what is this part.
 

Thread Starter

Ossimo81

Joined Jun 5, 2020
11
It's a bit rude just to tell me that I am wrong when all I asked was if someone could identify the component, if you cannot then no need to criticize everything I am doing when a simple no or no comment at all would suffice. It's not really helping me by questioning everything that I am doing when the question is just hey what is this part.
It's a bit rude just to tell me that I am wrong when all I asked was if someone could identify the component, if you cannot then no need to criticize everything I am doing when a simple no or no comment at all would suffice. It's not really helping me by questioning everything that I am doing when the question is just hey what is this part.
I have read a lot of threads the end up like this where some inexperienced person asks for some information and they are basically questioned until they give up rather than given some information or advice...that to me is rude and offensive. Either way there have been some helpful and unassuming comments from some of the people here and I am thankful for those either way. I have finished with this forum and thank you everyone.
 
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