开云体育

Andy,

Stan's right. I found a 555 on a dump, full of leaves and dirt. I stripped it down, cleaned all the waterproof bits in the bath, dried it with an airline followed by 3 hours at 60C. When I eventually got it all back together and switched it on, guess what? That's right - worked straight away.

It's worth the effort; these are lovely bits of engineering.

Richard.


Stan and Patricia Griffiths wrote:

Anyone have any source available for TM system blank plates, or the eject
button only?



/Lars



-----Ursprungligt meddelande-----
Fr?n: TekScopes@... [mailto:TekScopes@...] F?r
jones_chap
Skickat: den 31 december 2006 13:16
Till: TekScopes@...
?mne: [TekScopes] DP501 Schematic & Parts List Please



Looking for DP501 Parts List & Schematics. Anyone have it in pdf,
html, or djvu format? If so, please email to me. If larger than
maybe 10MB, encoded, then send to mlcgray@bellsouth.
<mailto:mlcgray%40bellsouth.net> net.

I'd really like to take a look at this plug-in!

Thanks.





[Non-text portions of this message have been removed]

Found @ BAMA! ;) 4mbyte djvu file. A beautiful scope btw.





-----Ursprungligt meddelande-----
Fr?n: TekScopes@... [mailto:TekScopes@...] F?r
jeep534
Skickat: den 31 december 2006 12:42
Till: TekScopes@...
?mne: [TekScopes] new to me 310 A scope



I have just aquired a 310A scope SN 023989 and I would like to find
the manuals for it. it is in unknown condition. I would like to clean
it up and use it. Hopefully I can get it to work properly ( with a lot
of help from you guys of course)

Happy Hunting
archie =) =) =)





[Non-text portions of this message have been removed]

Looking for DP501 Parts List & Schematics. Anyone have it in pdf,
html, or djvu format? If so, please email to me. If larger than
maybe 10MB, encoded, then send to mlcgray@....

I'd really like to take a look at this plug-in!

Thanks.

I have just aquired a 310A scope SN 023989 and I would like to find
the manuals for it. it is in unknown condition. I would like to clean
it up and use it. Hopefully I can get it to work properly ( with a lot
of help from you guys of course)

Happy Hunting
archie =) =) =)

First, does there exist a front cover for the 492 Spectrum Analyzer,
and, if it does, where can I get one ?

You'll see them on eBay every once in awhile, or for that matter,
Deane Kidd may be able to put his hands on one. There is an older-
and a newer-style (all plastic) cover; either will fit.

The innermost surface of the newer covers have a cool Easter egg
(raised thermoplastic signatures of several dozen Tek employees from
the spectrum-analyzer product group). The foam-rubber liner will most
likely be in better condition in these as well.

Other than that, they will both work OK. They are really just dust
covers, though. Under no circumstances should you ever ship a
49x-series analyzer with either front cover in place. The older-style
covers are likely to come loose and bash the heck out of the front
panel. The newer-style covers are lighter, but their flexible plastic
latches are prone to breakage if any force is exerted on them during
transport.

-- john, KE5FX

Hi Stan,



As i see this new thread, i always asked myself about the use of Kalotron in
the PSU of the 555 ? What’s the big iron potted case too ?



I broke a pair of those PSUs many years ago and those are somewhere in the
basement . I never saw the schematic .

I have a 551 working that doesnt contain these parts .



Ah, happy new year to all of you !

And long life to our old old tubed scopes ;-)

Pierre





_____

De : TekScopes@... [mailto:TekScopes@...] De la part
de Stan and Patricia Griffiths
Envoyé : dimanche 31 décembre 2006 03:10
? : 'faustian.spirit'
Cc : TekScopes
Objet : RE: [TekScopes] Re: Bringing up a 555



Hi Andy,

You asked about connectors for extender cables. There are three possible
extenders you could be talking about: 1) vertical plugin, 2) timebase
plugin, 3) power cable from mainframe to power supply. I am sure I have
connectors that I can sell you to build extenders for either type of plugin
for a couple of dollars per connector. Most of what I have have been
salvaged but are still perfectly useable. In the Tektronix Service Center
we had an extra long power supply cable that made it much easier to turn the
555 on its side for maintenance. Let me know if you need some connectors to
make extenders.

You also asked me how many old scopes "blew up" :-) on turn on. No
explosions that I can recall, but some came quietly on but did not work
completely.

Stan

_____

From: TekScopes@yahoogrou <mailto:TekScopes%40yahoogroups.com> ps.com
[mailto:TekScopes@yahoogrou <mailto:TekScopes%40yahoogroups.com> ps.com] On
Behalf
Of faustian.spirit
Sent: Friday, December 29, 2006 6:38 PM
To: TekScopes@yahoogrou <mailto:TekScopes%40yahoogroups.com> ps.com
Subject: [TekScopes] Re: Bringing up a 555

--- In TekScopes@yahoogrou <mailto:TekScopes%40yahoogroups.com> ps.com,
"Stan and Patricia Griffiths"
<w7ni@...> wrote:

Hi Andy,



Others may call me careless in my approach to firing up an old 555,

but I

would just plug it in and turn it on. It is pretty well fused and I

would

not expect any to blow anyway.

Probably will soon... Visual inspection shows nothing suspicious at
least... I could put the L and CA in, but now I feel obliged to at
least try to recalibrate or fix the D (was marked "broken" but seems
to work except that the gain is too low and the CMRR is lousy... Most
of the switch trouble vanished after applying some Tuner 600) ...
whoever designed it had money in the plugin extender business I guess
:) And something with the idea of operating a 500 series lying on its
side strikes me as very odd... same with sawing a hole in the table...

Are the connectors needed to make an extender cable as rare as those
in the 551/555 PSU cable are said to be? I noted the pitch is
different....

You can not test the power supply disconnected from the scope and your
reason is correct. It must have a proper load on it and, yes, you

will need

all plugins in place to put a proper load on the power supply. Both
timebases and both verticals.



On old Tek scopes, I never bother to reform the electrolytics. A

shorted

one is very rare and an open one will show up as too much ripple

somewhere.

I have never seen a shorted one do serious damage.



Over the past 46 years, I have probably turned on more than 1000 of

these

old scopes. I have lost count but I have at least six or seven

555's in my

collection . . . maybe more.

How many blew up? :)

I think when originally shipped from the factory, the serial number

of the

power supply will match the serial number of the mainframe.

Sometimes in

the field, mainframes and power supplies get swapped around, but I can't
remember any serious incompatibility problems, even with mismatched

serial

numbers.



Stan

[Non-text portions of this message have been removed]

the arrl handbook is too basic for that.
i think the ee programs are more theoretical at an undergraduate level then they were 40 yrs ago
i have about 2 yrs of college but have never taken an "electronics" class.
they just taught me about "i" and how to integrate and differentiate
alot of advanced math is quite simple once you understand the concepts and models.
we live in a wonderful time where we can throw away our slide rules , log tables and hand held calcs
and let a computer crunch away on stuff for us.
many engineers designed complex stuff mostly using compiled tables and graphs
and then tweaking their designs until they worked "good enough"
thats what test equipment is used for in engineering.
to prove theoretical designs

Here are some measurements on my 494P. After about 3 hours of operation in its normal position (45 degrees tilted up on the handle, standing on the floor inside a wood rack without much air circulation), the hottest part of the metal case on the back panel was slightly over 60 degrees C. The hottest point is to the left of the instrument, when looking over the top standing in front of the instrument. On the right side, the temperature was about 5 degrees lower.

The winner is the HP 5370A, where the exposed rear heat sink reaches over 66 degrees C while the instrument is in open air. Ambient temperature in the shack was about 26 degrees C at the time these measurements were made.

In both cases, the line voltage was very close to 115 VAC (it fluctuates +/- a volt around 115 typically.)

Didier KO4BB


Gerald wrote:

The winner in my collection is the 517 at 1250 Watts.



Stan

Hi Andy,



You asked about connectors for extender cables. There are three possible
extenders you could be talking about: 1) vertical plugin, 2) timebase
plugin, 3) power cable from mainframe to power supply. I am sure I have
connectors that I can sell you to build extenders for either type of plugin
for a couple of dollars per connector. Most of what I have have been
salvaged but are still perfectly useable. In the Tektronix Service Center
we had an extra long power supply cable that made it much easier to turn the
555 on its side for maintenance. Let me know if you need some connectors to
make extenders.



You also asked me how many old scopes "blew up" :-) on turn on. No
explosions that I can recall, but some came quietly on but did not work
completely.



Stan



_____

From: TekScopes@... [mailto:TekScopes@...] On Behalf
Of faustian.spirit
Sent: Friday, December 29, 2006 6:38 PM
To: TekScopes@...
Subject: [TekScopes] Re: Bringing up a 555



--- In TekScopes@yahoogrou <mailto:TekScopes%40yahoogroups.com> ps.com,
"Stan and Patricia Griffiths"
<w7ni@...> wrote:

Hi Andy,



Others may call me careless in my approach to firing up an old 555,

but I

would just plug it in and turn it on. It is pretty well fused and I

would

not expect any to blow anyway.

Probably will soon... Visual inspection shows nothing suspicious at
least... I could put the L and CA in, but now I feel obliged to at
least try to recalibrate or fix the D (was marked "broken" but seems
to work except that the gain is too low and the CMRR is lousy... Most
of the switch trouble vanished after applying some Tuner 600) ...
whoever designed it had money in the plugin extender business I guess
:) And something with the idea of operating a 500 series lying on its
side strikes me as very odd... same with sawing a hole in the table...

Are the connectors needed to make an extender cable as rare as those
in the 551/555 PSU cable are said to be? I noted the pitch is
different....

You can not test the power supply disconnected from the scope and your
reason is correct. It must have a proper load on it and, yes, you

will need

all plugins in place to put a proper load on the power supply. Both
timebases and both verticals.



On old Tek scopes, I never bother to reform the electrolytics. A

shorted

one is very rare and an open one will show up as too much ripple

somewhere.

I have never seen a shorted one do serious damage.



Over the past 46 years, I have probably turned on more than 1000 of

these

old scopes. I have lost count but I have at least six or seven

555's in my

collection . . . maybe more.

How many blew up? :)

I think when originally shipped from the factory, the serial number

of the

power supply will match the serial number of the mainframe.

Sometimes in

the field, mainframes and power supplies get swapped around, but I can't
remember any serious incompatibility problems, even with mismatched

serial

numbers.



Stan

Hi, Gerald
Dont know in what part of Aussie you be, but over here in the West we are
often plagued with
higher than normal Line Voltages, specially if u live near an industrial
area
or near a feeder transformer / substation

No doubt u have already checked this , but just in case check yr own line
voltage
preferable with a true RMS meter or known caiibrated (standard AC) average
reading one
Test the line waveform too. Generally its a good enough sine wave but I
have seen
line waveform distortions in some of the places ive been that u woudn't
believe!

Check out that the 492P is on its max line taps (if it has such a selection)
and not
just on 220V.
Does it get so hot all the time, or only in the evenings? If the latter it
coulf be that
industrial area shut downs around knock off time leave an uncompensated line
voltage too high

For these very reasons my own GP bench in Perth is ran from a metered step
down auto transformer
with selectable taps and my test bench outlets from a number of AC
stabilizers to keep RMS
line volts to 220v with good AC waveform
If all this seems obvious and u are well aware of it all, my apologies, but
I have ran into
the same issue myself in the past and others with similar problems may
benefit

Whats the ambient temp in yr shop /room ? Probably an external fan is a good
idea anyway
in our ever warming climate for those items of lab gear really intended to
work
in a protected lab environment (not that ime saying the 492P is)

Of course,you could have a fault with the 492P that others are better
quailfied to comment
on but the above seems a good place to start.

Hope yr 492P gives u years of trouble free use. Happy new year

John (hpxref)

alot of modern equipment either just has a 115/230 vlt switch "like a pc" or a uni
versal input switching supply.
one simple solution for high line voltage is a filament transformer with n its secondary connected as a bucking winding
bucking down your high aussie voltage 25 vac down probably wont bother modern equipment
most modern equipment will work quite well on even 105 vac thats 210 vac on your settings
"experiment using a variac just be carefull about cranking the variac up very high on older equipment"
130 volts is plenty high for checking older stuff my variacs will put out almost 145vac with my high line voltage.
that could blow up and older piece of equipment.
some old radio buffs suggest using a bucking transformer inside of old radios to keep the input voltage down.
alot of very old stuff was designed to work on 110vac.
my 123 vac line voltage is a bit high.
look at the back of even a tek 547 "115 vac" i think the 547 has internal taps my 7904 just has the 115/230 vlt settings "switching supply

--- In TekScopes@..., Lars Ahlstr?m <lea56@...> wrote:

Yeah, I understand. Its just to accept.



But the whole brain of mine want to give the result [ sqrt(-1) = -

1 ]

!!! =)



If I draw a carthesian coordinate system and pinpoint X=1 and Y=1 I

get a

square of the sides = 1.

The square is 1. meter, mm, inch, foot or whatever

Your square of area=1 in the first quadrant of the XY plane, this is
correct.

And if I pinpoint X= -1 and Y= -1 I get a square with the sides -1,

and the

area is then -1. foot, inch, yard or whatever.

The area of the square in the third quadrant is area=1 as well.
Remember that Area = length * height for a square, that being Area = -
1 *-1 = 1, Area is not negative unless it is of a hole or empty space.

The root of -9 is -3 !!! (I think…;)

Almost. The root of -1 is "i" for math people, and is "j" for
electronics people.
i or j being root(-1)
i or j squared = -1,remember (root(-1))^2 the root and exponent cancel
i or j ^4th power = -1 *-1 = 1

you get the idea.

So, root(-9)= 3i or 3j for electronics people.

This ordinate in the complex plane is O= 0 + 3j, or simply 3 in the y
direction, and 0 in the x direction. There are lots of ways you can
play with this to give all kinds of phasors and vectors.



Matt

-----Ursprungligt meddelande-----
Fr?n: TekScopes@... [mailto:TekScopes@...]

F?r

arthurok
Skickat: den 30 december 2006 23:57
Till: tekscopes@...; Kuba Ober
?mne: Re: SV: [TekScopes] Invitation for another exchange of

questionably

useful information.



its a shared "delusion"
----- Original Message -----
From: Kuba Ober
To: tekscopes@yahoogrou <mailto:tekscopes%40yahoogroups.com> ps.com
Sent: Saturday, December 30, 2006 12:02 PM
Subject: Re: SV: [TekScopes] Invitation for another exchange of

questionably

useful information.

On Friday 29 December 2006 05:38, you wrote:

That post reminds me of my own high school drama: The j-omega

method.

The root of minus 1… still bugs me. Haven't yet figured it out

after 33

years...

For me it was too mind blowing. Had to stop thinking before I got

a

辫蝉测肠丑辞蝉颈蝉…



And… our teacher back then, was a well known idiot, that (by the

rumour)

got a anonymously job advertise in his mail for this teacher job

from a

former headmaster. He was totally incompetent as a mathematician

teacher,

and had one item in his track record only: as a mechanical

instrument tech

at ASEA. He was totally unable to give me the idea (part from my

own

brains

lack of fantasy) of the "root of minus one".

Well, it's an abstract concept, I guess it's better treated like

one. Your

only "idea" should be of the properties of this number, and some
applications
that suit your interests.

I don't think I have any other "ideas" here. You can go pretty far

by just

knowing that the number has "otherwise" normal properties, i.e. you

treat it

like any other number that only doesn't "mix" (in addition) with

real

numbers. And when you square it, it goes away. I did my grad level
vibrations
course without using any other "higher" properties (whatever those

might be)

of sqrt(-1). I guess it shows what a powerful concept it is: only

minimal

properties are necessary to extract a lot of mathematical

expression power.

Cheers, Kuba

Yeah, I understand. Its just to accept.



But the whole brain of mine want to give the result [ sqrt(-1) = -1 ]
!!! =)



If I draw a carthesian coordinate system and pinpoint X=1 and Y=1 I get a
square of the sides = 1.

The square is 1. meter, mm, inch, foot or whatever

And if I pinpoint X= -1 and Y= -1 I get a square with the sides -1, and the
area is then -1. foot, inch, yard or whatever.

The root of that square is -1 !!!

The root of -9 is -3 !!! (I think…;)



That’s why I cant accept it, I guess. I also see cube root of -1 = -1, no
problem! ;)



But Im just a fool…



/Lars







-----Ursprungligt meddelande-----
Fr?n: TekScopes@... [mailto:TekScopes@...] F?r
arthurok
Skickat: den 30 december 2006 23:57
Till: tekscopes@...; Kuba Ober
?mne: Re: SV: [TekScopes] Invitation for another exchange of questionably
useful information.



its a shared "delusion"

Reactance, Negative Frequency, Imaginary numbers, Inductance,
Capacitence, complex phasors, complex exponentials, Transform math...

If you have issues with these concepts then look at your options:
1. Become an EE student (I am one and it has done miracles for my
understanding of systems)
2. Get yourself a copy of the ARRL Handbook
3. Get copies of older electronics books
4. Read Wikipedia articles
5. Take an Applied Math class

It's all out there all you have to do is read.

What I don't understand is why my inbox gets filled up with sillyness
that EE students understand at a basic level.

P.S. If you don't believe in Negative Frequency, don't debate it with
me, just take a Communications Systems class or a DSP class and you
will see where the math and concepts are justified.

its a shared "delusion"

Looking for GAP/R (Philbrick) amplifiers might help. Some of those were
chopper-stabilized and used IIRC Airpax choppers.

Yes, I had though of that. I think, though, that I would be just as
guilty of a crime doing that as I would be taking the tubes out of an
early Tek scope to make an guitar amp. I think that if I got one of
those amplifiers, I'd have to build it a little shrine...

There's one in that auction place right now, too, taunting me.

This is not for filtering. The L manual says:

"Low-frequency peaking for the X10 amplifier is provided mainly by
C6002A and C6002B in the plate circuits of V5942 and V6042. With
their associated resistors, these capacitors form a low-frequency
boost network to compensate for the low-frequency attenuation
introduced in the cathode circuits, the screen circuits, and the RC
coupling network between the Second amplifier and the Second cathode
follower. ... the amount of attenuation can be varied with the LOW
FREQ. ADJ. control in the grid of V6132."

This technique is discussed in detail in "Typical Oscilloscope
Circuitry."

Larry Christopher





--- In TekScopes@..., "morriso2002" <vilgotch@...> wrote:

I'm not sure what you mean by the big honking filter cap in the L.

It

certainly has quite comprehensive decoupling of the B+ to the low
level amps which is pretty standard practice. I'm too lazy to get

out

my L to check, but that's almost certainly what it's for. That

quite

a high gain wideband amplifier and keeping such devices stable is

not

a trivial design task!

I have an invaluable book from Fairchild, published 1973. “The TTL
Application Hanbook”.



I checked your need, and what I can see, the only thing you need is a divide
by 10 counter.

The 8292 is very like the old 7490, today probably the 74LS90, in that it
can easily divide by 10.



The 7490 is two counters, one modulo 2 and one modulo 5. Together they
divide by 10.



You need to make a pin adapter.











In the pdf you need the LS90 B config, I guess, in order to get a
symmetrical output.



I hope this was a step in rite dir 4 u.



/Lars











-----Ursprungligt meddelande-----
Fr?n: TekScopes@... [mailto:TekScopes@...] F?r
arthurok
Skickat: den 30 december 2006 12:26
Till: TekScopes@...; Craig Sawyers
?mne: Re: [TekScopes] 7D15 COUNTER TIMER , FAULTY U688



maybe dean kidd has one