Date   
Re: 11801 software error

 

Sounds great Jerry. You need to have backup power on the two Rams on the Timing board (the two in socketed backup sockets). The scope needs to go through at least two power cycles once the new rams are installed.

If I remember right, the calibration signal needs to be turned on in one of the menus.

Also, the SD-24 will generate its own fast rise pulse when you enable TDR mode. It is quite an interesting plug in.

Regards

On 6/2/2019 12:57 PM, Jerry wrote:
Tom, thanks.
Yes, the SD-24 works from what I can tell. I'm able to scope the internal clock signal that is present as a front panel port. I can't get anything but noise out of the calibration port. I'm going to try an external trigger input using the internal clock output, scope the calibrator, and see if it is a timing problem. I read where the calibrator is synced to that signal and maybe delayed. I saw something also that only certain modules can be calibrated so I don't know if the calibrator is turned on if the correct module isn't installed.

But I have to get these software errors corrected or at least figure out where they are coming from. It acts like a slowly failing rom chip so maybe if I just download the code and load it into a new chip the problem will go away. It could also be glitching due to the power switch being twisted together but I have the power switch fixed now so I will install it and try again.

Thanks for the input. All hints appreciated.

Jerry


Re: 11801 software error

Bob Koller
 

The factory diagnostics manual in available on the KO4BB site, just search for the 11801. It may help with the error message.
The easiest way to get a valid race to start with, make the necessary connections , from the soft menu INITIALIZE, then AUTOSET. But, you may then have to go to the Trigger menu and reset the Source to Internal Clock if you want to use the calibrator. Autoset again.
Or, if using external source, either use a SMA power divider to provide a signal to the External Sync, or if the source has a suitable sync signal
Always be aware of the signal levels!

Re: Clock error on TDS3034

Heinz Breuer
 

Von meinem iPhone gesendet

Re: Weird(?) behaviour in tek 492BP power distribution - Please help

 

Thank you Karin,
I will check it carefully and come back with the results.
Roger

Re: 11801 software error

Jerry
 

Interesting pointer about the clock disappearing but I can see it if I set the scope to internal and scope the clock output. So it looks like everything is working but something is heating up and causing this error (hangs the machine);

INTERNAL SOFTWARE ERROR - CYLCE POWER OFF/ON
Report this information to field service:
F038 0110 F108 2A06 F967 0022 F7DY 80AF 0006
8030 2A16 0000 F7D7 8000 0001 1130 1130 2A0A

and at that point it hangs. Power off and on might get a few more minutes of operation and then it will shutdown with that error.

I have the diagnostics bypassed and I assume if I run them I will see the failing unit. I tried clearing NVRAM by holding Waveform and Trigger, I think it was, but no luck. So I think there is something heating up. Also, I don't see anything like this in the manual. But thanks for suggesting I look there.

This sort of sucks because it is close. It will run for about 10 minutes or so before this takes over.f

Jerry

EZ Test for 4041

Gary Robert Bosworth
 

Does anyone have a DC-100A tape with Tektronix EZ-TEST software on it for the Tektronix 4041 GPIB Controller, that they are interested in selling? Mine has become weak with time and is not reliable anymore.
Gary

Re: 11801 software error

Reginald Beardsley
 

The 11801 is just enough different from the 11801A/B/C that you need to have the 11801 manual and not one of the others. Zenith scanned the manual and sent me a copy. I think it's been sent to BAMA, etc, but not sure if it's posted yet. Email me if you don't find the correct manual.

The calibrator is only turned on when the triggering is set to internal. And the clock out is also only enabled when set to internal triggering. The INITIALIZE command resets the triggering to external. The software is *very* buggy. Certain operations will result in spurious trace artifacts and a ~10x timebase error which is *only* fixed by INITIALIZE as far as I can tell.

Reg

Re: 11801 software error

 

On Mon, Jun 3, 2019 at 03:45 PM, Reginald Beardsley wrote:


I think it's been sent to BAMA,
It's on TekWiki

/Håkan

Re: 7B92A time-base plug-in odd behaviour

Colin Herbert
 

Hi,
In continuation of this, when the scope is turned on and the CRT has warmed up, all I see is a vertical line (or a spot) on the left of the screen, corresponding to the Y input. The "TRIG'D" light is illuminated, but there is no horizontal sweep. If I pull out the "TIME/DIV" knob to show the "ALT" time-base display, I get a sweep but this is not altered by the "TIME/DIV" knob, but _is_ altered by the transparent skirt. Again, the "TRIG'D" light is illuminated. After some warm-up period, a horizontal sweep with the "TIME/DIV" knobs locked can be seen, but it is unstable and doesn't always travel the entire width of the display. What _does_ sometimes have an effect on the horizontal sweep is the "VARIABLE" knob, but this also alters the width of the sweep; is this supposed to happen? If I use "NORM" triggering mode with no Y input, the sweep is blanked as you would expect.
I realise that there are jumpers on the boards to alter the "TIME/DIV" selector from delaying sweep to delayed sweep and for compatibility with different mainframes. As far as I can tell, these are set for variable delaying sweep and for 7400, 7600 and 7700 mainframes (mine is a 7623A). I am wondering if S800 has a problem (it is difficult to access without removing a few things, or if the switch associated with the "VARIABLE" knob is faulty. I have ascertained that switch S490 is _not_ causing any of these problems (by wiggling it when the time-base is connected using a rigid extender - the time-base doesn't seem to work with either of my flexible extenders and I'm sure that they're good) .
I am also thinking that the time-base cam switches might benefit from cleaning, but as I said before, there are around 50 of them and that sounds like a big job, unless someone can tell me where I might try first.
I have cleaned the PCB edge-contacts which connect to the mainframe with no improvement (although some blue stuff came off some of the contacts) and I have tried another time-base plug-in (my 7B53A) which works fine.
Head-scratching time....

TIA, Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Albert Otten
Sent: 30 May 2019 19:34
To: TekScopes@groups.io
Subject: Re: [TekScopes] 7B92A time-base plug-in odd behaviour

Hi Colin,

When the sweep stops I would expect a blanked screen. You still see the signal at the start position of the sweep. This could perhaps mean that the sweep is running but that the sweep output to the horizontal amplifier is interrupted.
Is the screen blanked when you don't trigger the sweep(s)?
Perhaps you should choose the lowest possible sweep rate. If you then wiggle the time/knob and the sweep reappears, does it start then at the left side or does it start "random" at some horizontal position, as if the sweep was running normally but with sweep output interrupted? Maybe you can also recognize a still normally running sweep from the trigger light blinking.
(Just an idea. I have not encountered this problem.)

Albert



On Thu, May 30, 2019 at 07:01 PM, Colin Herbert wrote:


Has no-one any ideas about this? Surely it can't be that unusual a problem?
Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Colin
Herbert via Groups.Io
Sent: 24 May 2019 16:49
To: TekScopes@groups.io
Subject: Re: [TekScopes] 7B92A time-base plug-in odd behaviour

Not totally the case, Albert. As I said, the instability can be present after
warm-up and can be stopped or induced by "wiggling" the Time/Div knob.
Specifically, if the delaying or delayed time-base is showing (i.e. the
Time/Div knob is "IN") and the Time/Div knob is pushed in a little more
firmly, the time-base stops and a vertical line or dot (depending on the Y
input) at the left-hand side is shown.

Yes, It is the model with the "Alt Off" position on the Trace Sep knob; the
S/N is B096566.

Colin.


Re: 453 HV Transformer Rewind SUCCESS

Dave Wise
 

[SUPPLEMENT 5 omitted because...]

SUPPLEMENT 6 2019-05-31

John Sykes unwound his transformer
and got the following turns counts which are accurate +/- 1 turn:

5-9-7 0T-543T-1101T
6-10 0T-583T

Reminder: I wound a layer, then a (insulated) retrace to the starting side, then the next layer, instead of winding back and forth. This reduces the winding capacitance, which reduces loss.

Re: 7B92A time-base plug-in odd behaviour

Albert Otten
 

Hi Colin,

I hardly use my 7B92A and I had to play with it some time to re-familiarize myself with how it operates. That must be difficult when the 7B92A is faulty and new to you. Here are some "features" that might or might not help you.
- In Normal sweep mode (locked knobs) the displayed sweep actually is generated as delayed sweep, not as delaying sweep.
- The upper readout is for the delaying sweep, the lower readout is for the delayed sweep. Note how the readout jumps from lower to upper when from Normal sweep you pull the Time/Div knob.
- The delaying sweep goes up to 10 ns/div even when the knob is at a faster position. (Just try the previous remark at 1 ns/div).
- I have VAR set for Delayed sweep. So VAR also affets the sweep rate in Normal sweep mode. VAR can reduce sweep speed and at the same time reduces sweep length (like you seemed to notice).
- ALT mode is set by pulling the Time/Div knob *and* setting Trace Sep not fully ccw. Is that wheat you meant by ALT? Then 2 traces are displayed. The upper (delaying, with intensified zone) trace intensity is controlled by the 7B92A Intensity(!) and probably invisible when you set that Intensity fully ccw previously. The lower (delayed) trace listens to the mainframe Intensity.
- If you turn the transparent skirt in ALT mode then you change the delaying time/div. This will shift the delayed t race (unless Delay Time Multiplier is fully ccw). Is that what you observed?
- The trigger light is on during the delayed sweep (in Normal sweep mode) or during the delaying sweep mode (in all not-Normal modes). This can easily be recognized at a very slow time/div and even slower trigger signal.

Altogether I have the impression the your delaying sweep is working and displayed in non-Normal modes but that the delayed sweep is interrupted somewhere. I guess that the delayed sweep generator itself is working correctly since otherwise triggering would be blocked I think. It's difficult to follow in the schematics when triggering is blocked and given free again. The same holds for (un)blanking signals.

Albert

On Mon, Jun 3, 2019 at 06:42 PM, Colin Herbert wrote:


Hi,
In continuation of this, when the scope is turned on and the CRT has warmed
up, all I see is a vertical line (or a spot) on the left of the screen,
corresponding to the Y input. The "TRIG'D" light is illuminated, but there is
no horizontal sweep. If I pull out the "TIME/DIV" knob to show the "ALT"
time-base display, I get a sweep but this is not altered by the "TIME/DIV"
knob, but _is_ altered by the transparent skirt. Again, the "TRIG'D" light is
illuminated. After some warm-up period, a horizontal sweep with the "TIME/DIV"
knobs locked can be seen, but it is unstable and doesn't always travel the
entire width of the display. What _does_ sometimes have an effect on the
horizontal sweep is the "VARIABLE" knob, but this also alters the width of the
sweep; is this supposed to happen? If I use "NORM" triggering mode with no Y
input, the sweep is blanked as you would expect.
I realise that there are jumpers on the boards to alter the "TIME/DIV"
selector from delaying sweep to delayed sweep and for compatibility with
different mainframes. As far as I can tell, these are set for variable
delaying sweep and for 7400, 7600 and 7700 mainframes (mine is a 7623A). I am
wondering if S800 has a problem (it is difficult to access without removing a
few things, or if the switch associated with the "VARIABLE" knob is faulty. I
have ascertained that switch S490 is _not_ causing any of these problems (by
wiggling it when the time-base is connected using a rigid extender - the
time-base doesn't seem to work with either of my flexible extenders and I'm
sure that they're good) .
I am also thinking that the time-base cam switches might benefit from
cleaning, but as I said before, there are around 50 of them and that sounds
like a big job, unless someone can tell me where I might try first.
I have cleaned the PCB edge-contacts which connect to the mainframe with no
improvement (although some blue stuff came off some of the contacts) and I
have tried another time-base plug-in (my 7B53A) which works fine.
Head-scratching time....

TIA, Colin.

Re: Weird(?) behaviour in tek 492BP power distribution - Please help

d.schilling.net@...
 

Just an observation: It seemed to work until you worked on the front panel.
-David

Re: Chassis for free

 

Hi David,
I have one. It is obviously going to be a different date code but that is not important
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of David Berlind
Sent: Thursday, May 30, 2019 3:22 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Chassis for free

Before these go into the trash heap, I am looking for a chip that goes into the PCB at the back of slot 1 on a 7603 chassis with the marking:

155 0022 00
733 542 USA

I would greatly appreciate it if anyone is willing to spare that chip.

Thank you!



--
Dennis Tillman W7PF
TekScopes Moderator

Re: 7A13 relay substitution report

 

Hi Fabio and Tom,
Tek made relays are notoriously bad. This is because the "expert" Tek hired to design, manage, and produce them was not an expert after all.

I have experienced the exact same thing you did with the rotors on your 7A13 trim capacitors on one of my 7A22 plugins. The rotors just fall out of the variable capacitors without any apparent explanation. More than half the rotors fell out of one 7A22 I owned. I was stunned to see something like this happening so quickly that I couldn’t pick up the pieces fast enough. It was very strange how it happened to so many capacitors almost all at once. I don't think Tek made these capacitors however.

Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of tomford717@...
Sent: Saturday, June 01, 2019 8:18 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] 7A13 relay substitution report

Hi Fabio,

I'm going through the same 7A13 repair as you are. My Tek relays are failing and three rotors have fallen out of the air-variable input tuning caps.

I chose the Fujitsu NA12W-K as my replacement relay and decided to replace them all. The Fujitsu is rated at 220 VDC and has good specs at 100MHz. I made a pcb adapter board to simplify the wiring. Only two different pcb patterns were needed to satisfy all of the Tek relay pin-outs.

I included an SMT full wave bridge on the pcb to convert the Fujitsu relays to non-polarity coil types. I've replaced all relays and the four input attenuator variable caps. The DC offset and gain calibration has gone well. I am partially done with the RF cal and so far, the 3dB BW has been good to 100MHz using a 50 Ohm source.

My concern now is BW performance when the input attenuators are in operation. I have taken capacitance measurements of the Tek, Fujitsu, and Omron G6K relays. They all measure about the same when separate. When I mount the Fujitsu relay to the adapter board, the capacitance between the armature to the open contact jumps from 0.3pF to about 1.7pF. The pcb adapter adds roughly 1.3pF to all four inter-electrode points I've measured. I'm using a DE-5000 LCR meter @100KHz. I have pics of my progress so far if anyone has an interest.

Thanks,
Tom Ford




--
Dennis Tillman W7PF
TekScopes Moderator

Re: Chassis for free

Dave Seiter
 

Hi Dennis,
I already sent David a chip.
-Dave

On Monday, June 3, 2019, 10:00:54 PM PDT, Dennis Tillman W7PF <@Dennis_Tillman_W7PF> wrote:

Hi David,
I have one. It is obviously going to be a different date code but that is not important
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of David Berlind
Sent: Thursday, May 30, 2019 3:22 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Chassis for free

Before these go into the trash heap, I am looking for a chip that goes into the PCB at the back of slot 1 on a 7603 chassis with the marking:

155 0022 00
733 542 USA

I would greatly appreciate it if anyone is willing to spare that chip.

Thank you!



--
Dennis Tillman W7PF
TekScopes Moderator

Re: 7A13 relay substitution report

Craig Sawyers
 

Hi Fabio and Tom,
Tek made relays are notoriously bad. This is because the "expert" Tek hired to design, manage, and
produce them was not an expert after all.
Dennis Tillman W7PF
That is very interesting Dennis, and is information I did not know about those relays.

Personally I have only had one fail totally as a result of an O/C coil - a particularly small one in
a 7A11 probe head. But fortunately that was when Deane Kidd was alive and active, and of course he had
one in his basement trove.

The dreaded contact problem can only be properly cured by carefully dremelling off the lid along the
plastic weld line, clean the contacts with alcohol and paper, and then either reattach the lid or just
leave it off entirely.

Craig

Re: Chassis for free

David Berlind
 

Yes! Thank you David and Dennis for stepping up with offers to help! I'm
very much looking forward to dropping that chip into my 7603. I'll let
you know how it works out.

On Tue, Jun 4, 2019 at 3:33 AM Dave Seiter <d.seiter@...> wrote:

Hi Dennis,
I already sent David a chip.
-Dave
On Monday, June 3, 2019, 10:00:54 PM PDT, Dennis Tillman W7PF <
@Dennis_Tillman_W7PF> wrote:

Hi David,
I have one. It is obviously going to be a different date code but that is
not important
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of David
Berlind
Sent: Thursday, May 30, 2019 3:22 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Chassis for free

Before these go into the trash heap, I am looking for a chip that goes
into the PCB at the back of slot 1 on a 7603 chassis with the marking:

155 0022 00
733 542 USA

I would greatly appreciate it if anyone is willing to spare that chip.

Thank you!



--
Dennis Tillman W7PF
TekScopes Moderator






Back cover 2445a

Fred Schumacher
 

Hi All,
To finish my 2445a, I am looking for a back cover, including the two feet and associated screws.
Maybe there is somebody out there in europe, as I am living in the Netherlands, having a scrap 2445a with these parts in good shape. Let me know.
Thanks in advance,
Fred Schumacher

What is the fairest way to distribute scarce Tek resources

 

Often when a member says they have some Tek scope/instrument/plugin/part/etc
that they no longer need or want the next person who happens to logon is the
lucky individual who grabs it.

On occasion I have been the first to reply and benefited from this. More
often than not I see the email long after the item has been spoken for.

This happens often enough to all of us that we would benefit from finding an
alternative way to share our combined resources.



I would like suggestions on what is a fairer way to distribute Tek related
things to TekScopes members.

This affects all of us. It should not depend on chance.



Dennis Tillman W7PF

How can we set up a Parts Wanted list on Groups.io

 

At the Seaside OR ham swap meet last Saturday one of the TekScopes members
asked if there was a way to list some Tek parts he was looking for on
TekScopes.

Of course there really isn't one at the moment but if we could set one up
what would it look like and how would it work?

If we can work out something "simple" maybe we can get Groups.io to
implement it for us.



Does anyone know how other groups handle this?



Dennis Tillman W7PF