Date   

Re: Hello everyone @ tekscopes

mwcpc7@...
 

In a message dated 11/1/00 5:52:38 PM Eastern Standard Time, sjhel@...
writes:


I checked out the SND tube sales site the other day & discovered that
Tektronix used to make a valve curve tracer (the 570). I do quite a
lot of work on old valve equipment, (usually fixing guitar amps for
friends) & it would be great to test the valves I have to see how
well they match. Many amps that come in have an assortment of valves
where one has been replaced when it has finally expired instead of a
new matched set being fitted.

The 570 is a very rare item even here in the US. A friend of mine had one and
sold it to a collector for a quite high price. You can see that very unit on
the cover of Alan Douglas's "Tube Testers and Classic Electronic Test Gear".
According to the book, only about 1000 were made over a period of ten years,
starting in 1956.

Mike Csontos


Re: Parts needed

Arnoud van der Wel <A.P.vanderWel@...>
 

Hi Michael,

I have the pot here for you.

Can you give me a postal address?

Regards,

Arnoud.

-----Original Message-----
From: Michael [mailto:mdd@...]
Sent: Sunday, October 22, 2000 11:18 AM
To: TekScopes@...
Subject: Re: [TekScopes] Re: Parts needed



Hiya. :)

Sometime on Tue, 17 Oct 2000, you wrote:

-Do you know the Tek part number?
-I know a guy who just bought an assortment of Tek pots.
Yep. Part number is: 311-1404-00

Hope you can help...

Thanks and regards,
:)
Michael

--

Michael VK2XMD 0404-478-205 http://members.dingoblue.net.au/~mdd/
I used to have a handle on life, but it broke ...


-------------------------- eGroups Sponsor
-------------------------~-~>
eGroups eLerts
It's Easy. It's Fun. Best of All, it's Free!
http://click.egroups.com/1/9698/12/_/_/_/972206558/
--------------------------------------------------------------
-------_->

To unsubscribe from this group, send an email to:
TekScopes-unsubscribe@...



Re: 1S1 repair news :-)

jlamesch@...
 

--- In TekScopes@..., Michael Dunn <mdunn@c...> wrote:
As for the six missing GaAs diodes in the sampling bridge and
elsewhere, I got some SMT Schottky diodes as hopeful subs. The
unit
is now working somewhat - there are some triggering and offset
problems. But, with the right settings and input, I can get a
valid
trace!!! Whether these probs are a result of the Schottkys, I
don't
yet know. All I can say is, it's VERY cool to scroll over a 200MHz
waveform at 35ps/div! (yes, 35ps. 0.035ns!) Though a bit
useless,
as the risetime of the thing is *only* about 300ps...
Hi,
replacing the GaAs diodes with Schottkys sounds extremly
interesting. Could you write which type of Schottky diodes you
used? I think a lot of (potential) sampling plugin repairers
would appreciate this information, at least I would.

Thanks a lot,
Laurent Lamesch


Re: Hello everyone @ tekscopes

Stan or Patricia Griffiths <w7ni@...>
 

Hello Stuart,

Welcome to this group of Tek scope fans!

The type 570 Tube Curver Tracer is probably the most desired of early Tek
scopes. This also makes is rare and expensive. Tek only made about a
thousand of them and most of the remaining ones are in the hands of "glass
audio" enthusiests who value them very highly. Pristine ones are worth
about $3000 USD in the Far East, as I understand it. You would be very
lucky to find one at any price . . . I have one in my collection, but I was
lucky to find it in an estate sale in a barn about 30 miles from my home
near the orignal Tek plant. Mine is a proto-type and was built before
regular production on them started. I got it for $40 USD, as I recall it.

You might find the web page dedicated to early Tek scopes at
<http://www.reprise.com> to be of interest to you. There is a list of
people who can supply manuals or copies of manuals there for Tek
instruments. I sell some manuals myself on eBay so you might want to check
that out too.

I have a rather huge collection of old Tek stuff (665 instruments) and I
might be able to help you solve some of your 545B/CA problems if you
describe them to me. You will need manuals for each of those instruments
and it would help if you had them first so we can have a common ground for
discussing the circuitry.

Stan
w7ni@...

Stuart Hellier wrote:

I have been looking for other fans of vintage tektronix stuff for
ages! I have an old 545b unit with ca dual trace plug in module, but
I have a few problems with it & have not been able to find a service
manual.

I am a sound engineer from the U.K & no one seems to know much about
old tek gear (including tektronix U.K)! So if any of you guys could
lead me to any technical data or service manuals, it would be most
helpful.

I checked out the SND tube sales site the other day & discovered that
Tektronix used to make a valve curve tracer (the 570). I do quite a
lot of work on old valve equipment, (usually fixing guitar amps for
friends) & it would be great to test the valves I have to see how
well they match. Many amps that come in have an assortment of valves
where one has been replaced when it has finally expired instead of a
new matched set being fitted.

Thanks to stefan for the T & M museum, theres some useful &
interesting stuff in there, & I enjoyed looking through the exhibits.

Bye for now, I shall log on again soon!


To unsubscribe from this group, send an email to:
TekScopes-unsubscribe@...


Re: Parts needed

Michael <mdd@...>
 

Hi Arnoud, :)

Sometime on Thu, 02 Nov 2000, you wrote:

-Hi Michael,
-I have the pot here for you.
-Can you give me a postal address?
Sure can. :)

Michael Dunn
PO Box 103
Woodford NSW 2778
Australia

How would you like me to pay you for it...?

Thanks and regards,
:)
Michael

--

Michael VK2XMD 0404-478-205 http://members.dingoblue.net.au/~mdd/
I used to have a handle on life, but it broke ...


mdd@dingoblue.net.au

Arnoud van der Wel <A.P.vanderWel@...>
 

Hi Michael,

Sorry: the request for you address should have gone to you directly, not to
the list.

I don't need payment; happy to be able to help you out.

Regards,

Arnoud.

-----Original Message-----
From: Michael [mailto:mdd@...]
Sent: Friday, November 03, 2000 5:58 AM
To: TekScopes@...
Subject: RE: [TekScopes] Re: Parts needed



Hi Arnoud, :)

Sometime on Thu, 02 Nov 2000, you wrote:

-Hi Michael,
-I have the pot here for you.
-Can you give me a postal address?
Sure can. :)

Michael Dunn
PO Box 103
Woodford NSW 2778
Australia

How would you like me to pay you for it...?

Thanks and regards,
:)
Michael

--

Michael VK2XMD 0404-478-205 http://members.dingoblue.net.au/~mdd/
I used to have a handle on life, but it broke ...


-------------------------- eGroups Sponsor
-------------------------~-~>
eGroups eLerts
It's Easy. It's Fun. Best of All, it's Free!
http://click.egroups.com/1/9698/12/_/_/_/973227761/
--------------------------------------------------------------
-------_->

To unsubscribe from this group, send an email to:
TekScopes-unsubscribe@...



Re: Hello everyone @ tekscopes

sjhel@...
 

Hi stan, thanks for the website info. Stefan has kindly offered to photocopy
his 545b manual so that's one hurdle crossed.
The problems i'm having with my 545b are:

The trace stops and becomes a stationary dot once the scope has been on for
around 10-15 minutes.

Channel A of the CA plug in does not match the voltage settings of CH B even
when adjusting the gain pot.

Horizontal display selections other than B and B intensified by A only
display a dull "cloudy" hue, occasionally showing a trace as you turn the
time / cm control.

I have a tube tester & tested all tubes for quality and leakage & they all
checked out okay so I guess these problems are to do with other parts of the
circuitry.

Bye for now

Stuart


Re: 1S1 repair news :-)

Michael Dunn <mdunn@...>
 

At 5:13 PM +0000 2000/11/02, jlamesch@... wrote:
Hi,
replacing the GaAs diodes with Schottkys sounds extremly
interesting. Could you write which type of Schottky diodes you
used? I think a lot of (potential) sampling plugin repairers
would appreciate this information, at least I would.

Thanks a lot,
Laurent Lamesch
Giving you part numbers would not be too useful, since the 1S1 still has the offset problems I mentioned. I got a couple of different types through Digikey. If you want to experiment, I expect it's best to look for low-capacitance parts, say, 1-2pF. I'll get back to the 1S1 when I have time. It *is* a weird circuit, and difficult to troubleshoot, even with the manual!

BTW, the Sept 18th Electronic Design has a design idea circuit that's very similar to the Tek design, but modernized and simplified. Quite a coincidence!

-----------------------------------------------------------------
Michael Dunn | Surround Sound Decoder & Stereo Enhancement
Cantares | Self-Amplified Speakers, Test Equipment
74 George St. | Ambisonic Surround Sound CDs and Recording
Waterloo, Ont. | (519) 744-9395 (fax: 744-7129)
N2J 1K7 | mdunn@...
Canada | http://www.cantares.on.ca/
-----------------------------------------------------------------


Re: Hello everyone @ tekscopes

Stan or Patricia Griffiths <w7ni@...>
 

sjhel@... wrote:

Hi stan, thanks for the website info. Stefan has kindly offered to photocopy
his 545b manual so that's one hurdle crossed.
The problems i'm having with my 545b are:

The trace stops and becomes a stationary dot once the scope has been on for
around 10-15 minutes.
Most scope problems, it seems, are in the power supplies. I would check the
power supplies to make sure they are still regulating when the problem shows up.
It would be helpful to know if both A and B sweeps stop at the same time or if it
is just one of them.

Channel A of the CA plug in does not match the voltage settings of CH B even
when adjusting the gain pot.
On this problem, I would like to know if it appears that the gain is too low or
too high and which channel seems to have the problem? Is the same problem
evident in all setting of the volts/div switch or is it just one position?

Horizontal display selections other than B and B intensified by A only
display a dull "cloudy" hue, occasionally showing a trace as you turn the
time / cm control.
Since the trace seems to be there only occasionally, it sounds related to the
first problem you mentioned.

The dull "cloudy" hue may be due to faceplate clouding on the CRT. Take a close
look at the pads cushioning the CRT inside of the shield at the faceplate. Are
these BLACK foam rubber or are they sort of orange-brown in color? If it is a
strip of black foam-like material, this is bad news and needs to be replaced with
different cushion material. There was a chemical reaction between the material
that bonds the plastic implosion shield to the front of the CRT and the black
cushion material that results in the bonding material in front of the CRT turning
cloudy. There is a cure for this and I can share more information with you about
it if the cushion materials are black or you thing the CRT faceplate bonding
material has become cloudy.

I have a tube tester & tested all tubes for quality and leakage & they all
checked out okay so I guess these problems are to do with other parts of the
circuitry.

Bye for now

Stuart
OK Stuart, we are started now and the 545B is certainly worth the trouble to
fix.

Stan
w7ni@...


FS/For Trash? Type 502 Dual Beam Oscilloscope

Jeramy Ashlock <ashlock@...>
 

Hello, I just rescued an old 502 Dual Beam Oscilloscope that
was about to be thrown out, tubes and all. It is in
slightly beat up shape. I am wondering if it would have any
value to anyone here, or should I just trash it?

What do you think I could I get for this thing on ebay?


Re: FS/For Trash? Type 502 Dual Beam Oscilloscope

Michael Dunn <mdunn@...>
 

At 2:30 PM -0700 2000/11/03, Jeramy Ashlock wrote:
Hello, I just rescued an old 502 Dual Beam Oscilloscope that
was about to be thrown out, tubes and all. It is in
slightly beat up shape. I am wondering if it would have any
value to anyone here, or should I just trash it?

What do you think I could I get for this thing on ebay?
Not sure what you could get on eBay, but don't trash it! I'll pay you a reasonable amount for stripped parts if you don't want to keep it together. Shipping intact might be prohibitive. Does it have PCB vertical amps, or little sub-chassis with ceramic strips?

-----------------------------------------------------------------
Michael Dunn | Surround Sound Decoder & Stereo Enhancement
Cantares | Self-Amplified Speakers, Test Equipment
74 George St. | Ambisonic Surround Sound CDs and Recording
Waterloo, Ont. | (519) 744-9395 (fax: 744-7129)
N2J 1K7 | mdunn@...
Canada | http://www.cantares.on.ca/
-----------------------------------------------------------------


Re: FS/For Trash? Type 502 Dual Beam Oscilloscope

Stan or Patricia Griffiths <w7ni@...>
 

Hi Jeramy,

An old Tek scope like a 502 always has SOME value but whether it is worth
the cost the box and ship it is a good question. It is always a good idea
to offer these things to the list but it would be helpful to know WHERE it
is located to know if one could pick it up without boxing and shipping. As
to what it might be worth on eBay . . . good question. I have sold tons of
stuff on eBay and I have really been surprised at what some of it went for.
I have also put some stuff up for auction that never got a single bid . . .
sometimes I have relisted a "no bid" item and gotten good bids on the second
try. It is hard to guess what will happen on eBay. Here is my guess at
what it is worth: If it looks dead with no trace when you plug it in and
turn it on: $10.00. If it has a trace and appears to work: $25.00. A
little more if it has a manual and/or probes or a scope cart. I already
have two of them plus two 502A models but I would still find a place for it
here to save it from the landfill if it was close to here and I could get it
just for picking it up.

Stan
w7ni@...

Jeramy Ashlock wrote:

Hello, I just rescued an old 502 Dual Beam Oscilloscope that
was about to be thrown out, tubes and all. It is in
slightly beat up shape. I am wondering if it would have any
value to anyone here, or should I just trash it?

What do you think I could I get for this thing on ebay?


To unsubscribe from this group, send an email to:
TekScopes-unsubscribe@...


Re: FS/For Trash? Type 502 Dual Beam Oscilloscope

mwcpc7@...
 

In a message dated 11/03/2000 9:56:55 PM Eastern Standard Time,
w7ni@... writes:

It is hard to guess what will happen on eBay. Here is my guess at
what it is worth: If it looks dead with no trace when you plug it in and
turn it on: $10.00. If it has a trace and appears to work: $25.00. A
little more if it has a manual and/or probes or a scope cart. I already
have two of them plus two 502A models but I would still find a place for it
here to save it from the landfill if it was close to here and I could get
it
just for picking it up.

Stan
w7ni@...
My experience is about the same. I have 5 or 6 502s and would really like to
have one operating on each bench that I use for audio work, but they really
need thorough servicing and recapping. I burned out two transformers before
I learned not to turn them on. I have paid $0.00 to $25.00 for them.


I would pick up any similar vintage Tek equipment that are available for the
hauling within 50 miles of Rochester, NY or $5 to $15 for one that sits in
front of me at a Hamfest. At that rate I get about all I can handle.

Mike Csontos


Tek 7B87 Question

Don Crano <donc@...>
 

I know the 7B87 plug in is designed to support the features of the 7854
frame, but can it be used in a 7904 frame, or is it strictly for the 7854
frame?

Thanks,
Don


Re: Tek 7B87 Question

mhaubmann@...
 

Dear Don!

The 7B87 is a timebase that features a pretrigger aquire clock to
enable a pretrigger otion in the digital storage mode of the 7854.

It works in all other 7k scopes i own.

The main disadvantage of this timebase is that it does not have the
delta delay or normal delay for a delayed timebase. Also the
independent/runs after delay/triggerable after delay button is not
available because it will control the pretrigger operation.

When You use it as delayed timebase (eg with a 7B15 or 7B85) it will
work fine. (similar to a 7B80)

Michael B. Haubmann
mhaubmann@...


--- In TekScopes@..., "Don Crano" <donc@s...> wrote:
I know the 7B87 plug in is designed to support the features of the
7854
frame, but can it be used in a 7904 frame, or is it strictly for
the 7854
frame?

Thanks,
Don


Re: Tek 7B87 Question

Stan or Patricia Griffiths <w7ni@...>
 

HI Don,

The 7B87 can be used in any 7000 series main frame, including the 7904.

Stan
w7ni@...

Don Crano wrote:

I know the 7B87 plug in is designed to support the features of the 7854
frame, but can it be used in a 7904 frame, or is it strictly for the 7854
frame?

Thanks,
Don

To unsubscribe from this group, send an email to:
TekScopes-unsubscribe@...


looking for part

Hong F Du <feng@...>
 

Hi All,
Where can I get parts for Textronix 7104 scope? I need the vertical
channel switch IC. The component number is U668. Thank you in advanced.


Feng


What to do with a pile of 7A16P's?

 

We have a pile of 7A16P's, the programmable version of the 7A16, used
in waveform digitizers like the 7912D and 7612AD. Unfortunately, we
have no digitizers, so these are worthless to us, and do NOT work in
regular frames. Rats.

Other than landfill, any suggestions? Note that we have lots of
other mor useful Tek items, parts and CRTs on our website here:
http://www.sphere.bc.ca/test/index.html

Also have about 150 pounds of partial and failed 5K/7K plug ins we
are scrapping. Free to anybody that wants to pay the freight. We
are also looking for CRT's, nixie tubes and HP repair parts.

all the best,
walter

@walter2


Re: What to do with a pile of 7A16P's? CADC?

Michael Dunn <mdunn@...>
 

At 4:24 PM +0000 2000/11/09, walter shawlee wrote:
We have a pile of 7A16P's, the programmable version of the 7A16, used
Other than landfill, any suggestions?
Strip off any easily strippable parts, hardware, knobs, etc, and sell grab bags of Tek parts.


Also have about 150 pounds of partial and failed 5K/7K plug ins we
are scrapping. Free to anybody that wants to pay the freight. We
are also looking for CRT's, nixie tubes and HP repair parts.
Tempting :-) Could you post a rough list of 7000 modules...? Any particularly "interesting" ones? (7C,D,L,M,Snn)

BTW, is the 5000 series a successor to the 7000, or concurrent? What's the difference? I'm quite amazed at the tube/SS overlap - the 7000 series started to happen in the late 60s, yet tube units were produced till perhaps 1973(?).

Semi-related question for Canadians out there: Anyone know if CADC (Crown Assets Disposal Corp) or a successor is still in operation? I used to get all sorts of interesting junk through them.

-----------------------------------------------------------------
Michael Dunn | Surround Sound Decoder & Stereo Enhancement
Cantares | Self-Amplified Speakers, Test Equipment
74 George St. | Ambisonic Surround Sound CDs and Recording
Waterloo, Ont. | (519) 744-9395 (fax: 744-7129)
N2J 1K7 | mdunn@...
Canada | http://www.cantares.on.ca/
-----------------------------------------------------------------


1A5, 1A7

Michael Dunn <mdunn@...>
 

Does anyone know the difference between the 1A5 and 1A7 differential plug ins?

thx

-----------------------------------------------------------------
Michael Dunn | Surround Sound Decoder & Stereo Enhancement
Cantares | Self-Amplified Speakers, Test Equipment
74 George St. | Ambisonic Surround Sound CDs and Recording
Waterloo, Ont. | (519) 744-9395 (fax: 744-7129)
N2J 1K7 | mdunn@...
Canada | http://www.cantares.on.ca/
-----------------------------------------------------------------