I've got a nice, very portable, Vu-Data PS935 scope (check Google for info)
with probes that I'd be willing to sell - just upgraded to a BK 2160. If
anyone is interested, please drop me a line (private email), make me an
offer, whatever. I'll be busy with the dx contest till Sunday eve.
73, Barry N1EU
On Sun, Feb 19, 2012 at 12:32 AM, Charles P. Steinmetz <
charles_steinmetz@lavabit.com> wrote:
> Russell wrote:
>
> >Would be curious about thoughts from others who repair their own
> >gear about what minimum-required scope would be.
>
> This topic comes up periodically -- you can find some posts in the
> archives. Here is what I wrote in July 2010, with some further
> comments in brackets:
>
> >You will likely get a variety of responses. Here's my tuppence worth:
> >
> >As far as features and capabilities, a fully-featured scope will do
> >things you don't even know yet that you will want to do, and you'll
> >be very glad you got it when that time comes. For the most part, you
> >can just ignore the fancy features until you need them. The work-
> >horse has, for many years, been the 100 MHz dual-trace "portable"
> >bench scope with delayed sweep -- with very good reason. This
> >instrument can do the vast majority of what anyone needs, and they
> >are plentiful so prices are reasonable.
> >
> >First-quality scopes (Tektronix and HP) are available used for very
> >little money these days, so IMO anything less (Leader, B&K, etc.)
> >should only be considered if it's free. '80s- and '90s-vintage
> >scopes are cheap and plentiful, so there is no need to look at '70s
> >and earlier Tek and HP models, either. [There were some decent
> >models from Hitachi, Kikusui, and Philips, but they are all a full cut
> >below Tek and HP. I used to recommend the old Tek tube scopes,
> >but they are old enough now that you will spend more time fixing
> >them and chasing down intermittents than using them on other
> >equipment, and some parts are devilishly hard to obtain.]
> >
> >I am very partial to the HP 17xx series -- my 1742A, which I
> >originally purchased new in 1982 and which was on and working 10-12
> >hours per day for its first 15 years, still meets its specifications
> >and the screen looks as new. IME, HPs are generally easier and less
> >costly to repair than the equivalent Tektronix models (the Tek 465
> >series is particularly difficult and costly to repair). A
> >properly-working HP 1740A or 1742A can be had for $50-150. Even a
> >properly-working Tek 2465A digitally-controlled analog scope
> >shouldn't run more than $200-300 (the 2465Bs cost more because they
> >were the last of the line, but they aren't any more capable).
> >
> >So, unless the budget doesn't extend as far as $100, I'd get a 100
> >MHz dual-trace HP or Tektronix from a reputable seller.
> >
> >Most people use 10x probes almost exclusively, but for completeness
> >you'll probably want a couple of 10x and a couple of 1x probes. IMO,
> >name-brand (Tek or HP) probes are well worth the money over generic
> >probes. If you shop carefully, you can get good ones for $15-25 each
> >(though you'll see many listed for ten times that). Make sure the
> >compensation capacitor range on the 10x probes matches the input
> >capacitance of the scope (this is generally clearly marked on both
> >the scope and the probe).
> >
> >These days, you will also find digitizing scopes in the $200
> >range. However, to get similar performance (>/= 50 MHz "one-shot"
> >capability) and quality to the analog scopes mentioned above, you
> >would probably need to spend $400-$900 (the Tek TDS2xxx scopes would
> >be the ones to look at, IMO).
>
> The Rigol digitizing scopes have also been very popular lately. Note
> that most digitizing scopes put out all kinds of RF garbage, so they
> may not be suitable for working around receivers. Also, due to the
> limited bit depth of the A/D converters and low screen resolution,
> affordable digiscopes have noisy traces. On the other hand, you can
> make all kinds of measurements on the waveform, and often get a crude
> FFT of the input. And many of them will output to a thumb drive
> and/or computer so you can save copies of the data and/or traces easily.
>
> Asking prices on ebay for all of this stuff vary all over the map,
> and by far the large majority of listed items do not sell for their
> ridiculous minimum bids or reserve prices (check the "completed
> items" view to see what sold, and for how much). I have had
> reasonable success contacting sellers after their items were up for
> several cycles with no bids and making much lower offers.
>
> As always, it pays to study the instruction and service manuals for
> models you are considering, so you can interpret the listing photos
> properly and ask any questions you need answered to help determine
> the working condition as best as you can from a distance.
>
> Finally, let me stress once again the importance of good probes. You
> may need to wait a while to get genuine Tek or HP probes at a good
> price [$15-35 each, complete with ground leads and spring hooks], but
> the effort will be well worth it. Make do with some cheap
> substitutes (Pomona, etc.) until then.
>
> Best regards,
>
> Charles
>
>
>
>
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