help - timecode running creates hum w/xlr mic at DVinfo.net

Jim Burer · March 23rd, 2004, 06:22 AM

was wondering if anyone could give me a clue as to what is causing (and how i can solve) this problem:

using the ma-100 on a canon xl-1. attaching a at835b eng mic to it. when i press record, i get a hum/interference/noise the cycles with the timecode????? (definitely records it.)

i've tried using a different mic - a friend's sennheiser eng shotgun mic, a different xlr cable. same result. i've also tried setting the audio 1 input to both "mic" and "mic att 20". same result.

the two things i haven't tried are switching out the ma-100, which i will as soon as i can find one to try it out on, and running it into audio 2, which i'm not sure you can do. at least i wasn't succesful getting it to be recognized in the menu when i ran the rca cables from the ma-100 over to the audio 2 inputs.

does anyone know what's going on? will a new ma-100 fix it?

any help would be greatly appreciated. i know you guys/gals know your stuff.

thanks in advacne. --jim

Don Palomaki · March 23rd, 2004, 04:49 PM

How loud is the noise (i.e., dB relative to max digital record level)

The battery or power source you use may effect noise. May be cause by internal construction of the batttery and the routing of the power leads. Try using a different make/model battery, see if the noise level changes.

Also, be careful how you route the MA-100 leads. Do not allow any other leads to run between the MA-100's power and audio leads.

You can connect the MA-100 to the Audio2 input, but you have to be recording in 12-bit, 4-channel (St1-St2) mode to record from the Audio2 input.

Richard Alvarez · March 23rd, 2004, 04:54 PM

Search for my post regarding a high pitched hum that came from the 16x manual lens. If you are using this lens, it MIGHT be a problem. It was for us on the Xl1, but not on an Xl1s

Jim Burer · March 24th, 2004, 06:51 AM

thanks guys for the advice. i switched the ma-100 rca cables to go into the audio 2 inputs and the noise disappeared. my assumtion would then be that something is causing interference with either the ma-100 or the audio one inputs.

i'm still going to try and find another ma-100 to try, but my question is now, what could that something be that's causing the interference and is it something i should send into canon for diagnosis and repair? anybody have experience with them enough to know if they are good at solving these types of problems.

by the way the cycling noise does not register on the audio level monitor on the canon xl1 but is definitely there when i try and capture audio and listen via headphones. i have also tried 3 different battery packs and also a bescor battery belt. still present.

thanks again for the help.

jim

March 23rd, 2004, 06:22 AM	#1
Jim Burer Tourist Join Date: Mar 2004 Location: chattanooga, tennessee Posts: 2	help - timecode running creates hum w/xlr mic was wondering if anyone could give me a clue as to what is causing (and how i can solve) this problem: using the ma-100 on a canon xl-1. attaching a at835b eng mic to it. when i press record, i get a hum/interference/noise the cycles with the timecode????? (definitely records it.) i've tried using a different mic - a friend's sennheiser eng shotgun mic, a different xlr cable. same result. i've also tried setting the audio 1 input to both "mic" and "mic att 20". same result. the two things i haven't tried are switching out the ma-100, which i will as soon as i can find one to try it out on, and running it into audio 2, which i'm not sure you can do. at least i wasn't succesful getting it to be recognized in the menu when i ran the rca cables from the ma-100 over to the audio 2 inputs. does anyone know what's going on? will a new ma-100 fix it? any help would be greatly appreciated. i know you guys/gals know your stuff. thanks in advacne. --jim

March 23rd, 2004, 04:49 PM	#2
Don Palomaki Wrangler Join Date: Sep 2001 Location: Northern VA Posts: 4,487	How loud is the noise (i.e., dB relative to max digital record level) The battery or power source you use may effect noise. May be cause by internal construction of the batttery and the routing of the power leads. Try using a different make/model battery, see if the noise level changes. Also, be careful how you route the MA-100 leads. Do not allow any other leads to run between the MA-100's power and audio leads. You can connect the MA-100 to the Audio2 input, but you have to be recording in 12-bit, 4-channel (St1-St2) mode to record from the Audio2 input. __________________ dpalomaki@dspalomaki.com

March 23rd, 2004, 04:54 PM	#3
Richard Alvarez Inner Circle Join Date: Sep 2002 Location: San Mateo, CA Posts: 3,840	Search for my post regarding a high pitched hum that came from the 16x manual lens. If you are using this lens, it MIGHT be a problem. It was for us on the Xl1, but not on an Xl1s

March 24th, 2004, 06:51 AM	#4
Jim Burer Tourist Join Date: Mar 2004 Location: chattanooga, tennessee Posts: 2	thanks guys for the advice. i switched the ma-100 rca cables to go into the audio 2 inputs and the noise disappeared. my assumtion would then be that something is causing interference with either the ma-100 or the audio one inputs. i'm still going to try and find another ma-100 to try, but my question is now, what could that something be that's causing the interference and is it something i should send into canon for diagnosis and repair? anybody have experience with them enough to know if they are good at solving these types of problems. by the way the cycling noise does not register on the audio level monitor on the canon xl1 but is definitely there when i try and capture audio and listen via headphones. i have also tried 3 different battery packs and also a bescor battery belt. still present. thanks again for the help. jim