7704A Repair and modules. 7B53 in faster frames


ashtonb@...
 

--- In TekScopes@y..., dhuster@p... wrote:
There's not a darned thing wrong with using a 7B53A in a 7704 or
7704A. It's the 7B92/A that you can't easily use on lower
bandwidth
scopes only because they can't handle the faster sweeps. And
7B53A's
are so plentiful that they should be cheap. Having to come up with
and pay for a pair of 7B7x or 7B8x is a lot more difficult and
expensive -- and you'll need two service manuals instead of one.
And
the 7B53A leaves a horizontal compartment free for a counter or DMM.
Seconded - before I acquired 7B87, later -92As via a package deal: a
7B53 in my 7854 (400 MHz nom) scope worked fine. At fastest sweeps,
with a known ~700 pS risetime pulse - yes, you can see some combo of
delay-line (absent or mismatched?) aberrations on trace start; IIRC
maybe an almost double-pulse clearly "not happening". So all one
needs to remember is: Stay away from <10 nS/DIV - it isn't 'sposed
to be linear down there.. Audio is almost DC. And as Dean observes,
the built-in dual timebase gets you delayed sweep w/o wasting a
compartment.

(Still.. it's fun to see the readout say, "500 pSec" on the -92s -
and realize it's even true within 3-5% !! One gonzo ramp generator,
to use the technical term ;-) Maybe sometime I can steal a 7104 / 7B10
and see: "200 pSec/DIV" !! As Spock might say.. fascinating


Ashton


dd@...
 

Seconded - before I acquired 7B87, later -92As via a package deal: a
7B53 in my 7854 (400 MHz nom) scope worked fine. At fastest sweeps,
with a known ~700 pS risetime pulse - yes, you can see some combo of
delay-line (absent or mismatched?) aberrations on trace start; IIRC
maybe an almost double-pulse clearly "not happening".
Yes, that's what I was talking about... I know it's written up in one of
the manuals or catalogs, but I can't seem to locate it at the moment.
I guess I'm just picky :-) On the other hand, 7B8xs are pretty cheap.

(Still.. it's fun to see the readout say, "500 pSec" on the -92s -
and realize it's even true within 3-5% !!
Most of them will give a solid trigger on a 1GHz signal - a tribute to the
power of tunnel diodes.


 

--- In TekScopes@y..., dd@a... wrote:

(Still.. it's fun to see the readout say, "500 pSec" on the -92s -
and realize it's even true within 3-5% !!
Most of them will give a solid trigger on a 1GHz signal - a tribute
to the
power of tunnel diodes.

... but the 7B92A SN B070000&up has no tunnel diodes anymore.


Jorgen
dj0ud