Univolt hummmmm?

GlenCoombe · 09-19-2005, 08:31 AM

I spent the better part of yesterday installing the new stereo / monitor. One of the more vexing problems that I've been avoiding has been a very distinct hum from the univolt. If I trip the gfci breaker that powers the univolt the hum disappears. Am I looking at a replacement? Any ideas as to how to get rid of this as the new stereo would be nice to listen to when I'm docked or when the univolt is in line while the generator is running. Thanks as always for the input...no pun intended.

SafeHarbor · 09-19-2005, 09:08 AM

Hi, Glen,

My Univolt hums, too, but it's keeping a nice steady 13.47 VDC and isn't boiling the batteries, so I'm not too worried about it. The hum is pretty normal.

Do a search for "intellipower" here, and you'll find that lots of other folks are allergic to the hum and lack of multi-stage battery charging of the Univolt. I'll let the other MH guys recommend what to replace it with if you feel so inclined.

Regards,

Lamar

ALANSD · 09-19-2005, 10:05 AM

you mean the stereo picks up a hum from the univolt? If that is the case perhaps a noise supressor would stop it. These are available at Radio Shack and such.
If you mean the normal univolt hum when its running, that is just part of its "charm".

GlenCoombe · 09-19-2005, 03:13 PM

It's actually a very loud electronic hum coming from the stereo produced by the Univolt. Unplug the univolt and everything is fine.... that is if you don't mind that the Sirius head is bad right out of the box.

Now I've got to find another Circuit City on my travels to swap out the unit. But the good news is that the back up camera works!!

Guido · 09-19-2005, 03:56 PM

Two choices.

One is to swap out the univolt.

The other one is to ask the guys at circuit city if they have a noise isolator for the power feed to the stereo. This will filter out the noise and be less expensive than replacing the univolt.

**Janet** · 09-19-2005, 06:18 PM

This issue has been discussed before as several folks had the same problem. You might search for "hum" or look at this thread to read some one else's experience.

68 Overlander · 09-19-2005, 06:28 PM

Glen,
The hum is something you have to live with unless you upgrade to a solid state unit. There are several to choose from. Progressive Dynamics, Iota, WFCO have 3-stage charging and are awesome especially for boondocking or storage. Parallax is a good quality unit availble in single or 2-stage (Timer option)
I agree that 13.47 should not boil your battery. Anything over 13.6 is pushing it and will require more maintenance, especially in the warmer months.

68 Overlander · 09-19-2005, 06:52 PM

Glen,
Are you hearing the hum through your speakers or just from the univolt? If you have noise, humming, or crackling coming from the speakers, I would first check your battery. It needs to be installed and charged to filter the "dirty" DC power.

Bradjun1 · 09-19-2005, 07:21 PM

Glen,
Be careful with your new stereo. I had a hum in my stereo coming from the Univolt and it smoked the unit. My univolt was shot and it was putting over 17 volts of AC into the DC system. I relpaced my univolt with an Intellipower 9100 w/charge wizard and have been very satisfied with the improvement. The charge wizard is a real plus. The install was easy and the weight savings helps too. It is so quiet I keep checking on it to see if it's working. I bought mine from bestconverter.com. Randy at bestconverter was helpful with some install questions.

TwinkytheKid · 09-19-2005, 08:21 PM

Quote:

Originally Posted by GlenCoombe

I spent the better part of yesterday installing the new stereo / monitor. One of the more vexing problems that I've been avoiding has been a very distinct hum from the univolt. If I trip the gfci breaker that powers the univolt the hum disappears. Am I looking at a replacement? Any ideas as to how to get rid of this as the new stereo would be nice to listen to when I'm docked or when the univolt is in line while the generator is running. Thanks as always for the input...no pun intended.

Okay, I saw this on another thread, and it fits this topic, sort of...
Do you know why Univolts hum? They don't know the words! Hee Hee...
Seriously, you chould check all your grounds, for the Univolt, and for the radio. I had a radio in a car that picked up all manner of electrical noise, and it turned out the radio had a bad ground, and was grounding through the antenna.

Janet's Husband · 09-19-2005, 09:46 PM

This thread gives you the answer to your problem.

http://www.airforums.com/forum...861#post154861