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Re: Kludging together a TDR or similar?

 

I threw one of these together a year or so ago- photo of internals here-

It works very well- considering how simple it is.
But an SMD version would be nice......
DaveB, NZ

-----Original Message-----
From: [email protected] [mailto:[email protected]] On Behalf Of Michael A. Terrell
Sent: Saturday, July 07, 2018 12:32
To: [email protected]
Subject: Re: [TekScopes] Kludging together a TDR or similar?

You can build a simple TDR with a 74AC14, some resistors and a couple capacitors.
<>

If that doesn't work, it is from this page:


It is sold on Ebay by <> It was $15.19 a couple months ago. It isn't available right now. I bought one, to test. If I like it I will make a surface mount version of it, and put it into a small extruded aluminum box. The box, and the three connectors will be about 80% of the component costs in a SMD version.



Michael A. Terrell


-----Original Message-----
From: cheater cheater <cheater00@...>
Sent: Jun 29, 2018 3:20 AM
To: [email protected]
Subject: Re: [TekScopes] Kludging together a TDR or similar?

hi guys, thanks for the replies.

I don't have the parts necessary to build a pulser. Can I use the
mainframe's pulse generator?

The cable goes from a local distribution box, part underground, part
overground, and then goes to a wall socket used only by my modem. There
is no splitting and no neighbors using this. The run in my yard that is
overground is maybe 30m at most.

There was no thunder when this stopped working, just heavy rain.
Re: Owon SDS7102 Deep Memory Digital Storage Oscilloscope

 

It was Episode one, of Season one. It was one of the very few Sci-Fi TV episodes that sucked me into the storyline. It first aired in 1963, and I was just 11 at the time. :)


Michael A. Terrell

-----Original Message-----
From: "Glydeck via Groups.Io" <glydeck@...>

I missed this one or don¡¯t remember it. Thanks for the link. My fav was ¡°Controlled Experiment¡± with Barry Morse and Carroll O¡¯Connor. I¡¯ll be enjoying ¡®Galaxy Being¡¯ tonight.
Re: Owon SDS7102 Deep Memory Digital Storage Oscilloscope

 

I missed this one or don¡¯t remember it. Thanks for the link. My fav was ¡°Controlled Experiment¡± with Barry Morse and Carroll O¡¯Connor. I¡¯ll be enjoying ¡®Galaxy Being¡¯ tonight.

George

On Jul 6, 2018, at 5:38 PM, Michael A. Terrell <mike.terrell@...> wrote:

That was 'The Outer Limits' and it ran all day on the 4th of July on Me TV. How many of you got into electronics after watching the 'Galaxy Being' episode? I know several AM radio engineers who claim that's what got them interested in Broadcast Engineering. :)

<>

You can download it for free here:

<>


Michael A. Terrell

-----Original Message-----
From: "vaclav_sal via Groups.Io" <vaclav_sal@...>

Do as old TV show did - YOU control the horizontal - time sweep and vertical - input scale.
Re: 114xx bezzel buttons

 

There's a link to the manuals on the TekWiki site:
Re: MEDIA MAIL (Re: [TekScopes] I have two Tek manuals I don't think I need)

 

This is a product of them being a FOR PROFIT business and nothing more. So many think they are a gov¡¯t entity

On Jul 6, 2018, at 7:21 PM, G Hopper <kb7wsd@...> wrote:

David, they absolutely don't want to offer it.

I just mailed a book (a user guide for a camera) to a friend. The counter
agent was funny. I handed the package over and said "it's a book and it
should go the cheapest way possible." I didn't mention "Media mail" mostly
as a test after seeing Dave's comment (I usually write media mail on the
package before I even go to the post office.)

The fellow tells me about the priority mail and First class prices.... I
smiled and said "wow, that's expensive for a book... (long pause) but I
didn't hear you mention a 'media mail' price?"
Him: "Oh, sorry, just one second, let me look that up for you" I could see
the screen in a reflection and the price was right there....
The cost was something like $3.17 (or less) instead of $11 to $17.

I get that they want to be as profitable as possible, but I think they need
to do that through efficiency and not by overcharging the customer and
directing them away from services that were designed just to benefit
certain kinds of mailings. They'd be far better off to charge a 1/10 cent
more for junk mail than push retail customers to high priced services that
make them choose UPS or some other service.

Grant

On Tue, Jul 3, 2018 at 11:05 AM, Vince A <vince83687@...> wrote:

David
You got to be vigilant at the PO, know before you go! Google and asking
questions here really helps you out. If it sounds fishy go back another day
or see another PO. Use a different guy/girl on another day at the PO.
Vince :)

---
-vince :")
Thank you for your reply
Got computer troubles, We have the answers!
Visit Starlite Systems
Starlitesystems Dot Com
My other computer cost's $35.00. Ask me about it

On Tue, Jul 3, 2018 at 9:13 AM, David Berlind <david@...> wrote:

So, just fyi.. I went back to the PO and asked "What about the media mail
option?" ... Bascially, it was "Oh, that? $3.17" (for what was
originally
$11.80). Pretty shocked that, like Dave says, they neglected to offer
that
option in the first place when I requested "least expensive shipping
option."

On Tue, Jun 26, 2018 at 2:38 PM, Artekmedia <manuals@...>
wrote:

They are trained NOT to tell you. You have to ASK for it or as the
previous poster said it is available through PayPal shipping includes
tracking. Tell them it just a "manuscript" and DO NOT INCLUDE any
correspondence. You put a one page letter in there and suddenly it is a
1st
class mail

For a description google is your friend

-DC
ArtekManuals.com

On 6/26/2018 1:40 PM, John Griessen wrote:

On 06/26/2018 11:26 AM, David Berlind wrote:

what is "media mail?" when I go to the post office, they offer me a
slew
of options.. but "media mail" is not one of them.
use paypal shipnow to get a label for media mail with a little extra
discount.




--
Dave
Manuals@...
www.ArtekManuals.com
Re: Owon SDS7102 Deep Memory Digital Storage Oscilloscope

 

YouTube

On Fri, Jul 6, 2018, 3:37 PM Vince A <vince83687@...> wrote:

Morning Gentleman

Well I finally bit the bullet and bought a 100mghz Scope. Now I need to
learn how to use it. :) Is there a oscilloscope for dummies book out there
or just some quick pointers you guys would like share with me? I am sure
a'll have a LOT of questions but I don't have a clue what to do next and
what all the fancy controls could or should do for me? I am mostly into
vacuum tube audio and some solid state electronics. The package did come
with some really nice probes and almost like a very small jewelers type of
screwdriver driver? And Manuel

What I would like to do first with this is to measure the Pre-amp signal of
the 12AT7 to see if i am getting a clean signal to the output of my first
pair of 6L6 tube amp I built using Russian output tubes. And if not, how
could I clean that up by doing other things to get the signal better though
the path? I don't learn very well by reading books guys, I am more of a
hands on guy. When I read books, the pages melt into each other after about
2 pages. So reading online is much better for me. That is why I like the
combined knowledge here.

How did you guys learn how to use a Scope? How did you go about getting
familiar with a Scope? What was your very first Scope? This is my VERY
first Scope of anything guys.
Thanks loads
Vince :)
---
-vince :")
Thank you for your reply
Got computer troubles, We have the answers!
Visit Starlite Systems
Starlitesystems Dot Com
My other computer cost's $35.00. Ask me about it
Re: Dead 7603

 

Uh, it would be nice if I could find where the caps on the +5V line are located! I don't see anything on the A11 Low Voltage Board schematic.

I assume the voltages from the LV board are distributed to most of the other boards, correct? Where should I look for failing power supply caps? (Or other suspects?)

Thanks.

Jim

------ Original Message ------
From: "Jim Ford" <james.ford@...>
To: [email protected]
Sent: 7/6/2018 4:47:30 PM
Subject: Re: [TekScopes] Dead 7603

Here's what the ripple voltages measured in volts peak to peak:

-50V: 20m
-15V: 20m
+5V: 3
+15V: 20m
+50V: 10m
+130V: 0.2

So, all out of spec except for +130V, and +5V way out. +5V was a high duty ratio waveform with little dropouts down to about 2V synchronous with the AC mains.

+5V rail caps to be checked next.

Jim

------ Original Message ------
From: "Jim Ford" <james.ford@...>
To: [email protected]
Sent: 7/6/2018 4:29:35 PM
Subject: Re: [TekScopes] Dead 7603

Thanks, everybody, for your help. Here's where I am now: Primary not
open; it measures about 3 ohms with the on/off switch on (obviously open
with it off!). Poked around P1171 and measured DC voltages. -50V,
-15V, +15V, +50V, and +130V all within spec. +5V measured 4.46 V, when
it's supposed to be 4.85V minimum. Hey, the power light is lit now!
Must have been a bad connection that I reconnected when moving the power
supply section back into place. Checking ripple and looking for shorted
tantalum capacitor(s) on the +5V rail next.

Jim

------ Original Message ------
From: "Vintage Test via Groups.Io" <mel.purcell@...>
To: [email protected]
Sent: 6/29/2018 7:31:36 AM
Subject: Re: [TekScopes] Dead 7603

Hi Jim,

On a 7603 - and I've sorted a lot of them - the main culprits of no
power-up, when you've checked all the usual suspects, is the power
supply filter capacitors. To check these, you will have to remove the
raw voltage power unit, situated at the bottom rear of the 'scope.
There are three large cross-head screws on each side of the chassis,
which allows you to carefully draw out the mains transformer and
attendant rectifier/capacitor PCB. If the capacitors are all metal
cased, it is likely that these are faulty now and need replaced.
Looking at the rear of the 'scope, there is a rectifier attached to the
bottom left corner , underneath the PCB. This is the +/- 15V rectifier
and the two caps nearest the left edge are the reservoirs. If these
don't have about 24V DC on them, then nothing else will work. Have a
look at this and get back to us.
--
you can never have enough oscilloscopes, DMMs, valve testers or
soldering irons . . .



---
This email has been checked for viruses by AVG.
Re: Owon SDS7102 Deep Memory Digital Storage Oscilloscope

 

That was 'The Outer Limits' and it ran all day on the 4th of July on Me TV. How many of you got into electronics after watching the 'Galaxy Being' episode? I know several AM radio engineers who claim that's what got them interested in Broadcast Engineering. :)

<>

You can download it for free here:

<>


Michael A. Terrell

-----Original Message-----
From: "vaclav_sal via Groups.Io" <vaclav_sal@...>

Do as old TV show did - YOU control the horizontal - time sweep and vertical - input scale.
Re: Kludging together a TDR or similar?

 

You can build a simple TDR with a 74AC14, some resistors and a couple capacitors.
<>

If that doesn't work, it is from this page:


It is sold on Ebay by <> It was $15.19 a couple months ago. It isn't available right now. I bought one, to test. If I like it I will make a surface mount version of it, and put it into a small extruded aluminum box. The box, and the three connectors will be about 80% of the component costs in a SMD version.



Michael A. Terrell

-----Original Message-----
From: cheater cheater <cheater00@...>
Sent: Jun 29, 2018 3:20 AM
To: [email protected]
Subject: Re: [TekScopes] Kludging together a TDR or similar?

hi guys, thanks for the replies.

I don't have the parts necessary to build a pulser. Can I use the
mainframe's pulse generator?

The cable goes from a local distribution box, part underground, part
overground, and then goes to a wall socket used only by my modem. There is
no splitting and no neighbors using this. The run in my yard that is
overground is maybe 30m at most.

There was no thunder when this stopped working, just heavy rain.
Re: Owon SDS7102 Deep Memory Digital Storage Oscilloscope

vaclav_sal
 

Do as old TV show did - YOU control the horizontal - time sweep and vertical - input scale.

Does the scope have "trace locator" button?
Use it to center a "point " on screen.

Does the cope has "calibration" output ?? Usually on back panel.
Usually 1kHz / +- x mV.

Set everything which has "automatic" to that.
Optionally - set the "input" to "ground" and move the trace to center of screen.
Inputs are usually "DC ground AC " coupled.Than select "DC" as input.

Hook your probe to calibration output and
adjust the "horizontal" to mS? range? ( 1kHz = 1mS ).

Adjust "vertical"? until you see " stripe " of trace.

Now set the vertical triggering? to manual and set trigger slope - to trigger on positive or negative edge of the calibration signal. Does not matter as long as the "trace " is steady.

Now you have a working scope triggered by a calibration signal.?

End of lesson 101

On Friday, July 6, 2018, 5:38:00 PM CDT, Vince A <vince83687@...> wrote:

Morning Gentleman

Well I finally bit the bullet and bought a 100mghz Scope. Now I need to
learn how to use it. :)? Is there a oscilloscope for dummies book out there
or just some quick pointers you guys would like share with me? I am sure
a'll have a LOT of questions but I don't have a clue what to do next and
what all the fancy controls could or should do for me? I am mostly into
vacuum tube audio and some solid state electronics. The package did come
with some really nice probes and almost like a very small jewelers type of
screwdriver driver? And Manuel

What I would like to do first with this is to measure the Pre-amp signal of
the 12AT7 to see if i am getting a clean signal to the output of my first
pair of 6L6 tube amp I built using Russian output tubes. And if not, how
could I clean that up by doing other things to get the signal better though
the path? I don't learn very well by reading books guys, I am more of a
hands on guy. When I read books, the pages melt into each other after about
2 pages. So reading online is much better for me. That is why I like the
combined knowledge here.

How did you guys learn how to use a Scope? How did you go about getting
familiar with a Scope?? What was your very first Scope? This is my VERY
first Scope of anything guys.
Thanks loads
Vince :)
---
-vince :")
Thank you for your reply
Got computer troubles, We have the answers!
Visit Starlite Systems
Starlitesystems Dot Com
My other computer cost's $35.00. Ask me about it
Re: TDS744

 

There's 4 or 5 TO-39 transistors on the CRT neck board. One of them is prone to shorting and causing that problem. Later revisions had a heatsink on it to keep it cooler.

Sometimes it will be discolored from thermal stress giving it away visually.

The TDS544A schematic with the early revision color CRT driver board is on Hakan's page; it may be of some help...

There's also a capacitor that often leaks and causes the same problem. Facing the front of the board, it is located on the left side/edge somewhat towards the rear - there's three in a row, and it's the largest of the three. 100uF 50V I believe. the leakage gets so bad that it begins conducting under the cap and starts burning the PCB due to carbonizing (sp?)

Jay
Re: Questions about TM mainframes with Option 2

 

On Thu, 05 Jul 2018 03:49:01 -0700, you wrote:

Hi all, first post here.

I'm looking to set up a TM 5000 series mainframe and trying to sort out the compatibility gotchas before I "pull the trigger" on one of these.

My main interest is in the differential amplifier plugins. I do mostly audio work and these are the ones I am thinking about:

5A13
5A19
5A20
5A21
5A22
5A26
ALL OF THE ABOVE GO INTO 5000 OSCILLOSCOPES AND DO NOT FIT INTO A
TM5000 mainframe.

AM502

Question #1) Will the AM502 work in a 5000 series mainframe? (there seems to be conflicting information about whether or not 500 series plugins work in 5000 series mainframes)
There's a compatibility list in the archives here. IIRC, the answer
is no.


Question #2) If I get a 5000 series mainframe with Option 2 (w/ the BNC connector panel on the back of the unit), would I be able to wire from an A5xx plugin's single ended output to a BNC connector on the back panel, and then connect this to a standard o-scope input?
I don't think so. Not sure what the BNC on the back is, but it's
likely an output. Your TM5000 plugins DO NOT EVER fit into a 5000
series scope mainframe THEY ONLY FIT INTO A TM5000 SERIES RACK.

The 5Axx and 5Bxx are vertical and horizontal plugins, which while
they LOOK as if they should plug into a TM5000 series rack, DO NOT.
AND in addition the DC5010, the DM5010, the PS 5010, etc TM5000 units
DO NOT plug into an oscilloscope frame.

Seriously. They have the same pitch (spacing) connectors, but there's
a very specific key (piece of plastic inbetween the connectors) that
is different so you CANNOT plug into the wrong frame. Just don't even
try.... The voltages are WAY different, for one.


My understanding is that Tek 5000 series scopes' baseline sensitivity is 10 mV/division, so I'm assuming I can set my scope to 10 mV/division, hook up the BNC out (wired to the A5xx plugin's output) from the back of the TM 5000 series mainframe and just plug it into my scope. Does this sound right?
I'd say that you'd have to see how the TM5000 is wired, have the
TM5000 plugin in the right slot (the back panel stuff is hard wired to
a particular slot if wired at all), and then see what the output is.
You're likely to be happier taking a front panel output over to the
scope. Reading manuals will give you the details (which I do not
know). Both of my 5000 series scopes need work, and the TM5000's I
have I don't think I bothered to use the BNC's on the rear. DOn't
have the AM503, anyway.


I really appreciate any advice you have about this.
You got it. Please pay particular attention to the capital letters
(yes, either shouting or used as emphasis), because I think the points
made are rather important. Never heard anyone manage to mix the two
series.

TM5000 was an upgrade to the TM500 series of plugin. Generally added
a microprocessor, an IEEE488 (HPIB) interface, local remote control of
the module and a relatively smart (pushbuttons not mechanical
switches) front panel interface.

Because of *some* similarities, the TM500 series of plugins (generally
older, no microprocessor, no remote, mechanical switches) *could* be
used in the TM5000 series frames, but there was never a remote
control.

The 5000 series of oscilloscope was a 1 mhz/50 mhz (varied) maximum
bandwidth oscilloscope intended as a lower cost option for mostly
medical electronics, unless you needed 50 mhz bandwidth (see the 54xx)
series and appropriate plugins).

Harvey
Re: Parting out 465 (not B) and a 464

 

The shaft size is 0.125 in or ~3.2mm. I didnt take the 368 back apart but
the one i cobbled together in it is the same I'm almost certain.

Sorry for the delay in responding. The small dish amplifiers i installed
for internet and cell phone here in my off the grid location are less than
reliable during monsoon season. Sometimes my replies can sit in my outbox
for 2 to 3 days. Still beats post.

Thanks again, Russ

On Friday, July 6, 2018, musicamex <musicamex@...> wrote:

Sorry, our internet has been dead . Let me measure and get back to you,
thanks, Russ

On Wednesday, July 4, 2018, Harvey White <madyn@...> wrote:

On Tue, 03 Jul 2018 22:46:01 -0700, you wrote:

Hi Keith,
If you have the extension shaft to pot couplers available, I'd be very
interested. They are the cast aluminum with plastic insert ones with 2 #4
set screws, like on the "var" knobs on the voltage combo controls. I have
2 that are broken that i cobbled together some Mexico style repairs on.
One with shrink tube because the plastic was broken, the other with a brass
standoff that i drilled and tapped. I could probably use a few other small
parts too. Like the cord wrap plastic tabs. I'll look up the proper names
if you want me to.

If they are the same as the ones in a 7A18, 7A26 and so on, I may have
some. What's the shaft diameter?

Harvey




Thanks, Russ





--
Good judgement comes from experience; experience comes from bad judgement.

99 times out of 10 a blown fuse is not due to a bad fuse.....
--
Good judgement comes from experience; experience comes from bad judgement.

99 times out of 10 a blown fuse is not due to a bad fuse.....
Re: Dead 7603

 

Here's what the ripple voltages measured in volts peak to peak:

-50V: 20m
-15V: 20m
+5V: 3
+15V: 20m
+50V: 10m
+130V: 0.2

So, all out of spec except for +130V, and +5V way out. +5V was a high duty ratio waveform with little dropouts down to about 2V synchronous with the AC mains.

+5V rail caps to be checked next.

Jim

------ Original Message ------
From: "Jim Ford" <james.ford@...>
To: [email protected]
Sent: 7/6/2018 4:29:35 PM
Subject: Re: [TekScopes] Dead 7603

Thanks, everybody, for your help. Here's where I am now: Primary not
open; it measures about 3 ohms with the on/off switch on (obviously open
with it off!). Poked around P1171 and measured DC voltages. -50V,
-15V, +15V, +50V, and +130V all within spec. +5V measured 4.46 V, when
it's supposed to be 4.85V minimum. Hey, the power light is lit now!
Must have been a bad connection that I reconnected when moving the power
supply section back into place. Checking ripple and looking for shorted
tantalum capacitor(s) on the +5V rail next.

Jim

------ Original Message ------
From: "Vintage Test via Groups.Io" <mel.purcell@...>
To: [email protected]
Sent: 6/29/2018 7:31:36 AM
Subject: Re: [TekScopes] Dead 7603

Hi Jim,

On a 7603 - and I've sorted a lot of them - the main culprits of no
power-up, when you've checked all the usual suspects, is the power
supply filter capacitors. To check these, you will have to remove the
raw voltage power unit, situated at the bottom rear of the 'scope.
There are three large cross-head screws on each side of the chassis,
which allows you to carefully draw out the mains transformer and
attendant rectifier/capacitor PCB. If the capacitors are all metal
cased, it is likely that these are faulty now and need replaced.
Looking at the rear of the 'scope, there is a rectifier attached to the
bottom left corner , underneath the PCB. This is the +/- 15V rectifier
and the two caps nearest the left edge are the reservoirs. If these
don't have about 24V DC on them, then nothing else will work. Have a
look at this and get back to us.
--
you can never have enough oscilloscopes, DMMs, valve testers or
soldering irons . . .



---
This email has been checked for viruses by AVG.
Re: Owon SDS7102 Deep Memory Digital Storage Oscilloscope

 

On Fri, 29 Jun 2018 08:59:08 -0600, you wrote:

Morning Gentleman

Well I finally bit the bullet and bought a 100mghz Scope. Now I need to
learn how to use it. :) Is there a oscilloscope for dummies book out there
or just some quick pointers you guys would like share with me? I am sure
a'll have a LOT of questions but I don't have a clue what to do next and
what all the fancy controls could or should do for me? I am mostly into
vacuum tube audio and some solid state electronics. The package did come
with some really nice probes and almost like a very small jewelers type of
screwdriver driver? And Manuel
Sounds like you have enough scope for the moment. You should use the
probes.

You have an electrical graph. The Y axis (vertical) is almost always
the voltage. The X axis (horizontal) is almost always the time. When
you see a sine wave signal, the Y is the amplitude, and the X is time.



What I would like to do first with this is to measure the Pre-amp signal of
the 12AT7 to see if i am getting a clean signal to the output of my first
pair of 6L6 tube amp I built using Russian output tubes.
Look at this first. You might know what the input frequency is.
That'll help.

You hook up the probe to the channel 1 input, and select channel 1
(you *do* have to read the instructions). Connect the probe to the
point you want to measure. Select AC input to start with. (not DC or
Ground).


adjust the vertical gain until the signal is not off the screen.
Ideally, it should be within the graticule limits.

Select trigger to be internal (the signal you're watching, and channel
1 if needed), select the A timebase to be on and not use the B
timebase. (read the manual again, it's the most basic setup)

adjust the A timebase control to get one or two sine waves on the
screen. The trigger adjustment will stabilize this. Again, you just
*have* to read the manual.

Now that you have the output of the stage (or input) selected. Look
for obvious distortion. Please note that the oscilloscope is good for
obvious stuff, but not for the really fine measurements of distortion.

Follow the signal through the amplifier by moving the probe's
attachment to the amplifier. Adjust the gain control as needed. Note
that the signal does not change frequency, so once the timebase is set
up, you need not change that.


And if not, how
could I clean that up by doing other things to get the signal better though
the path?
This I cannot tell you. It has much to do with the design of the
amplifier, the tubes involved, and where the bias points are (please
google class A (the first ones) and Class B (likely the output stages)
amplifiers.



I don't learn very well by reading books guys, I am more of a
hands on guy. When I read books, the pages melt into each other after about
2 pages.
So reading online is much better for me. That is why I like the
combined knowledge here.
Reading online is still reading. People won't necessarily type more
than two pages. When reading, stop after two pages, review when
needed, take a break, and then continue.


How did you guys learn how to use a Scope?
Sine waves, signal generators, looking at waveforms I thought I
understood. Experimenting playing with the settings. Making
mistakes.

How did you go about getting
familiar with a Scope?
I played with it. I read the manual. In this particular case, I
actually built it.

What was your very first Scope? This is my VERY
first Scope of anything guys.
Heathkit OM-3. Tubes, very much low end compared to scopes now.
Limited bandwidth (VERY!!!), design flaws (had to run the tubes off DC
for the filaments, seriously, AC hum from the heater circuits was
horrible, and this was not part of the original design).

Bottom line:

1) experiment
2) look at known waveforms
3) a function generator (or signal generator) is your best friend.
4) right before that, put the manual.
5) for tektronix scopes, tektronix put out a series of "how to" and
"theory" manuals that are very useful, but at a higher level than you
want (goes into circuit theory). You want to skim them for the "do
this" part of the book. Same stuff ought to be in the
operational/user manual for your scope.
6) keep asking questions

Harvey

Thanks loads
Vince :)
---
-vince :")
Thank you for your reply
Got computer troubles, We have the answers!
Visit Starlite Systems
Starlitesystems Dot Com
My other computer cost's $35.00. Ask me about it
Parting out 465 (not B) and a 464

 

Sorry, our internet has been dead . Let me measure and get back to you,
thanks, Russ

On Wednesday, July 4, 2018, Harvey White <madyn@...> wrote:

On Tue, 03 Jul 2018 22:46:01 -0700, you wrote:

Hi Keith,
If you have the extension shaft to pot couplers available, I'd be very
interested. They are the cast aluminum with plastic insert ones with 2 #4
set screws, like on the "var" knobs on the voltage combo controls. I have
2 that are broken that i cobbled together some Mexico style repairs on.
One with shrink tube because the plastic was broken, the other with a brass
standoff that i drilled and tapped. I could probably use a few other small
parts too. Like the cord wrap plastic tabs. I'll look up the proper names
if you want me to.

If they are the same as the ones in a 7A18, 7A26 and so on, I may have
some. What's the shaft diameter?

Harvey




Thanks, Russ





--
Good judgement comes from experience; experience comes from bad judgement.

99 times out of 10 a blown fuse is not due to a bad fuse.....
Re: Parting out 465 (not B) and a 464

 

Sorry, our internet has been dead . Let me measure and get back. Thank
you, Russ

On Wednesday, July 4, 2018, Harvey White <madyn@...> wrote:

On Tue, 03 Jul 2018 22:46:01 -0700, you wrote:

Hi Keith,
If you have the extension shaft to pot couplers available, I'd be very
interested. They are the cast aluminum with plastic insert ones with 2 #4
set screws, like on the "var" knobs on the voltage combo controls. I have
2 that are broken that i cobbled together some Mexico style repairs on.
One with shrink tube because the plastic was broken, the other with a brass
standoff that i drilled and tapped. I could probably use a few other small
parts too. Like the cord wrap plastic tabs. I'll look up the proper names
if you want me to.

If they are the same as the ones in a 7A18, 7A26 and so on, I may have
some. What's the shaft diameter?

Harvey




Thanks, Russ





--
Good judgement comes from experience; experience comes from bad judgement.

99 times out of 10 a blown fuse is not due to a bad fuse.....
Re: Dead 7603

 

Thanks, everybody, for your help. Here's where I am now: Primary not
open; it measures about 3 ohms with the on/off switch on (obviously open
with it off!). Poked around P1171 and measured DC voltages. -50V,
-15V, +15V, +50V, and +130V all within spec. +5V measured 4.46 V, when
it's supposed to be 4.85V minimum. Hey, the power light is lit now!
Must have been a bad connection that I reconnected when moving the power
supply section back into place. Checking ripple and looking for shorted
tantalum capacitor(s) on the +5V rail next.

Jim

------ Original Message ------
From: "Vintage Test via Groups.Io" <mel.purcell@...>
To: [email protected]
Sent: 6/29/2018 7:31:36 AM
Subject: Re: [TekScopes] Dead 7603

Hi Jim,

On a 7603 - and I've sorted a lot of them - the main culprits of no
power-up, when you've checked all the usual suspects, is the power
supply filter capacitors. To check these, you will have to remove the
raw voltage power unit, situated at the bottom rear of the 'scope.
There are three large cross-head screws on each side of the chassis,
which allows you to carefully draw out the mains transformer and
attendant rectifier/capacitor PCB. If the capacitors are all metal
cased, it is likely that these are faulty now and need replaced.
Looking at the rear of the 'scope, there is a rectifier attached to the
bottom left corner , underneath the PCB. This is the +/- 15V rectifier
and the two caps nearest the left edge are the reservoirs. If these
don't have about 24V DC on them, then nothing else will work. Have a
look at this and get back to us.
--
you can never have enough oscilloscopes, DMMs, valve testers or
soldering irons . . .



---
This email has been checked for viruses by AVG.
Re: MEDIA MAIL (Re: [TekScopes] I have two Tek manuals I don't think I need)

 

David, they absolutely don't want to offer it.

I just mailed a book (a user guide for a camera) to a friend. The counter
agent was funny. I handed the package over and said "it's a book and it
should go the cheapest way possible." I didn't mention "Media mail" mostly
as a test after seeing Dave's comment (I usually write media mail on the
package before I even go to the post office.)

The fellow tells me about the priority mail and First class prices.... I
smiled and said "wow, that's expensive for a book... (long pause) but I
didn't hear you mention a 'media mail' price?"
Him: "Oh, sorry, just one second, let me look that up for you" I could see
the screen in a reflection and the price was right there....
The cost was something like $3.17 (or less) instead of $11 to $17.

I get that they want to be as profitable as possible, but I think they need
to do that through efficiency and not by overcharging the customer and
directing them away from services that were designed just to benefit
certain kinds of mailings. They'd be far better off to charge a 1/10 cent
more for junk mail than push retail customers to high priced services that
make them choose UPS or some other service.

Grant

On Tue, Jul 3, 2018 at 11:05 AM, Vince A <vince83687@...> wrote:

David
You got to be vigilant at the PO, know before you go! Google and asking
questions here really helps you out. If it sounds fishy go back another day
or see another PO. Use a different guy/girl on another day at the PO.
Vince :)

---
-vince :")
Thank you for your reply
Got computer troubles, We have the answers!
Visit Starlite Systems
Starlitesystems Dot Com
My other computer cost's $35.00. Ask me about it

On Tue, Jul 3, 2018 at 9:13 AM, David Berlind <david@...> wrote:

So, just fyi.. I went back to the PO and asked "What about the media mail
option?" ... Bascially, it was "Oh, that? $3.17" (for what was
originally
$11.80). Pretty shocked that, like Dave says, they neglected to offer
that
option in the first place when I requested "least expensive shipping
option."

On Tue, Jun 26, 2018 at 2:38 PM, Artekmedia <manuals@...>
wrote:

They are trained NOT to tell you. You have to ASK for it or as the
previous poster said it is available through PayPal shipping includes
tracking. Tell them it just a "manuscript" and DO NOT INCLUDE any
correspondence. You put a one page letter in there and suddenly it is a
1st
class mail

For a description google is your friend

-DC
ArtekManuals.com

On 6/26/2018 1:40 PM, John Griessen wrote:

On 06/26/2018 11:26 AM, David Berlind wrote:

what is "media mail?" when I go to the post office, they offer me a
slew
of options.. but "media mail" is not one of them.
use paypal shipnow to get a label for media mail with a little extra
discount.




--
Dave
Manuals@...
www.ArtekManuals.com
Re: SC504 Gain Knob Removal

tom jobe
 

Hi Larry,
Your question got me wondering about this, so I took the side cover off of an SC504 to have a look.
The service manual mechanical parts diagram shows the knob has a longer part that goes back into the Channel switch so I looked to see if there was a screw or other fastening device back inside of the scope. I removed the plastic rod that goes through the knob assembly by disconnecting it at the aluminum collar on the VAR switch, and then the knob just fell out for some reason. I put the knob back in and then it would not come out again. So I nervously pried and pulled and got it back out again without damaging it.
A study of the knob shaft showed no locking mechanisms of any kind, so I rubbed a very thin smear of Johnson's paste wax on the knob shaft extension and put it back in. After that the knob slid in and out nicely and the only thing holding the knob in is the 1/8" fiberglass VAR shaft and small VAR knob in the center of the knob in question.
I guess the knob was just stuck from being in there for 30 or 40 years plastic on plastic?
Do be careful about a very thin aluminum washer that is on the knob's rear shaft extension, as it would be very easy to drop that washer into the scope. My guess is that this washer is part of the spacing arrangement that keeps the lettering on the back side of the knob skirt from hitting the front panel and getting damaged, and it also might keep the two plastic parts from rubbing on each other at the knob extension / attenuator surfaces?
tom jobe...
PS I wonder if one drop of water could be put in from the side where the knob shaft extension goes into the attenuator assembly to break it free as you wiggled the knob to spread it around? You would want to be very careful about anything you put in there, as the short and long term effects on the plastic parts could be devastating.

On 7/6/2018 11:30 AM, Larry McDavid wrote:
I have a SC504 scope module with a damaged Channel 1 knob skirt and I have a Tek replacement skirted knob. I can remove the small red central knob by loosening a set screw.

How is the skirted knob removed? I've tried gently pulling on it without success. The knob has a long plastic shaft with some internal ribs to fit over another shaft but I don't know how the knob is attached.

Anyone done this?
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