Circuit Polarity

[Zerikin]

How can I consistently identify the polarity of the posted circuits here? Some of them are labeled +9v supply which makes it clear but I've seen several with just 9v listed that appear to also be +9v circuits. For example the Gainster has the supply voltage directly to the Vcc+ pin of the IC so I assume its a +9v on the supply even though the supply simply says 9v.

[rocket88]

If the layout is -9V it's always written as such and/or it's in the notes and in the post, at least on the main page, otherwise it's +9V. I usually write +9V its not really necessary, I just do it as a force of habit. Luckily there aren't many layouts that use -9V, and mostly appears in older circuits that use Ge trains intros before the switch to Si transistors or modern layouts that are faithful reproductions of old Ge circuits.

[Muadzin]

In my experience its always best to never assume 'surely they will understand this' and leave something out. Because that's when you will confuse someone. Always best to give all the information, even when you think its unnecessary.