Right; the simplest likely explanation (without actually looking at
the circuit) is that the Sony PiP circuit has a higher value resistor
in series with the output than other recorders use.
-matt
On Aug 21, 2009, at 21:42, Klas Strandberg wrote:
> Great Matt! Thank you!
>
> This needs some consideration.
>
> You have to load the Sony 3 times as much to squeeze the 0,5 mA out
> of it because the voltage drops..?
> Do you see any other interpretation?
>
> Klas.
>
>
>
> At 18:22 2009-08-21, you wrote:
>> On Aug 21, 2009, at 7:07, Klas Strandberg wrote:
>>
>>> Hi folks!
>>>
>>> It would help me and users if I better knew about the plug in power
>>> voltage that different recorders provide.
>>>
>>> This is the test:
>>>
>>> 1/ Connect a potentiometer and a mA meter in series between input
>>> and ground.
>>> 2/ Set the potentiometer so that the mA meter shows 0,5 mA.
>>> 3/ Measure the voltage between input and ground.
>>>
>>> For the moment I am specially interested in the voltage that Sony
>>> PCM-D50 provides at a given current, like 0,5 mA.
>>>
>>> Klas.
>>>
>>>
>>>
>>
>>
>> OK, I just did the LS-10, too: 1.93V
>>
>> To summarize (view in a monospace font):
>>
>> MODEL V (unloaded) V @ 0.50 mA Load (Ohms)
>> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D
>> Sony D10 2.82 0.52 1030
>> Zoom H4n 2.84 1.82 3606
>> Olympus LS10 3.02 1.93 3828
>>
>>
>> So the Sony is an outlier here.
>>
>> Note that my 0.50 mA current adjustment was only approximate -- I set
>> the load resistor to get as close to 0.500 mA to flow as I could, but
>> really got only within +/- 1 % or so. So the loaded voltage isn't
>> exactly R * .0005, because the current wasn't exactly 0.5000 mA.
>> It's
>> just close. Ohm's law still applies in Philadelphia, in spite of
>> what
>> the numbers above might suggest!
>>
>> V measurements were done with a recently calibrated Fluke 189.
>> Current was measured with a Fluke 289, also recently calibrated.
>>
>> -matt
>>
>>
>> mab blogs at http://www.crypto.com/blog/
>>
>>
>> ------------------------------------
>>
>> "While a picture is worth a thousand words, a
>> sound is worth a thousand pictures." R. Murray Schafer via Bernie
>> Krause
>> Yahoo! Groups Links
>>
>>
>>
> Telinga Microphones, Botarbo,
> S-748 96 Tobo, Sweden.
> Phone & fax int + 295 310 01
> email:
> website: www.telinga.com
>
>
>
>
>
> ------------------------------------
>
> "While a picture is worth a thousand words, a
> sound is worth a thousand pictures." R. Murray Schafer via Bernie
> Krause
> Yahoo! Groups Links
>
>
>
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