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-----Original Message-----
From: jbarnes [mailto:jbarnes@...]
Sent: Friday, February 27, 2004 9:14 AM
To: tekscopes@...; Bruce Lane
Subject: Re: [TekScopes] Recommendations?


I would second Bruce's comments on a local purchase. It is very good on
your first scope to be able to play before you buy.

You can make sure that tube is good etc.

A dealer selling a $200.00 scope on ebay can not afford to spend much more
time than plugging it in and seeing if there is is a trace. To properly
check scope take around a hour, to verify the calibration much longer.

Try and find a local source for your first scope.

Remember you need a scope to fix a scope !!!

Regards,

John


---------- Original Message ----------------------------------
From: "Bruce Lane" <kyrrin@...>
Date: Fri, 27 Feb 2004 07:48:03 -0800

> In that price range, you should be able to do pretty well. Pay
attention to any local ham radio swap meets, electronic surplus stores, or
Ebay as a last resort (can you tell I believe in supporting local efforts
first?) ;-)
>
> You don't specify if you're looking for a "lab" or benchtop 'scope,
or if a luggable is more your style. In the case of the benchtop systems,
the 7000 series is probably still one of the best buys around. Tek made them
for over two decades; Mainframes and plug-ins are still pretty widely
available, and they're one of the most versatile 'scope series ever to hit
the industry.
>
> Benchtops first.
>
> For signals up to 100MHz: 7603 mainframe, 7B53A timebase, 7A26
vertical.
>
> For signals up to 200 or so MHz: 7704 or 7704A mainframe, 7B80 or
7B85 timebase, 7A26 vertical (it's good up to 250MHz).
>
> Keep in mind that, for the following frames and plug-ins, you may
well exceed your stated price point.
>
> For signals up to 400-500MHz: 7854, 7834 (storage), 7904, or 7904A
mainframes, 7B92A AND 7B85 timebases, 7A24 vertical (50 ohm inputs, suggest
using a FET probe), 7A26 (you can still use them in the higher-bandwidth
mainframes) for high-impedance (1M-ohm) input. The 7A24 goes up to 400MHz,
and you can also try for a 7A29.
>
> For signals up to a gig: 7104 mainframe, 7B10 AND 7B15 timebases,
7A29 vertical for high-frequency signals, 7A24 or 7A26 for lower-end stuff.
>
> Note that, if you get a storage-type frame (such as the 7834), the
CRTs are very susceptible to damage (burn-in and other nastiness). Unless
you have an explicit need for an analog storage 'scope, it is probably best
to avoid them.
>
> Most digital-type storage 'scopes do not suffer from the same CRT
fragility problems. This would include units like the 468, many of the 11000
series, the DSA600 series, and pretty much everything that comes after it.
>
> For a 'luggable:' It's still pretty hard to beat the 465, 475, and
485 series. The 475A will go up to 250MHz. I should also mention that the
460 and 470 series were widely used as field-service 'scopes by many a
computer tech in the late 70's through the early-to-mid 80's. Your price
point should work for pretty much anything in this series with the possible
exception of a 485, or a mint-condition specimen of the other series.
>
> Happy hunting.
>
>* REPLY SEPARATOR *
>
>On 27-Feb-04 at 15:10 John wrote:
>
>>I am looking for a good reliable used Tek scope to learn on and use
>>for amateur radio repairs. I see many up for sale on eBay and would
>>welcome any advice on which I should consider, and which should be
>>avoided due to common problems, or inavailability of parts. I would
>>like to spend up to $200, but would possibly consider going as high
>>as $350 if there is a compelling reason to do so. Thanks in advance
>>for your advice and counsel.
>>
>>John
>>
>>
>>
>>
>>Yahoo! Groups Links
>>
>>
>>
>
>
>-=-=-=-=-=-=-=-=-=-=-=-
>Bruce Lane, Owner & Head Hardware Heavy,
>Blue Feather Technologies --
>kyrrin (at) bluefeathertech do/t c=o=m
>"If Salvador Dali had owned a computer, would it have been equipped with
surreal ports?"
>
>
>
>
>
>Yahoo! Groups Links
>
>
>
>
>
>


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