18 May
2007
18 May
'07
11:01 p.m.
On Fri, 18 May 2007, Paul Anderson wrote:
My workshop runs on old test gear too, apart from the LogicDart (and
that, acutally, is 10 years old now). Basically, I have the choice
between new and popr quality or old and good quality (I can't afford new,
good qaulity instruments). Th specs on paper might be about the same, but
I'll bet the older instruments from the likes of Tektronix and HP are
more likely to meet said specs than the modern non-name stuff.
I have a Tek 555 here with a good assortment of plug-ins. And a Solartron
portable 'scope, also valved. It's fine for head alignments, etc. And you
all know of my love of the HP5245 counter.
I came across a good looking 551 and not so good
looking 555 and some carts
and plug ins. I have no interest in them. If anyone has any interest,
contact me off list and I'll submit offers for you. The current owner does
not ship, but I can try to.
I think these Tek scopes aren't off topic at all. We use a Tek 555
regularly at out museum to repair/align our computers. RK05 head alignments and LGP-30 repairs are better done with old
Tek scopes than
with modern digitizing scopes, at least that's my experience.
Although we are a computer museum, we started to collect/rescue old
measurement equipment that is related to computers, i.e. scopes, logic
analyzers, DMMs, tube testers and so on. For example, we use a Funke
RPG4/3 for testing the tubes in our LGP-30s.
I have a vlave tester than I use -- an AVO Mk 4 -- and one that I must
get round to repairing -- a Mullard High Speed Valve Tester. The former
is a preoper mutual conductance tester, and is an excellent instrument,
the latter is an emissions tester AFAIK, but is interesting in that you
have a 'pucnhed card' (actually a piece of SRBP with holes in it) that
you slot into the instrument. An array of contacts (I think 10*14) senses
the holes and sets the electrode voltages and pin connections for the
particular valve under test.
Alas none of my computers (or calculators) are old enough to need a valve
tester to repair them
-tony