What is this component? PRR

[peter purpose]

Gefell MV 692
Marked as 'IS' on the schematic and is the white jobbie in the picture.

ayethengyaw





[ January 31, 2004, 06:57 PM: Message edited by: peter purpose ]

[jrmintz]

Looks like an SIP opamp.

[Bo Hansén]

Hi Peter purpose,

This is a funny one because it can be a own output amp in thich-film circuit (like in Neumann newer designs) but this mike amp can also work if the IS thing is a usal resistor network. (many resistors in same case)

--Bo

[peter purpose]

Thanks guys....the plot thickens.

[gyraf]

I.S.: Integrierte Schaltkreis, German for IC.

Looks very much like an opamp or some other integrated stuff.

Most likely an east-european type.

Jakob E.

[peter purpose]

Thanks Jakob

[buttachunk]

[img]graemlins/beerchug.gif[/img]

[peter purpose]

[img]graemlins/beerchug.gif[/img] yourself chunky

[cjenrick]

resistor array
no power lead, so no silicon
gain setting?

look close and see if you can see the outlines of nine or ten resistors standing up next to each other
on the diode arrays we use, you can make it out easily

[Mark Burnley]

Yea, could be.

I don't quite see how it can't be an active device though? T2, T3 and T4 are all connected with deriving the polarisation voltage for the capsule via the tapped coil Tr2 (notice bizarre diode-connected transistors T2 and T3 for the rectifier!)

Anyway, the audio output from the capsule must be pin G going to the gate of the FET...but depending on what the "Bermuda Triangle" is, I don't see the FET doing any gain stuff- just an impedance buffer...so the white "thingy" must be active...CJ, isn't that a PS connection heading up parallel to the o/p transformer coil connecting on its way C12, D1/2

Interesting...

Mark