Posted: Monday Feb 17th, 2020 07:33 am |
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1st Post |
juwi_uk
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Hi
Noticed this week that my CM9000 based system has developed a noticeable hum; noticable in that it is heard through the wall in my sons room next door to the closet where it is installed! ☹ï¸
Any ideas guys. Is the transformer known to start humming after a few years etc?
Julian
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Posted: Monday Feb 17th, 2020 07:36 am |
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slychiu
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It is not known to hum after a few years, but anytng can become faulty. Or it may be resonant with some other low freq devceHow old s it?are you sure it is due to the transformer. Did you try turniong off the mains and let it run on battery to se if the hum is still there?
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Posted: Monday Feb 17th, 2020 07:42 am |
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juwi_uk
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Yeah I tuned off the mains and the hum went so to me that points at the transformer. Are these still available to purchase?
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Posted: Monday Feb 17th, 2020 07:56 am |
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slychiu
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Please Check if Laser have any. These are heavy and expesive to ship overseasYou may be able to find a similar transfor in Farnell 15 to 16VDC output 2.5A (40VA)
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Posted: Monday Feb 17th, 2020 07:57 am |
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Swiss-Toni
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Im sure that you can get the transformers from Laser.com, ps have you got any other powered devices on that electrical circuit when you powered it down
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Posted: Monday Feb 17th, 2020 08:08 am |
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Swiss-Toni
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slychiu wrote: Please Check if Laser have any. These are heavy and expesive to ship overseasYou may be able to find a similar transfor in Farnell 15 to 16VDC output 2.5A (40VA)
Im sure I have questioned that size transformer before as it is 230V~14V 1.8amps as I was looking at potentialy using that size one you have refered too!
Last edited on Monday Feb 17th, 2020 08:09 am by Swiss-Toni
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Posted: Thursday Feb 20th, 2020 07:03 am |
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TheMax74
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Hello Juwi,
i've swapped my transformer with a new one from Laser some years ago.
Mine was not humming, but i started to have warnings for low battery.
I suggest you to buy 1 or 2 of them as spare parts (i bought 3 of them, because i have 2 SEM as well), because your CM9000 will last for decades, and have spare parts is a good idea, until you find it.
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Posted: Monday Feb 24th, 2020 08:30 pm |
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Posted: Monday Feb 24th, 2020 08:38 pm |
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TheMax74
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Do you need one of mine?
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Posted: Tuesday Feb 25th, 2020 12:11 pm |
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slychiu
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If you want to buy one, we still have some available, but the shipping would cost more. Send an email if you need
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Posted: Friday Feb 28th, 2020 03:04 pm |
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Ghyllwood
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I have done lots of tests with different transformers over the years. I've tried toroidal and conventional and found 15v was the most optimum. Anything over 16v causes the heat sink on the regulator to get quiet warm and below 14.2 is not enough to regulate the output voltage to 13.8vdc.
Interestingly, if you cant find an original Comfort transformer, try A Fermax 4800 1.5 amp rated at 12vac, but actually give out 15.5VacLast edited on Friday Feb 28th, 2020 03:18 pm by Ghyllwood
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