Posted by Smarty on 10/07/05 18:06

Glad to assist. I need to know 3 things before designing an attenuator pad.

1). Where is the Line Output coming from, a balanced or unbalanced source?
Balanced sources will have an XLR connector typically whereas unbalanced
sources typically use an RCA phono jack.

2).What type of camcorder are you using? It is normally safe to assume a
consumer camera has -10dBV input but I would prefer to know for sure since
some require a different signal level,

3). Although this is a somewhat minor detail, some camcorders provide DC
power through their MIC-IN jack to support electret or other microphones
requiring a pre-amp / power. I normally would add a little blocking
capacitor in the pad to keep this DC from showing up back at the other end
of the cable at the LineOut device's output stage. If the LineOut device
uses an output transformer, for example, or does not provide a buffered
output, this DV voltage can add an offset/bias which you want to prevent.

Let me know and I will calculate the resistances and give you a design.

Smarty



"Richard Crowley" <richard.7.crowley@intel.com> wrote in message
news:di69dd$ftn$1@news01.intel.com...
> "Rick Merrill" wrote ...
>> Andy & Kim wrote:
>>> Thanks for the advise guy's. Smarty could you give me some values of the
>>> resistors I would need for a T-pad attenuator, just as a guide.
>
>> I second the request!
>
> http://www.uneeda-audio.com/pads/
>

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