9 Jun
2006
9 Jun
'06
1:13 a.m.
On Fri, 9 Jun 2006, Tony Duell wrote:
Don't get me wrong, I love my old Tekky 555, but I
really don't think
this sort of instrument is good for a beginner who doesn't want to learn
how to repair valve circuitry and 'scopes in general. They are very
maintainable, and the manuals are excellent, but since they're over 40
years old, you are going to have to do some work on them.
My experiences with a 555 are *very* good. Found one on a scrap heap three
years ago, and someone picked the power valves (and the funny diode
2AS15-A) and their sockets out of the power supply (and cut the wires). It
took me some time to get replacement valves and rewire the power supply
around the sockets, but in the end, the scope worked like a charm! The
traces (it's a real dual beam, not dual trace) are sharper and finer than
everything else I've seen so far (mostly "modern" equipment like Hamegs or
HPs). We use it here e.g. to adjust the heads on RK05 drives or to measure
the signals on our LGP-30s (we have two working now!).
(Some pictures are on http://computermuseum-stuttgart.de/dev/tek555, you
can click on the pictures to see more)
Christian