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Re: First post - Hello and a question

Johnny Chapman
 

Thanks for the post Ash!

Check the specs on the Sencore SG80. I believe it to
be a bit better and a younger product by maybe ten
years. I hardly use it, but when needed, BAM! I
generally am brand loyal almost to a fault!

I've first seen them in the install/maintenance bays
of GM dealerships. AC/Delco is the parent company of
Rockford-Fosgate!




____________________________________________________________________________________
Yahoo! Music Unlimited
Access over 1 million songs.
Re: First post - Hello and a question

Stefan Trethan
 

On Thu, 08 Feb 2007 03:21:49 +0100, arthurok <arthurok@...> wrote:

because of modern technology
you arent paying very much for all those modes
the software programming is amortized over a tremendous number of units

And they don't seem to test the software at all, ever, so that saves lotsa money too! ;-)

ST
Re: Japnease Transistor

Petrosilius Zwackelmann
 

Hi,

it's available in germany for 0.52??? each.

BR,
Michael

-------- Original-Nachricht --------
Datum: Thu, 08 Feb 2007 07:50:38 -0000
Von: "m8jpk" <ttesenq@...>
An: TekScopes@...
CC:
Betreff: [TekScopes] Japnease Transistor

Hello All
I am trying to source Some Japnese transistors or get some equivalent
info. ( 2SC2909)
Any help most welcome
M8JPK
--
"Feel free" - 5 GB Mailbox, 50 FreeSMS/Monat ...
Jetzt GMX ProMail testen:

UK owner of Tek 2465 sought

Jon Nicoll
 

Hello all
are there any UK-based members out there with a Tek 2465?

As mentioned in a long post a couple of weeks ago I'm tryingto track
down a problem with mine. Currently my best bet is the Z-axis Hybrid
U950, p/n 155-0242-01. I will by a new one of those if need be, but
I'd like to be more sure of my diagnosis(*). If someone would be up
for trying my Hybrid in their 'scope and confirming that it is the
problem, I'd be very grateful. Postage etc. covered of course. Please
get in touch if you could help me with this.

Thanks
jon N

(*) I've checked the DC voltages on J119 which are all within limits
on a DMM, and the p-p ripple is fine on each voltage. The grid bias
adjustment alters the brightness fine, & it becomes apparent that the
front panel intensity control has *no* effect. The intensity control
does alter the output of the Display Sequencer Chip, but the waveform
#65 in the service manual (zBout from the hybrid) sits at around 3V
regardless of the position of the intensity control)
Re: old computers

Ashton Brown
 

Heh.. cut teeth on a PDP-8 - we were first to use a "(mini)computer" to control the guide field of a large particle accelerator.
Here was this 'bitchin' lookin heavy/small Thing with smoked-plastic covers: blinking at you. In Octal.

The DEC "manual" was written for those who already knew what was in the manual. I had to start with a blackboard and Boolean Algebra book, on through RIM loader, wft-is-'assembly'?, wtf is an 'ALU', octal etc. I realized I'd never be (want to be) a programmer, but at least learned how-to: create a program to print out a BCD encoded paper tape on the ASR-33. Valuable lore.. from machine language through assy and compiling my source on the CDC-6600. And quite enough por moi, thankyouverymuch.

It's always useful to suffer through the basics.. then no snot-nose wannabe-someday 'IT'er can baffle you with BS.. 'explaining-away' some latest Redmond buffer overflow - built in by some bored committee of drones chained to a cubicle 10 years ago: and today -?- exposing you to the spoofer from Belgrade. Crapware has now infected the entire World. It will take a generation to undo what autistic/arrogant Billy has done to us all. For mere greed via mere hubris.

Still have a pristine Otrona??? CP/M portable w/ 5" green screen - operable last year I looked. Any takers?
(Word Star mnemonic codes inculcated into fingers.. still beats stupid-mousing distractions and M$ Word style eye candy -- for sheer speed of text entry -- for any touch typist. ^KS - saves your work, etc. You never forget, as their mnemonics made logical sense immediately - and your hands never left the home row.)

Fat chance of getting a 100 GB HD onto that CP/M OS, though :-/



Chuck Harris wrote:

arthurok_2000 wrote:

is anyone in this group other then dave wise
into old computers??
I have an old PDP8/E with a TU56 dectape drive. In the
spirit of tektronix, I am looking for a 4010 to use with
it.

-Chuck Harris
Japnease Transistor

m8jpk
 

Hello All
I am trying to source Some Japnese transistors or get some equivalent
info. ( 2SC2909)
Any help most welcome
M8JPK
Re: old computers

J Forster
 

im quite familiar with the lsi11 and q bus
never was a great fan of the data general nova machines.

They had nice features and some crocks. The 'increment memory location'
via DMA was useful for making multi-channel analyzers and photon
counting imagers. Their use of mostly standard parts was a real plus.
You could make good money by buying a minimally stuffed board and
loading it fully, once you knew how. The company management sucked, top
to bottom, with the sole exception of an ex-Tek sales engineer.

FWIW,
-John
Re: AM501 Stuff (op-amp references)

Ashton Brown
 

Note that there are BNC adaptors on an extruded oval alloy shield which shrouds right down to the faceplate plane (at least hP sold these - probably others.) Wish I had a few more of these. With the shield physically connected to the black/common binding post, you have ..almost.. a fully shielded 'can'. Worked fine for the few-???V noise floors of the various sensitive good AC meters du jour.

(My lovely Racal-Dana 9300, good down to Boltzmann noise and to a phenomenal MHz top-end RMS, ~20 MHz at 6:1 crest IIRC? - natch was already BNC equipped.) Very handy with it's output amp sent to an accurate DC DVM, when you care about <0.1% relative levels.

Ergo "binding posts" need not be a huge handicap - anywhere near audio freq.

Ashton


J Forster wrote:

From: "jones_chap" <jones_chap@...>

[snip]

Interesting note about "anything with banana plugs" is that when
playing around with the AM501 plugins was a sensitivity of the output
based upon the proximity of my hand near the jacks. Wild and crazy
things would happen as I got anywhere near 'em, sorta. One was much
more sensitive than the other.

The noise, etc. is capacitively coupled to your circuitry. Reduce the
values of the components in the FB loop and it will go down or use a
grounded aluminum foil shield.
tek 4051 computer

arthurok_2000
 

are those ever availible?
looks like alot better unit then a comparable hp 9825a
and the tek basic is fantastic for its day
Re: First post - Hello and a question

Greg_A
 

For audio band distortions you just need what is called Wave Analyzer (in
other
words spectrum analyzer) in 5Hz -50kHz. I own one with some same spare - HP
analyzer for audio band.
Any scope is not capable to "see" small distortions....

Greg


At 04:14 PM 2/7/07 -0500, Kuba Ober wrote:


I was talking about "aligning" audio circuits, e.g. adjusting operating
points of various stages, checking response, etc. Not about any sort of
RF work.

If I wanted to see a nonlinearity of a stage in an audio power amp, for
example, it'd be nice to believe that the scope's vertical system is
linear enough, etc. Same goes for step response: hard to do with a scope
that may well distort even a perfect square wave.
Anyone who is at all capable of making those kind of measurements
would surely measure the input square wave first. If it looks like
a square wave, then the scope is good enough for the task.
The input will look like a square wave even with a badly nonlinear vertical
channel. The output "square" wave will then typically be much slower than
the

input one you fed to your system. With nonlinear vertical, the slower
transitions on the output square wave will look distorted, and you may
end up

chasing ghosts, especially if the audio amp alignment procedure mentions
e.g. "adjust Rxxx for output transitions to be smooth".

I just don't believe in using unchecked instruments, and a reasonable way
to
check a 7603 with plugins is to use the classic calibration trio in a
TM503,
plus a mainframe standardizer.

How on earth can anyone recommend using an unchecked, unknown scope to a
newb

is beyond me. Newbs tend to misunderstand limitations of instruments they
use, so they are very likely to just blindly trust the trace, even if
someone

experienced would check things twice first. You know, things like using too
much or too little of vertical deflection, not centering the signal and
hunting differing rising/falling edge aberrations, and so on. It's just
very
easy to hit those on an uncalibrated scope methinks.

Cheers, Kuba



Emacs!
Re: First post - Hello and a question

J Forster
 

because of modern technology
you aren't paying very much for all those modes
the software programming is amortized over a tremendous number
of units

True, but many (most) users REALLY don't want to have to read a 50+ page
manual to make a piece of toast or a cup of coffee. My reply was more
directed at "Why make it simple when complicated also works well"

How many of the VCRs you've seen over the last few years just sit and
blink 88:88:88 at you? Too many, IMO. I no longer bother to set mine
after a power fail.

-John
Re: old computers

Hugh Prescott
 

Everything from a wire wrapped 1802, low serial # Altair, early IMSI etc.

Most will still power up.

Hugh





arthurok_2000 wrote:

is anyone in this group other then dave wise
into old computers??
Yahoo! Groups Links
Re: old computers

arthurok
 

im quite familiar with the lsi11 and q bus
never was a great fan of the data general nova machines.

----- Original Message -----
From: J Forster
To: TekScopes@...
Sent: Wednesday, February 07, 2007 10:36 PM
Subject: [TekScopes] old computers


is anyone in this group other then dave wise
into old computers??

Yes, but not actively. Most of the Data General Nova line, but not
eclipses. Also some LSI 11s in the Tek DPO. Also Multibus and some VME.

-John
old computers

J Forster
 

is anyone in this group other then dave wise
into old computers??

Yes, but not actively. Most of the Data General Nova line, but not
eclipses. Also some LSI 11s in the Tek DPO. Also Multibus and some VME.

-John
Re: old computers

Dave Casey
 

Interested, yes. Knowledgable, no.

Dave Casey

----- Original Message -----
From: arthurok_2000
To: TekScopes@...
Sent: Wednesday, February 07, 2007 8:47 PM
Subject: [TekScopes] old computers


is anyone in this group other then dave wise
into old computers??
Re: old computers

 

Chuck Harris <cfharris@...> wrote:
arthurok_2000 wrote:
is anyone in this group other then dave wise
into old computers??
I have an old PDP8/E with a TU56 dectape drive. In the
spirit of tektronix, I am looking for a 4010 to use with
it.
I *had* an LI-1000E clone of an IBM 1130, complete with 29M
12 platter top loading disk packs. It was card input (had the 029
keypunch, too) and had a 600lpm band printer. 'twas operational
in my living room. My oldies these days are considerably smaller
and newer. PDP8's & 11's are wonderful pieces of history. In fact
pretty much anything DEC made is nifty.
-ls-
Re: old computers

Chuck Harris
 

arthurok_2000 wrote:
is anyone in this group other then dave wise
into old computers??
I have an old PDP8/E with a TU56 dectape drive. In the
spirit of tektronix, I am looking for a 4010 to use with
it.

-Chuck Harris
old computers

arthurok_2000
 

is anyone in this group other then dave wise
into old computers??
Re: First post - Hello and a question

Chuck Harris
 

Kuba,

It is simple, very few newbies can afford to buy top dollar
calibrated equipment.

I have had the luxury of living near a surplus dealer that literally
has gone through tens of thousands of tektronix, HP and other scopes.
Of the Tek scopes, virtually all work, or are only slightly broken.
Typically the failures are mechanical (someone broke all the switches
on purpose), or the odd failed tantalum.

Every 7000 series scope that I have pulled out of his pile has worked
near perfectly after I have fixed the bad tantalums. Most were in perfect
calibration. As a caveat, I never pulled out any that had been smashed,
or were incomplete. There were so many, why bother with the trash?

So, I can without reservation recommend to a newbie that 7603 he finds
on Ebay that shows a clear waveform on the screen. Particularly if it
comes from a seller that has a reputation for selling checked out stuff.

Use an unchecked scope? Nope, you will have to look at some basic
signals. The calibrator will easily tell you if the amplifier is behaving
linearly. How? Simple, step through the calibrator output values, and
watch where the square wave's tops and bottoms hit on the graticule lines.
Set a 1cm square wave, and use the vertical controls to move it from the
bottom of the screen to the top, noting the size of the square wave.
Trying different V/cm values on the same voltage square wave, and note
the size changes. It's not complicated, and it is not at all hard.

If you do these simple things, your scope will be good enough for audio
work, and most other work.

-Chuck Harris

Kuba Ober wrote:

I was talking about "aligning" audio circuits, e.g. adjusting operating
points of various stages, checking response, etc. Not about any sort of
RF work.

If I wanted to see a nonlinearity of a stage in an audio power amp, for
example, it'd be nice to believe that the scope's vertical system is
linear enough, etc. Same goes for step response: hard to do with a scope
that may well distort even a perfect square wave.
Anyone who is at all capable of making those kind of measurements
would surely measure the input square wave first. If it looks like
a square wave, then the scope is good enough for the task.
The input will look like a square wave even with a badly nonlinear vertical channel. The output "square" wave will then typically be much slower than the input one you fed to your system. With nonlinear vertical, the slower transitions on the output square wave will look distorted, and you may end up chasing ghosts, especially if the audio amp alignment procedure mentions e.g. "adjust Rxxx for output transitions to be smooth".
I just don't believe in using unchecked instruments, and a reasonable way to check a 7603 with plugins is to use the classic calibration trio in a TM503, plus a mainframe standardizer.
How on earth can anyone recommend using an unchecked, unknown scope to a newb is beyond me. Newbs tend to misunderstand limitations of instruments they use, so they are very likely to just blindly trust the trace, even if someone experienced would check things twice first. You know, things like using too much or too little of vertical deflection, not centering the signal and hunting differing rising/falling edge aberrations, and so on. It's just very easy to hit those on an uncalibrated scope methinks.
Cheers, Kuba
Yahoo! Groups Links
Re: First post - Hello and a question

arthurok
 

because of modern technology
you arent paying very much for all those modes
the software programming is amortized over a tremendous number of units

----- Original Message -----
From: J Forster
To: tekscopes
Sent: Wednesday, February 07, 2007 6:16 PM
Subject: Re: [TekScopes] First post - Hello and a question



customer dosent want to pay for complicated

Tell the Japanese TV, VCR, and cell phone designers that. My TV has more
programming modes than a 757.

8=))

-John
182761 - 182780 of 208746