Sennheiser Power Supply Schematic Symbol?

[Cosmolac]

I was looking to build this power supply for an mkh104 and was wondering what this symbol is, im assuming its an inductor(ferrite core?) but what are the dots on the side?
Ive spent a good amount of time trying to find another picture of the same symbol but no luck

 

[rock soderstrom]

Yes, it is an inductor. Dr is short for Drossel, german for choke/inductor.

I have seen such dots before, but have no idea what they stand for. Perhaps they are supposed to indicate the windings??

 

[Khron]

... Or a steel core (as opposed to air-cored), rather.

 

[Cosmolac]

Yes, it is an inductor. Dr is short for Drossel, german for choke/inductor.

I have seen such dots before, but have no idea what they stand for. Perhaps they are supposed to indicate the windings??

Thank you! Good to have confirmation, I would still like to figure out what the dots mean, ive seen similar ones on symbols for tapped wire wound resistors but dont think it would make sense for them to be taps in context

 

[rock soderstrom]

I would still like to figure out what the dots mean,

Me too, so I googled a bit but unfortunately found nothing. The icon is also outdated, pre-internet time. I'll check some old books tonight....

Maybe the core material is actually described with it???

 

[Cosmolac]

Found this other schematic, that uses the same dots to indicate the core(steel? Ferrite?)

 

[Ivan K.]

Hope you get more replies, but as far as I know, the dots just indicate the transformer core and nothing about the material used. Perhaps one of our German colleagues knows for certain.

 

[Tubetec]

These mics definately use ferrite inductors ,
If you look at the V72 schematic dashes are used to signify the core instead of dots . In radio schematics you often see the dotted inductor .

Ive been looking around at Sennheiser mic power supplies , found this schematic which makes a 48v supply from a 9 v battery and a 555 ic ,
Canford also do a mic power supply , very similar to the original Sennheiser , it also provides P12.P24.P48 and T(A-B) power as well as three position HPF and three positions of attenuation , very costly though .

I'm a bit unsure which type the two MKH416's I got are , one is all SMD and it looks like the 416 P48 version , the other an older through hole version with three large inductors , interference tube/case is missing from both , One has the KS-16 capsule the other KS15-41.

The national broadcaster here in Ireland is in the height of trouble just now , but thats another story.
The typical RTE mobile sound recordists back in the day carried Studer B67's and Sennheiser MKH mics , that was their standard methodology to record absolutely anything ,either music or spoken word .

There are it seems some fake MKH mics out there so be carefull and dont end up getting stung if you buy from ebay .

 

[rock soderstrom]

Unfortunately, I could not find anything helpful regarding the points on the old choke circuit symbol.

 

[Cosmolac]

These mics definately use ferrite inductors ,
If you look at the V72 schematic dashes are used to signify the core instead of dots . In radio schematics you often see the dotted inductor .

Ive been looking around at Sennheiser mic power supplies , found this schematic which makes a 48v supply from a 9 v battery and a 555 ic ,
Canford also do a mic power supply , very similar to the original Sennheiser , it also provides P12.P24.P48 and T(A-B) power as well as three position HPF and three positions of attenuation , very costly though .

I'm a bit unsure which type the two MKH416's I got are , one is all SMD and it looks like the 416 P48 version , the other an older through hole version with three large inductors , interference tube/case is missing from both , One has the KS-16 capsule the other KS15-41.

The national broadcaster here in Ireland is in the height of trouble just now , but thats another story.
The typical RTE mobile sound recordists back in the day carried Studer B67's and Sennheiser MKH mics , that was their standard methodology to record absolutely anything ,either music or spoken word .

There are it seems some fake MKH mics out there so be carefull and dont end up getting stung if you buy from ebay .
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Great info thank you!