Tektronix 475 oscilloscope

The Tektronix type 475 is a solidly built scope, a real workhorse from the 1970-ies. The model dates from about 1972. Although completely solid state, it does have a fan for cooling.

This scope has been built around 1972. The vertical bandwidth is 200 MHz, which is really good. It has a delayed timebase with several trigger modes.

The 475 is the big brother of the famous 465 that had a 100 MHz bandwidth.

I bought my 475 in august 2011 on an Internet second-hand-stuff site. It had belonged to a Dutch radio ham. When I switched it on, it just worked, just as promised. The spot is slightly fatter than on the Tek 2235 scope but the image is very good.

I have used this scope as my main scope since I bought it. There are many screen photos from it, e.g. on my guitar combo project page.

In 2019, while I was doing measurements on an amplifier project, the scope suddenly started ejecting foul smelling smoke. The smell of burned epoxy made me fear this could be the power transformer or the HV transformer, but it turned out well: it was just a tantalium electrolytic on one of the power supply rails that had overheated.

After replacing the capacitor, my Tek475 was working fine again. I replaced several other electrolytics, they are rated for 16V, sitting on the 15V power rail, so they don't have much margin.

I am very happy to use this iconic scope so it remains on my workbench.