Maker Pro
Maker Pro

Circuit symbols Identification

MFRANK

Aug 26, 2018
4
Joined
Aug 26, 2018
Messages
4
I have an old Amp circuit schematic which has symbols on it that make no sense to me. Can anyone with knowledge of these please help with a description of their meaning/connection. The symbols are lines connected to circles and ovals connected to a line with another line going through that oval. I have not been able to find these symbols on any search. I have included a pdf file with the symbols on it to assist you in identification.
 

Attachments

  • Circuit.pdf
    11.3 KB · Views: 53

Minder

Apr 24, 2015
3,478
Joined
Apr 24, 2015
Messages
3,478
That is an indication that the conductor has a shield and the conductor is connected to it.
M.
schematic-symbols_s.jpg
 
Last edited:

davenn

Moderator
Sep 5, 2009
14,254
Joined
Sep 5, 2009
Messages
14,254
That is an indication that the conductor has a shield and the conductor is connected to it.

You had better clarify that bit for the OP, it doesn't quite make sense ;)

the way you have worded it infers that the centre conductor is shorted to the shield
which, of course, isn't correct
 

MFRANK

Aug 26, 2018
4
Joined
Aug 26, 2018
Messages
4
Thanks for the reply Mider, but your pictorials (seen these Previously)or explanation has made me none the wiser and I still think you missed what I was trying to find out. From what I observed on the amp connections, shielding has nothing to do with it. Sorry.
 

duke37

Jan 9, 2011
5,364
Joined
Jan 9, 2011
Messages
5,364
The symbol you show looks very like the symbol for 'shielded wire or coaxial cable'. Are you sure that the cable has no shield?

Post a picture of the appropriate cable with connection.
 

Minder

Apr 24, 2015
3,478
Joined
Apr 24, 2015
Messages
3,478
Thanks for the reply Mider, but your pictorials (seen these Previously)or explanation has made me none the wiser and I still think you missed what I was trying to find out. From what I observed on the amp connections, shielding has nothing to do with it. Sorry.

The device the wire is connected to appears to be a phono type jack, these typically are wired with shielded cable!!
M.
 

davenn

Moderator
Sep 5, 2009
14,254
Joined
Sep 5, 2009
Messages
14,254
Thanks for the reply Mider, but your pictorials (seen these Previously)or explanation has made me none the wiser and I still think you missed what I was trying to find out. From what I observed on the amp connections, shielding has nothing to do with it. Sorry.


well if you think we ALL are misunderstanding what you are referring to
THEN PLEASE enlighten us and red circle the specific part on the diagram that you are referring to

TILL THEN NO-ONE ELSE RESPOND
 

MFRANK

Aug 26, 2018
4
Joined
Aug 26, 2018
Messages
4
20180827_091501.jpg I have posted a picture of the connections. So please explain if these connections match the circuit for Sus & Vib/Trem inputs. I still think there is no shielding just 2 terminals per connections. Thanks to all that have posted replies.
 
Last edited by a moderator:

davenn

Moderator
Sep 5, 2009
14,254
Joined
Sep 5, 2009
Messages
14,254
I still think there is no shielding just 2 terminals per connections. Thanks to all that have posted replies.

OK,
It is wise not to tell us more experienced ones what you think we don't know when you don't know ;) ;) tends to be a little embarrassing ;)
so as we all said, the symbols in the circuit diagram represents shielded/screened wires
I have pointed them out on your photo and circuit diagram that I have annotated

firstly the circuit symbol from Minders collection

screened lead symbol.jpg

Annoting them in your circuit diagram

screened leads.JPG


annotating them in your photo

20180827_091501.jpg


Those 2 white cables and 3 grey cables all have screens
The grey cable on the far right is a twin core screened cable and from the circuit diag. appears to be the reverb socket
All the screens/shields will go to the 0V rail

OK so now that is clarified, is there still another ID problem that we can help with ? :)


Dave
 
Last edited:

MFRANK

Aug 26, 2018
4
Joined
Aug 26, 2018
Messages
4
Thanks Dave and others,
I see what you mean by screened now. I thought it meant 2 terminals with aluminium/meshed wire over the top of them, inside the plastic insulation material, but in this situation the meshed wire is being used as the other terminal.
Sorry for the confusion.
 

duke37

Jan 9, 2011
5,364
Joined
Jan 9, 2011
Messages
5,364
The screen may be connected at both ends and may be one ended only. Sometimes the neutral signal wire is connected to the screen.

In your picture at the bottom right show clearly three connections, others show only two.
Someone has spent quite a time on getting the earthing done properly to reduce hum.
 
Top