I'm trying to troubleshoot an old analog oscilloscope (Metrix ITT instruments OX 725), which seems to come from the late 1980s in France.

There is (part of?) a service manual with circuits diagrams available online (https://archives.doctsf.com/documents/afficher_document.php?num_doc=100437&num_fic=1), but I'm having a hard time piecing together how the circuits are actually connected.
In particular, there seem to be three different symbols used for 'this part connects to a different circuit' that I can't identify. Does anyone know what they mean and what the difference between them is?

These are the most common ones.

Pill shaped symbol

These kind of look like arrows. Most of them (but not all) have markings like +12A or -12V and point according to the sign of the number, so maybe they indicate connections to the power supply and some are misprinted?

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These look similar to modern connector symbols, but not quite the same.

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As an example, here is one of the schematics containing all three kinds of symbols: enter image description here


2 Answers 2


A different opinion from Voltage Spike's...

Pill shaped - These are more likely connector pins. Note the J#/Pin# format, as in J5 10.

Flag shaped - I agree that these are power connections. I don't think the arrow indicates current flow, but rather source/destination (which may be the same a current flow, I guess).

Double-angled-bracket-shaped (double arrow heads?) - I think these are off-page connectors, for a multi-page schematic.


My guesses:
Pill shaped - These are probably solder jumpers or resistor jumpers, or even 0.1" header jumpers.

Flag shaped - defiantly VCC/powerrail markers. The arrows could indicate direction of current flow

Double-angled-bracket-shaped - Not sure either, would need to see more, probably a test point or a different kind of power rail, maybe high voltage. Could even be comm

  • 1
    \$\begingroup\$ Double arrow ones may indicate that the signal moves to another sheet. All of them in the example schematic have diamond with a reference number next to them (e.g. <F3>, with the current sheet being <F2> according to the bottom left. Maybe they use >> for signals and => for power. \$\endgroup\$ Commented Nov 4, 2023 at 0:09

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