Re: 576 erratic brightness

Chuck Harris

I think the issue isn't the added diode, but rather the series
of manuals that didn't make the box outlines bold, and break them
around the terminal points that were denoted by a black dot.

In those few manuals, and the 576 manual found on is one,
the box outline was the same width line as the circuit wiring, and
the dots were slightly larger than the connection dots.

When the formerly blue, outline boxes are printed in black, they
look like some very strange, nay, insane, circuit connections. In
simple places like the intensity pot in question, one might think
that they were actual wiring, and the pot was redundant.

In other places, where the outline box crossed all of the leads on
a power supply, and made it look like all of the power supply outputs
were shorted together, one gets the idea fairly quickly...

The tektronix blue color choice used to be quite a problem back when
all copies were made on the old xerographic process copier machines,
as the copier drums weren't at all sensitive to blue light.... which
caused the blue lettering to totally disappear in the copy.

In scans where the person scanning the schematic chose "B&W Line art"
as the scanning method, a rigid threshold is used to decide whether
a point on the paper is white or black, and the blue lines either
disappear as being below the threshold, or are totally black when
they are above the threshold.

-Chuck Harris

hahi@... [TekScopes] wrote:

Can somebody with a paper copy of the manual upload a scan or a photo
As Chuck pointed out Tek often used print in blue to indicate changes on schematics.
However in this manual the change was instead in weak grey. It is an original manual
and not a scan rev 7-83. In the newer manual I have the print is even weaker.

You can find a photo of the page here:


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