Topics

I wonder if there is much interest in vacuum tube oscilloscopes such as the 500 series

John Williams
 

Hi folks. I have been observing the topics of interest here for a few weeks, and I am not seeing much on older scopes ie before the 7000 series. I am just wondering if this is a temporary trend or is it too late. Has all interest in the restoration and repair of these old “boat anchors” gone somewhere else, or has it died altogether? I am still working on several projects bringing new life to the ‘50s and ‘60s units. I hope I am not the last of a dying breed. Regards, John

Phillip Potter
 

Hi John,

I suspect that it's just a matter of what's going at the moment. I have seen a number of older scopes being worked on and written about here, over time.

I have a 575 that I intend to use, but it's not on my near horizon... LOL!

Phil

On 3/27/2019 6:07 PM, John Williams wrote:
Has all interest in the restoration and repair of these old “boat anchors” gone somewhere else, or has it died altogether?

Dave Seiter
 

It's probably just temporary; at least I hope it is.  I've limited myself to the 7K series and earlier, omitting the portables.  Have to draw the line somewhere!
-Dave

On Wednesday, March 27, 2019, 6:08:22 PM PDT, John Williams <books4you@...> wrote:

Hi folks. I have been observing the topics of interest here for a few weeks, and I am not seeing much on older scopes ie before the 7000 series. I am just wondering if this is a temporary trend or is it too late. Has all interest in the restoration and repair of these old “boat anchors” gone somewhere else, or has it died altogether? I am still working on several projects bringing new life to the ‘50s and ‘60s units. I hope I am not the last of a dying breed. Regards, John

toby@...
 

On 2019-03-27 9:07 PM, John Williams wrote:
Hi folks. I have been observing the topics of interest here for a few weeks, and I am not seeing much on older scopes ie before the 7000 series. I am just wondering if this is a temporary trend or is it too late. Has all interest in the restoration and repair of these old “boat anchors” gone somewhere else, or has it died altogether? I am still working on several projects bringing new life to the ‘50s and ‘60s units. I hope I am not the last of a dying breed. Regards, John
Hi,

As a relatively recent member, I'm unlikely to ever own or have space
for a tube Tek, but I'm thrilled to know that people are keeping them
alive. As many as possible, I hope.

Please keep discussing them on the list!

--Toby





Brad Thompson
 

Phillip Potter wrote on 3/27/2019 9:46 PM:

Hi John,

I suspect that it's just a matter of what's going at the moment. I have seen a number of older scopes being worked on and written about here, over time.

I have a 575 that I intend to use, but it's not on my near horizon... LOL!
Hello--

Next question: is anyone out there building an oscilloscope from scratch? (*)

If so, I have one only used/RFE cast-aluminumfront-panel  bezel for a 5-inch CRT.
Manufactured by JAN Hardware of Brooklyn, NY (AKA Cylex), the casting
is their part number C-JAN-1358; the finish is a tasteful matte black and
has some scuffs.

I'm offering it free for postage plus another buck for a cuppa coffee.

Questions welcomed, PayPal honored
Thanks, and 73--

Brad  AA1IP

(*) I did this, sort of, as a teenager in the late 1950s when I was given a used
and nonworking Heathkit oscilloscope model O-something in lieu of a week's
wages at a TV-repair shop.

The scope's performance was dismal in all respects, so I undertook improvements.
What an education-- I learned about power supplies, triggered-sweep circuits, and
amplifier bandwidth compensation-- all tubed, BTW. The Radio Amateur's handbook and  a
copy of USAF Manual 52-8 (RADAR Circuit Analysis) were my texts.

I lacked tools for cutting holes in the scope's steel chassis. One of the first items to go
was the original cabinet, which was in the way of various aluminum subchassis
hung on the sides. At one point, I acquired a flat-face CRT which replaced the
original 5BP1 and greatly improved trace resolution.

All told, I learned a lot from that project!

Harvey White
 

On Wed, 27 Mar 2019 18:07:51 -0700, you wrote:

Hi folks. I have been observing the topics of interest here for a few weeks, and I am not seeing much on older scopes ie before the 7000 series.
Well, there's the 400 series, of which I had some, and still have
468s. I have a Telequipment D75 which was well loved at one time (and
put aside for other, more sophisticated equipment).

I am just wondering if this is a temporary trend or is it too late. Has all interest in the restoration and repair of these old “boat anchors” gone somewhere else, or has it died altogether? I am still working on several projects bringing new life to the ‘50s and ‘60s units. I hope I am not the last of a dying breed. Regards, John
I'm not equipped any more to do tube scope restoration. I have no
more tube equipment other than an old Drake R4-B receiver.

For lab scopes, I'm likely to stay at the 7000 series for now. Other
than a 7854 (which I don't need..........) there's nothing much in the
7000 series that I could make use of.... maybe a 7912A or the like...
but I don't need any of them.

For portable, I can go to 150 Mhz, digital or analog, up to 4 channels
depending....

For really portable, I'd kinda like a 225 or so, but not only are they
hard to come by, but also expensive. A 222 would be neat, but again,
while less expensive, not something I *have* to have.

Newer than that I have a TDS-540A and a TDS-640A. The only thing I'd
like in that kind of thing would be a color display....

So seriously enough, the older scopes (535, 545, 585) aren't
attractive, I've used them in the past. The even older ones (512,
513D), I've had and just don't need any more (and those were passed on
to someone else many years ago).

For what I do, and what I need, the 7000 series is pretty good.

Harvey




John Williams
 

It seems like most people here would actually use a scope. The other side would be those of us that don’t have scopes to use, but to restore and preserve. I only use a scope to fix a different scope, or some associated equipment. And for that I use the 475 or 2213. So I won’t try to guess which is the dark side. But there is a distinct difference. And never acquire anything you can’t fix. Probably that is.

Leanna L Erickson
 

I have a bunch of 500 series working scopes.

Real room heaters.

Keith

Wayzata, mn.

On Mar 27, 2019, at 9:52 PM, John Williams <books4you@...> wrote:

It seems like most people here would actually use a scope. The other side would be those of us that don’t have scopes to use, but to restore and preserve. I only use a scope to fix a different scope, or some associated equipment. And for that I use the 475 or 2213. So I won’t try to guess which is the dark side. But there is a distinct difference. And never acquire anything you can’t fix. Probably that is.


Morris Odell
 

I still use a 547 as my main bench scope and a 575 to test semiconductors.
Fortunately I have the skills to maintain them. I have several 7000 series
and a DSO but don't need their facilities very often. Later model Tek curve
tracers are very rare and expensive down here in Australia.



The 547 is a wonderful scope, and works perfectly even though it's over 45
years old.



Morris

Brian
 

Hi everyone , I also have 500 series scopes , 547 , 2 x 549 and a 564 . I even have a 661 that still works . I like all these scopes and will hang on to them as long as I have the space as they are all reminders of my early working life as they (547,549 and 564) were all new and state of the art when I started work
Despite my liking of these I also have a number of 7000 series scopes and even a couple of TDS scopes , one of which I am attempting to repair as for me buying broken ones and fixing them is the only way I can afford any of them having retired now .

Brian

Daniel Koller
 

There's still an interest!    I have a 575 (used irregularly) and a 545 (used OFTEN).   but it just works every time I turn it on.   I haven't needed to fix it in a few years.    I completely disagree that the 500 series are useless "boat anchors" or "room heaters" .   Yes, they are bigger than a modern scope, but if you have the bench space, they are every bit as useful.   Mine are on carts.  More so, for general experimenting, there are a lot input and out put connections on the 545 made by banana jacks (on my older version).   that makes it very easy to set up an experimental setup, rather than to just monitor a signal.   It's a great scope to *use*!
  Dan

On Thursday, March 28, 2019, 7:07:02 AM EDT, Brian via Groups.Io <brianas1948=yahoo.co.uk@groups.io> wrote:

Hi everyone , I also have 500 series scopes , 547 , 2 x 549 and a 564 . I even have a 661 that still works . I like all these scopes and will hang on to them as long as I have the space as they are all reminders of my early working life as they (547,549 and 564) were all new and state of the art when I started work
Despite my liking of these I also have a number of 7000 series scopes and even a couple of TDS scopes , one of which I am attempting to repair as for me buying broken ones and fixing them is the only way I can afford any of them having retired now .

Brian

Dave Voorhis
 

On 28 Mar 2019, at 01:07, John Williams <books4you@...> wrote:

Hi folks. I have been observing the topics of interest here for a few weeks, and I am not seeing much on older scopes ie before the 7000 series.
I have a 549 with Type Z, 1A2 and 1A4 plugins. I love it and it just works, though I need to do some mechanical restoration work on one of the 1A4 channels.

I also have a 564 which produces a trace and the storage works, but I need to fix the plugins.

I haven’t posted about them much because so far I haven’t encountered anything on them I felt the need to ask questions about.

I’d like to get my hands on a 575, but here in the UK they’re relatively rare.

bill koski
 

I still have a 556 which I built my own cart for. I have it next to my test bench and use it often. I bought it with the manual for $25 at a HAM fest about 15 years ago. Other than needing a vertical driver tube (which cost me 30 bucks at the time) it has worked great. I have a bunch of plugins for it including a 1L5 Spectrum analyzer (a subject for another day that I'll have to pick the brains of the people here!) and a 1A4 4 channel plug in. Friends are impressed when I use a 2 channel in the other bay and can put 6 different traces up on the screen! Though it's only rated 50MHz I've displayed a stable 100MHz on it.
Amazing scope for its time and still quite a performer today. Plus it keeps me warm in my office on cold winter nights!!!
I also have a single bay scope that I acquired with some other equipment. I believe it's a 545B? I've not even attempted to plug it in yet. It's sitting in the wings waiting for some much needed TLC.
While we're on the subject does anyone have an extension cable for the plugins that they would like to sell so I can work on a couple sick ones?

Nenad Filipovic
 

My 536 serves as a lab power supply for occasional tube experiments.
Otherwise is in excellent condition, complete and functional, and will keep
it as such. On winter evenings I sometimes fire it up with covers off, when
some of my vintage-fan friends drop by for a visit. 536 is an X-Y
instrument, so with 2 CA plugins we once played stuff like
https://www.youtube.com/user/jerobeamfenderson1

A year ago I rescued a 555 about to be ripped apart by audiophools.
Restored it to a quite decent condition, but alas I do not have its power
supply, only the mainframe. Still looking for one.

Dave Wise
 

I have a small fleet of 500-series, all daily runners. Each needed sorting when I got it but since then has gone for years without missing a beat.
535
535A
545
547
B,C,CA,D,G,H,K,L,O,TU-7,Z,1A1,1A2,1A4,1A5,1A7,1S1
132

All restored by me except the O and 132 which are in the queue.

Dave Wise
________________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of Leanna L Erickson <lle@...>
Sent: Wednesday, March 27, 2019 8:40 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] I wonder if there is much interest in vacuum tube oscilloscopes such as the 500 series

I have a bunch of 500 series working scopes.

Real room heaters.

Keith

Wayzata, mn.
On Mar 27, 2019, at 9:52 PM, John Williams <books4you@...> wrote:

It seems like most people here would actually use a scope. The other side would be those of us that don’t have scopes to use, but to restore and preserve. I only use a scope to fix a different scope, or some associated equipment. And for that I use the 475 or 2213. So I won’t try to guess which is the dark side. But there is a distinct difference. And never acquire anything you can’t fix. Probably that is.


Brenda
 

Hello John!

I have noticed the same trend myself. But I have am very interested in these 500 series scopes, for me, they are a real pleasure to use and at the time, reminds me of how much thought and work was put into these scopes. I have picked up a Tektronix 535A with the Type 202-2 cart. The 535A came with a CA plug-in and a Type L plug-in. Spent 2 weeks cleaning all the cigarette smoke out of the scope and the CA plug-in. Unfortunately, I was not able to save all the lettering on some of the tubes due to the amount of smoke. It was so bad that the tubes would actually stick to your hands! But after cleaning the scope, powered it up, and I couldn't believe my eyes, the darn thing works perfectly, or I think so as I need to get a manual. I know that I could download a manual but I am old school and prefer the actual manual. At the same time, I also picked up a 533A with another CA plug-in, and I am sure that I will be asking questions about that soon enough along with the 535A and the 545A.


Brenda

Kevin Wood G7BCS
 

I wonder if the lack of 500 series chat is down to them "just working" and
not needing much tweaking?

I have a 546 + 1A2 that came home from school in a wheelbarrow in my early
teenage years. It was donated to the school by a local firm (Marconi, if
memory serves) but was too complex for their purposes. A bit of
negotiation and it was mine! 30+ years later I've still got it and the
only thing I've had to do is swap in one of Chuck's rewound HV
transformers, although the trigger on one of the timebases has started to
play up, so I might be on the look out for a tunnel diode soon.

Kevin
G7BCS

Dave Wise
 

Oh, I forgot, I also have a 1L5. I haven't used it aside from restoring it; I prefer my HP 141T/8556A.

Most recent repair: 1S1 unstable Memory Balance. Cause: Zener in the heater current regulator intermittently going open-circuit. There was also a manufacturing defect (?) that had a pass transistor pin touching the heat sink.

Most recent use: 535+B, viewing transistor breakdown. I was trying to distinguish between avalanche mode and punch-through. I got self-contradictory results. The 2N1304 required shunt capacitance to break down, which suggests it was avalanche, but reverse bias on the base didn't affect it much, which suggests punch-through. BC337 is the reverse, not needing a cap but being sensitive to bias.
I initially used the 1S1, to confirm that the rise time was less than 1ns, but it's no good for viewing the overall waveform because unless you include a lot of attenuation ahead of the bridge, there's risk of blowing it due to capacitive coupling of the fast edge. I guess I need one of those 500-ohm or 5000-ohm resistor probes.

Dave Wise
________________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of Nenad Filipovic <ilmuerte@...>
Sent: Thursday, March 28, 2019 7:57 AM
To: TekScopes@groups.io
Subject: Re: [TekScopes] I wonder if there is much interest in vacuum tube oscilloscopes such as the 500 series

My 536 serves as a lab power supply for occasional tube experiments.
Otherwise is in excellent condition, complete and functional, and will keep
it as such. On winter evenings I sometimes fire it up with covers off, when
some of my vintage-fan friends drop by for a visit. 536 is an X-Y
instrument, so with 2 CA plugins we once played stuff like
https://www.youtube.com/user/jerobeamfenderson1

A year ago I rescued a 555 about to be ripped apart by audiophools.
Restored it to a quite decent condition, but alas I do not have its power
supply, only the mainframe. Still looking for one.

Keith Knox
 

--------------------------------------------

Hi All,

I have a 25ft. X 13 ft. room full of Tektronix Series 500 scopes. 75 plus scopes.
Some of these scopes are fully refurbished and working well. Others need work or full refurbishing. These are listed below. My goal is to get them all refurbished.

1 @ Type 570 Curve Tracer --- Fully Refurbished
2 @ Type 575 Curve Tracer --- Both Working -- 1 @ Fully Refurbished
1 @ Type 175 High Current Adaptor --- Not tested yet -- Need Cable
3 @ Type 585A ------------- All Need Work -- None working yet
2 @ Type 585 --------------- All Need Work -- None working yet
2 @ Type 556 ---- Both Fully Refurbished and working well. -- Both on Carts
5 @ Type 555 - 3 Refurbished - 2 Need work - 4 extra Power Supplies - on carts
4 @ Type 551 - 1 Refurbished - 3 Need Work - 1 on cart
8 @ Type 549 -- 2 Working -- 6 Need Work -- 2 on cart
6 @ Type 547 -- 2 Working -- 4 Need Work -- 2 on cart
3 @ Type 546 -- 3 Need Work
5 @ Type 545B -- 5 Need Work -- 2 on cart
3 @ Type 545A -- 3 Need Work
2 @ Type 545 ---- 2 Need Work
1 @ Type 543 -- 1 Needs Work
2 @ Type 541 --- 2 Need Work
4 @ Type 536 -- 1 Working -- 3 Need Work -- 1 on cart
4 @ Type 535A -- 2 Working -- 2 Need Work -- 2 on cart
2 @ Type 535 --- 2 Need Work
3 @ Type 524AD -- 3 Need Work
1 @ Type 519 -- 1 Needs Work
1 @ Type 503 ---- 1 Working
1 @ Type 502A --- 1 Needs Work
3 @ Type 502 --- 3 Need Work
2 @ Type 561B - 2 Need Work
1 @ Type 564 -- ! working

I am retired now so I hope to spend my time getting as many of these scopes Refurbished as I can. Also have a smaller collection of 7000 Series scopes and 2400 series scopes.

Keith Knox

On Wed, 3/27/19, John Williams <books4you@...> wrote:

Subject: [TekScopes] I wonder if there is much interest in vacuum tube oscilloscopes such as the 500 series
To: TekScopes@groups.io
Date: Wednesday, March 27, 2019, 6:07 PM

Hi folks. I have been observing the topics of
interest here for a few weeks, and I am not seeing much on
older scopes ie before the 7000 series. I am just wondering
if this is a temporary trend or is it too late. Has all
interest in the restoration and repair of these old “boat
anchors” gone somewhere else, or has it died altogether? I
am still working on several projects bringing new life to
the ‘50s and ‘60s units. I hope I am not the last of a
dying breed. Regards, John

Thomas Dodge
 

Hi, I am actually working on a Tektronix 535 scope and it is in fairly good condition, but I need some advice with the high voltage. When I turn it on, and after it warms up, the CRT will light up, but I can't get a trace. What is a good way to discharge the high voltage before you do anything else? Thanks.