Hi,
I have an old Luxman R-1040 receiver. It works perfectly and has great sound, but it emits a strange humming sound.
As soon as I power it up, it hums. The sound doesn't come from the speakers, it come from the receiver itself. It's loud enough that I can hear it about a feet away, but not loud enough to interfere with music.
This sound stays the same with or without components attached to the receiver, and it doen't vary with volume or any combination of switches. It stops as soon as I power it off, but with a little pop in the woofers.
It's been doing this since I had it last year.
Is it normal, or is my good old receiver slowly dying?
Thanks!
I have an old Luxman R-1040 receiver. It works perfectly and has great sound, but it emits a strange humming sound.
As soon as I power it up, it hums. The sound doesn't come from the speakers, it come from the receiver itself. It's loud enough that I can hear it about a feet away, but not loud enough to interfere with music.
This sound stays the same with or without components attached to the receiver, and it doen't vary with volume or any combination of switches. It stops as soon as I power it off, but with a little pop in the woofers.
It's been doing this since I had it last year.
Is it normal, or is my good old receiver slowly dying?
Thanks!
I have no knowledge of this particular reciever, but I'd bet that the noise is probably coming from the mains (power) transformer. But there are other possibilities.
Sometimes, after opening, the sound source is obvious. Other times it's not.
There are a couple of methods that I've used to trace noise sources:
1) Keep one hand behind your back.
Push suspect parts with an insulated screwdriver, and see if it changes. Be careful not to short circuit anything.
2) Remove all jewelery!
Borrow a very dry wooden spoon from the kitchen. Place one end against (not in) your ear, and probe with the other end.
There has been some mention in other threads recently, that there is some residual DC component on the mains supply in some parts of your continent recently. That'll make it hum. Even a
Sometimes, after opening, the sound source is obvious. Other times it's not.
There are a couple of methods that I've used to trace noise sources:
1) Keep one hand behind your back.
Push suspect parts with an insulated screwdriver, and see if it changes. Be careful not to short circuit anything.
2) Remove all jewelery!
Borrow a very dry wooden spoon from the kitchen. Place one end against (not in) your ear, and probe with the other end.
There has been some mention in other threads recently, that there is some residual DC component on the mains supply in some parts of your continent recently. That'll make it hum. Even a
Hi Toshito,
"I can hear it about a feet away"
This is, regrettably, quite normal with some pieces of equipment. I have a CD player that I used to hear at night from accross my room. I quietened it by AC coupling its mains feed - a DC offset can cause the power transformer to hum. A suitable schematic was posted here:
http://www.diyaudio.com/forums/show...403&perpage=15&highlight=fat cap&pagenumber=2
Please note that while this method works fine for smaller gear (say, <50W power consumption), I am not sure if it is suitable for a larger appliance, like your receiver. If you try it, make sure you include the diodes which are for the protection of the cap!
See ya,
Tim.
PS - I am not sure from your post wether the hum has developed only recently, or wether it has always been present. If it is a recent development, there may be a fault.
"I can hear it about a feet away"
This is, regrettably, quite normal with some pieces of equipment. I have a CD player that I used to hear at night from accross my room. I quietened it by AC coupling its mains feed - a DC offset can cause the power transformer to hum. A suitable schematic was posted here:
http://www.diyaudio.com/forums/show...403&perpage=15&highlight=fat cap&pagenumber=2
Please note that while this method works fine for smaller gear (say, <50W power consumption), I am not sure if it is suitable for a larger appliance, like your receiver. If you try it, make sure you include the diodes which are for the protection of the cap!
See ya,
Tim.
PS - I am not sure from your post wether the hum has developed only recently, or wether it has always been present. If it is a recent development, there may be a fault.
Speaking of reviving an old thread.
I have a R-1040 on the bench with exactly the same problem. It's definitely the mains transformer.
I measured between 0.077mV and 2.67mV DC over a period of 10 minutes.
As this can't be the problem I suspect time did the job on the transformer.
Oh..in case someone has the schematic lying around, I would be very thankful.
/Hugo
I have a R-1040 on the bench with exactly the same problem. It's definitely the mains transformer.
I measured between 0.077mV and 2.67mV DC over a period of 10 minutes.
As this can't be the problem I suspect time did the job on the transformer.
Oh..in case someone has the schematic lying around, I would be very thankful.
/Hugo
Hi Hugo,
Didn't see this thread until now.
Try to tighten the bolts holding the laminations together, then the transformer back to the chassis.
I'm assuming nothing is getting warm, like caps or rectifiers. It's a nice heavy set. Looks pretty when it's clean and sounds good too.
-Chris
Didn't see this thread until now.
Try to tighten the bolts holding the laminations together, then the transformer back to the chassis.
I'm assuming nothing is getting warm, like caps or rectifiers. It's a nice heavy set. Looks pretty when it's clean and sounds good too.
-Chris
I 'did' the bolts, to no avail.
Switching the voltage selector to 240V helps a tiny bit.
Customer doesn’t care about the transformer noise, he’s more then happy I fixed the tuner.
The receiver is in mint condition, not one trace of dirt, looks like he never played.
/Hugo
Switching the voltage selector to 240V helps a tiny bit.
Customer doesn’t care about the transformer noise, he’s more then happy I fixed the tuner.
The receiver is in mint condition, not one trace of dirt, looks like he never played.
/Hugo
Hi Hugo,
Darn, it wasn't that easy! 😉
I'd be interested to find out why the transformer is so loud. I haven't run across one doing that. Many Counterpoint's, but not classic Luxman. LV regulator for the tuner fault?
-Chris
Darn, it wasn't that easy! 😉
I'd be interested to find out why the transformer is so loud. I haven't run across one doing that. Many Counterpoint's, but not classic Luxman. LV regulator for the tuner fault?
-Chris
What's an LV reg.?
The blue variable cap on top of the CV was loose.
I guess we talk about the same part.
/Hugo
The blue variable cap on top of the CV was loose.
I guess we talk about the same part.
/Hugo
Hi Hugo,
LOL
I apologize for that!
LV reg = low voltage regulator.
So, what are you calling a CV ?
-Chris
LOL
I apologize for that!
LV reg = low voltage regulator.
So, what are you calling a CV ?
-Chris
Got you where I wanted. 😉
CV: Condensateur Variable.
On top there is a small cap, I guess a few pF, to adjust the frequency with the scale needle (88-108). Forgive the bad jargon; I’m sure you know what I mean.
/Hugo
CV: Condensateur Variable.
On top there is a small cap, I guess a few pF, to adjust the frequency with the scale needle (88-108). Forgive the bad jargon; I’m sure you know what I mean.
/Hugo
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