what's up mark? I have an sc504 that i had problem with.
mine turned out to be the hv multiplier.
jim

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OK that some sense , although I doubt it is a "bare" board, I suspect the parts in the kit are external to the board, and that the board is otherwise fully assembled


Dave





On 7/16/2012 8:24 AM, Albert wrote:

?

Hi Dave,

It seems that 672-0538-00 is a set containing not only the circuit board but also several other components:

In other words, the bare PCB is not for sale. A 670- is a bare board says Stan's book.

Albert

> There were apparently two different versions of the board
>
> 670-4177-xx and 672-0538-xx ( look at the 1st page on your parts list in
> the manual)
>
> It is not clear to me looking at my copies of manual which version the
> board overlays are for ...but this could explain the differences
>
> Dave

> > All my 7B80s have A1 board 670-4177-00. Actually, 670-417 is etched
> > and the last 7 is in ink. Probably because the same board cold be
> > prepared for use in a 7B80 (4177) or a 7B85 (4179 with a 9 in ink).
> > Albert

> > > Albert & John
> > >
> > > What is the part number of your respective boards
> > >
> > > Dave
> >
> >
>
> --
> Dave& Lynn Henderson
> Manuals@...
>
> PO Box 175
> Welch,MN 55089
>

-- 
Dave & Lynn Henderson
Manuals@...

PO Box 175
Welch,MN 55089

On Mon, Jul 16, 2012 at 5:55 AM, magnustoelle <magnustoelle@...> wrote:

Good Day,

a Tek 2101 pulse generator is on sale on ePay, see item # 150856739339.

And?

I have no affiliation with the seller.

Didn't think so, since it's being sold by Tektronix surplus!

?

Hi Dave,

It seems that 672-0538-00 is a set containing not only the circuit board but also several other components:

In other words, the bare PCB is not for sale. A 670- is a bare board says Stan's book.

Albert

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Albert

There were apparently two different versions of the board

670-4177-xx and 672-0538-xx ( look at the 1st page on your parts list in the manual)

It is not clear to me looking at my copies of manual which version the board overlays are for ...but this could explain the differences

Dave

On 7/16/2012 7:24 AM, Albert wrote:

?

Hi Dave,
All my 7B80s have A1 board 670-4177-00. Actually, 670-417 is etched and the last 7 is in ink. Probably because the same board cold be prepared for use in a 7B80 (4177) or a 7B85 (4179 with a 9 in ink).
Albert

--- In TekScopes@..., Artekmedia wrote:
>
> Albert & John
>
> What is the part number of your respective boards
>
> Dave

-- 
Dave & Lynn Henderson
Manuals@...

PO Box 175
Welch,MN 55089

Hi Dave,
All my 7B80s have A1 board 670-4177-00. Actually, 670-417 is etched and the last 7 is in ink. Probably because the same board cold be prepared for use in a 7B80 (4177) or a 7B85 (4179 with a 9 in ink).
Albert

Good Day,

a Tek 2101 pulse generator is on sale on ePay, see item # 150856739339.

I have no affiliation with the seller.

Cheers,

Magnus

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Albert & John

What is the part number of your respective boards

Dave

On 7/16/2012 5:53 AM, Albert wrote:

?

Hi John,

It's still confusing for me, is "the same results" what you found before? My board contains 3 ICs (Uxxx), not 2. I will send you pictures off-line.

Albert

-- 
Dave & Lynn Henderson
Manuals@...

PO Box 175
Welch,MN 55089

Hi John,

It's still confusing for me, is "the same results" what you found before? My board contains 3 ICs (Uxxx), not 2. I will send you pictures off-line.

Albert

Hi Fabio,

sorry to hear about that! Are you confident about this? No sign of life, if the trigger is set to AUTO & LINE, and inserted into a vertical compartment of your 7704A?

If you need any manuals, TekWiki is a great help on the 7B92A:


Cheers,

Magnus

On 07/15/2012 12:57 PM, keithostertag wrote:

Good News! We now have a working CRT and R7903!

The Short story: After replacing one resistor the screen came alive. After some adjustments there are two items remaining with this project that I need help with:

1. The readouts only gives one numeral. For instance, .5uS, 5uS, and 50uS all display as 5uS. Similarly, .5V, 5mV, and 50mV all say 5mV. Same for all settings, and regardless which plugins I use. The 10X multiplier makes no difference in the Readout display, though it does make it a little "wavy", like a slight vibration. Also, the Readouts are positioned a little low on the screen, so that the lower ones are half-obscured off the bottom of CRT frame.

2.) I'm going to need a source for some of the push-button switches on the front panel.

The longer story (for those interested):

I was following Albert's suggestion to check the continuity around P1675 when I found pin 3 to TP1883 measured around 5Meg ohms. When I went to touch one side of R1880 in order to lift it, it literally fell apart into two clean pieces. No burn or stress marks of any kind- and nothing else on that board was found bad.

After replacing R1880 the CRT came right up, and I went through both the PS cal as well as the z-axis cal. The are a few sections of the z-axis cal that I can't do (I guess) since I don't have a marker generator. (?)

I want to say that after all these weeks of working on this project I was immensely happy and relieved to see that first trace appear! My guess is that this R7903 had been sitting unused (due to its broken condition) for many years before it got to me. Many caps needed to be replaced on several boards, mostly the PS. Of course I would not have been able to do this without your help and instruction, and I am grateful for your patience and perseverance. Really a good example of group effort!

I know even _less_ about logic circuits than I do analog circuits, so fixing this Readout problem will be very interesting. I am reading the manual...

Your thoughts on how to approach the Readout problem?

Thanks,
Keith Ostertag

Keith,

Congrats on finally getting to the root of the problem. Now, if I could only have that "Ah Ha!" moment on this damn SC504 I've got. ;-)

Mark

Ouch! I managed to kill my only one timebase.
Probably inserting and extracting it with
the mainframe powered, now the 7B92A
doesnt trigger anymore, it triggered before :(

Fabio.

P.S. Yes I know, I shouldnt insert plugins
with the mainframe powered, also if the 7704A
manual tells that I can.

Fabio Eboli <fabioeb@...> ha scritto:

I'm still messing around with the 7704A.

Faulty parts:
Till now I found 3 shorted transistors in the
Z-axis board, for now I swapped them with normal
transistors, I will search better replacement
in future, the parts are Q4159 Q4183 Q4185.
I changed also Q4163 because it had a very low beta.
Also U2530 isnt working ok, it doesnt select B horizontal
timebase with the correct input combination.
In the diagram and measuring it, seem
that the output is high when pin 6 is at +1V,
and low when is slightly negative,am I correct?
The other faulty component is Q2577 with a beta of zero.
Q2577 and 2579 are selected parts, anyone knows what
are the selection criteria? Can I try to put in
normal npn transistors for now?

There is a little progress:
After replacing Q4159 Q4183 Q4185
I have the readout working on the screen,
also readout intensity regulation is ok.
The trace intensity regulation is still non
working. It remains very low, almost like
if the z-axis is blanking the screen.
Also I still dont have the sweep from the timebase.
When I use the TB in vertical bays it works, when I insert
into one of the 2 horizontal bays it doesnt generate the
sweep, but the horizontal position pot on the TB moves
the dot on the screen, so it's like the TB sweep is
disabled.

Fabio.

Fabio Eboli <fabioeb@...> ha scritto:

Oops, sorry I totally missed that.
I think I should read the manual before asking
such questions :)

Fabio.

Albert <aodiversen@...> ha scritto:

There is an extensive description of the U2530 Horizontal Binary
operation at page 2-15 manual.
Albert

anybody knows the function of the 155-0013-00 IC ?
---
Fabio.

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Albert Replied
-----------------------------
Hi John,
It seems that you mixed up two ICs. At my B058082 PCB, U722 is a round case CA3130, while U842 is a DIL labeled 0067-02 (741 in another unit). Both are correctly marked at the PCB and both are correctly shown in the PCB layout pictures and in the parts list.

Albert
----------------------

Hello Albert !
Thanks for replying .
Triple checked my downloaded manual and my 7B80 again and I get the same results.
The RCA IC (marked 0067-02 RCA 901) is marked U416 on the board and U416 on the schematic.and also on the board layout drawing , which are all correct., but my U416 is an 8 pin plastic mini dip, not a round cased one like your own, but that's not unusual.
The other IC is also an 8 pin mini dip marked on the schematic U722 with 3130 under it...this chip is coded 156-0067-02
The board layout drawing (1959 - 40) on my manual shows this chip to be U842, which is clearly different.
(Since there are only two IC;s on this board, apart from the 20 pin control chip, its hard to mix them up)
My manual only has one set of drawings and makes no reference to different S/N ranges
This manuals Change Reference at the rear 049/78 details adjustment text corrections only
My "Tektronix Part Numbers to Industry Standard" listing shows the 156 0067 -00 to be a 741 op amp and both are inter changeable on my board
My 7B80 S/N B058022 has the KE 4598-00 review board
Possibly this is an early board
My downloaded manual is referenced 070-1959-00 First Printing DEC 1975
My board has many unfilled inline pads around the time base switch and a large group of unused pads near the bottom right hand corner...looks like the same board was designed for a delaying time base model as well, probably the 7B85

Al this seems to show that , with the many revisions and changes in the manufacturing life of some of Teks boards that it 's understandable that Tek would make the occasional error in their drawings
Sometimes this results in two different versioned boards having radically different "U "chip designators from one another (Eg 7B90 (non A) which i've noticed on the on I am now working on)
Cheers, Albert and thanks for the trouble you've taken to check out your 7B80
I'me sure both our comments shall be useful one day to someone with a dud 7B80 out there
John

On 07/15/2012 06:12 PM, Rob wrote:

After whatever method people use to remove scratches. Are any applying a sealer of any kind and if yes what are you using?

Gel Gloss has some kind of silicone sealer as part of it.

ALLLLLLLLLLLLL ?RIGHTTTTTTTTTTTT ? ? ?YOU GOT IT!

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I am looking to buy a Tek IC part number 155-0018, zero logic chip. I can get one from Sphere, but the across-the-border shipping is silly high. Please contact me off-list if you have one for sale, Known good working used one OK.

This is used in 7000 series Readout circuit boards.

Keith Ostertag