[sdiy] Best scopes for the money, 2020?

Michael E Caloroso mec.forumreader at gmail.com
Wed Dec 2 00:13:35 CET 2020

When buying used 'scopes make sure it is from a seller who guarantees
100% functionality.

My 'scope workhorse is a Tektronix 7900 modular system.  The 7000
series were a popular system from the 1970s to 1990s.  The 7900 is a
base unit that accept plug-ins from a wide range of functionalities.
There are the usual vertical and time-base plug-ins of varying
bandwidth and features.  They also offered plug-ins like differential
amplifiers, universal counter/timer, spectrum analyzers, logic
analyzers, curve tracers, etc.  You could configure a measurement
system for any industry.

With four plug-in slots on a 7900 I could configure dual independent
'scope systems or single 'scope with four channels.  One of the
powerful features I found was combining 'scope setup with logic
analyzer.  While the 7D01 logic analyzer plug-in is rudimentary by
todays' standards, it was valuable for troubleshooting multiplexed
analog signals such as hybrid analog synths.  I could monitor logic
signals and configure the word recognizer at a specific memory
address, then route that WR output to trigger the 'scope horizontal
timebase to get a stable view of a specific analog control in a
non-repetitive multiplexed stream.

It was a long time ago but I think my investment in that 7900 system
was under $1000, included the 7900 chassis, probes, two 7A26 vertical
modules, 7B53/7B92 horizontal modules, 7D01 logic analyzer with DF1
formatter, 7D15 universal counter/timer, 7L5 spectrum analyzer.

My other 'scope is a Tek 2430.  It serves as a digital system with
storage capability.

One thing that novices neglect is scope probes.  The right ones make
all the difference in the world.  There are app notes online that
discuss probes.


On 12/1/20, Mattias Rickardsson <mr at analogue.org> wrote:
> Ingo Debus skrev:
>> > schrieb Brian Willoughby
>> >
>> > Vintage is better than modern.
>> For a scope? I definitely disagree.
>> One important feature of a scope is memory depth. Newer scopes have more
>> memory than older ones, for the same money.
> Memory?
> Sure, my Tek 549 and 564 are storage oscilloscopes with the novel technique
> of keeping the phosphor glowing and all, but they have some vacuum tubes
> replaced by transistors so I'm not sure I'd call them vintage. ;-)
> Jokes aside, old digital scopes can probably be seen as less useful and
> more hopeless than the slightly older analog scopes they replaced (and once
> were better than).
> And if they’re really old they have a disk drive rather than an USB jack…
> Disk what? (-:
> /mr

More information about the Synth-diy mailing list