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搁别苍é别, there is a lithium battery on the display & storage board which will probably need replacing; yes, the analyser will lose settings when the battery dies, however a nice feature of these analysers is that they can self calibrate and reset these values; there are some interactive settings, such as display positions that may need setting, but they are well documented in the manual. Let me know if you are having trouble finding a replacement battery, I had to buy several to satisfy the minimum order quantity from Conrad, so I have extras I'd be willing to sell.

That might be true, for something that is rarely used. If used at least
weekly, it will be fine. If it is a shelf queen, all bets are off.

On Thu, Nov 26, 2020 at 5:00 PM Glenn Little <glennmaillist@...>
wrote:

Baking the resistor will only fix it for the short term.
It will absorb moisture again as you have not fixed the problem, only
the symptom.
There is a crack or 0r other point of moisture incursion in the resistor
case.

The resistor needs to be replaced.

Glenn

On 11/26/2020 6:59 AM, Michael A. Terrell wrote:

Carbon Composition resistors absorb moisture. Bake them for a while

before

tossing them out. Also, high value resistors require voltage across them

to

work at their marked value This used to be plainly marked on reels of CC
resistors. I posted a scan once. I caught hell for 'making up that
bullshit'. They also don't realize the first resistor series was 50%
tolerance. yet they were working on pre-war radios. Once again I was told
that I was 'making up that shit'.

On Thu, Nov 26, 2020 at 12:18 AM Jeff Dutky <jeff.dutky@...>

wrote:

Tom,

Yes, I had anticipated that these NOS components might not have retained
their specified values. I've been going through my father's effects

while

working on his scopes and finding all sorts of now-50-year-old

components,

some of which were expensive when purchased new, and thinking that some
fair fraction of them are probably now terribly out of spec, if not
completely destroyed (there are a number of big metal can capacitors

that I

know were stored for at least 20 years in a hot attic, and I don't have
much hope that they are still in good condition). I purchased a dozen
resistors in the hope that I could find two that were within spec.

Back in college I worked in receiving QC for a NASA contractor that

built

flight-rated systems. We would first receive a lot of 10 or 20

components

of some description, which we would label and ship over to Goddard. They
would eventually ship us back 2 or 3 components with paint marks and
certification sheets, and we were required to use only those marked
components in the parts we built for them. The other components we had
shipped to them had been tested to destruction, and only the surviving

10%

had been returned to us as flight qualified components. Careful

selection

of parts is something I have thought about ever since.

But what you're saying is that while my intuition was correct, the

actual

math makes a fool of me. I should really just use the metal film

resistors

when they arrive because they are lower noise and the inductance is a
non-issue.

I can always gaze lovingly at the old Allen Bradleys. I'm quite sad that
nobody seems to make resistors that have those nice sharp edges anymore
(or, at least, I haven't found them for sale).

-- Jeff Dutky

--
-----------------------------------------------------------------------
Glenn Little ARRL Technical Specialist QCWA LM 28417
Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178
QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"

Hey Roger,

I tried cleaning the edge connector, but that didn't seem to help. So took
the head apart and gave the two pots as well as the board-to-board
connectors some D5 and I gave the pots each a wiggle. The "wobble" is now
gone and I have a rock-steady trace.
However, I clearly need to calibrate the head - not that it didn't already
need calibration. I guess I'll need to hunt for an extender (
) - people on
ePray sure are proud of their extenders...

In any case, thanks,
Siggi

On Mon, Nov 16, 2020 at 7:14 AM Roger Evans via groups.io <very_fuzzy_logic=
[email protected]> wrote:

Siggi,

There are two preset pots in the S6 head for gate balance (R30) and 'gain'
(R45), either could be noisy, but a more obvious suspect is the edge
connector from the S6 to the 7S12 since the DC / low frequency feedback
path has to travel through the edge connector.

Hi Jeff,
Shafts straightened with large pliers; they were only a little bent. Am considering grey PVC pipe as a knob replacement: the metal centres are still present so i just need to find a suitable diameter to fit over them.
For the 545B i have collected an assortment of eBay high voltage arc generators and LOPT's with which to experiment and replace the existing potted TX. The former have isolated secondaries, making them ideal. A theoretically possible option is some kind of large MW or LW coil that might fit over the ferrite core as a replacement secondary. I already tried driving the 6AU5 grid separately but this still takes more power than it should -and it is not difficult to have the 6AU5 anode glowing red. One could use an EL34 etc instead, assuming the unregulated 325V line has the spare capacity. Disaffected TEK EHT transformers need to operate at a lower frequency: from around 50 down to 45KHz or less. I wonder how they might manage with a 15KHz sawtooth via an EL34?
Regards

On Thu, Nov 26, 2020 at 10:46 PM, Raymond Domp Frank wrote:

At the time, the 466 was one of the fastest-storing GP portable analog storage
'scopes on the market, certainly in the 100 MHz BW range.

Sorry, incorrect. The HP 1744A was faster: 100 MHz BW, 1800 cm/us vs Tek 466 @ 1350 cm/us!
The HP was storage-only, with a very wide range of variable persistence; from almost zero to many seconds.

Raymond

On Thu, Nov 26, 2020 at 11:06 PM, Jeff Dutky wrote:

I was trying to keep the summary list short and sweet, so I omitted the A and
B versions (but included the M to illustrate the range of variation in the
models), as well as the lower bandwidth models.

Hi Jeff,
I guess you saw my comments on your summary; different summaries from different points of view, all very incomplete and personal to some degree...

Raymond

satbeginner wrote:

Add a 475A @ 250MHz to the list ;-)

I was trying to keep the summary list short and sweet, so I omitted the A and B versions (but included the M to illustrate the range of variation in the models), as well as the lower bandwidth models.

If you meant "add it to my wish list" then you're too late: I am currently restoring a 475A (as mentioned in a follow up)

-- Jeff Dutky

Baking the resistor will only fix it for the short term.
It will absorb moisture again as you have not fixed the problem, only the symptom.
There is a crack or 0r other point of moisture incursion in the resistor case.

The resistor needs to be replaced.

Glenn

--
-----------------------------------------------------------------------
Glenn Little ARRL Technical Specialist QCWA LM 28417
Amateur Callsign: WB4UIV wb4uiv@... AMSAT LM 2178
QTH: Goose Creek, SC USA (EM92xx) USSVI LM NRA LM SBE ARRL TAPR
"It is not the class of license that the Amateur holds but the class
of the Amateur that holds the license"

Congrats on getting your 2710 working!

In regard to manuals, there are several revisions of the 2710 manual, but try downloading one for the 2712, 2711, 2714, or 2715.

You will find that the analyzer models are very similar in the base design, with certain software or hardware differences depending on the intended market. The quality of the Tektronix manuals varies quite a bit; later ones usually have very good documentation and clarity for schematics and parts layouts, besides narratives explaining the circuit design, function, and operation.

Martin-
I just acquired a 2710...I know it has a battery....Does it store anything important that is lost if battery dies...like those NVRAM in some scope?
搁别苍é别

On Thu, Nov 26, 2020 at 10:49 PM, Dave Peterson wrote:

And know that there's an ocean out there waiting for me to wade into should I
care to.

Now I know what that landscape of about 50 'scopes, mainly Tek portables and 7000-series, around me really is.

Raymond

Ah, big heavy sigh. The human condition is just too limited: between turkey prep and having some lunch, the number of thoughts and threads gone through my head on this conversation is just too vast to begin to convey. I've apparently already hijacked this thread too far into the weeds as it is.
I'll just share: the taxonomy of Tektronix test equipment is so large that I just reflexively focus on what's in front of me. And know that there's an ocean out there waiting for me to wade into should I care to. I was startled to see the picture of the 475 - that it was like a 465 with a different digit in the logo. There's a whole other conversation I'd enjoy getting into regarding product development and history surrounding these scopes. I never knew the two were so closely related. So thanks to this thread there's a whole other bay into which I might sail this boat that I've just boarded. Sailing is an apt analogy. Patience Dave.
Happy Thanksgiving everyone. What a pleasant set of days it's been of late - joining in with you guys. Thank you everyone.Dave

Since you're giving a summary, I'd like to add some comments (my response embedded):

On Thu, Nov 26, 2020 at 09:52 PM, Jeff Dutky wrote:

Here is a quick summary of some of the models in the 400 series:

1. The older 45x family, consisting of the 453, 453A, 454 and 454A. Very solid and heavy construction.
2. The newer family, with very different construction, consisting of the 464, 465, 465B, 466, 468, 475 and 475A. These share the same frame (with size adaptions) and construction and almost the same main board.
3. The 455 and 465M are from the same generation, with very similar front layout. Their internal construction is different from the 464 - 475A group.
4. The 485, with its 350 MHz BW @ 50 Ohm / 250 MHz BW @ 1 MOhm, although from the same period as the series 2. has a very different internal and front panel layout. I consider it one of the best and most beautiful 'scopes from the period, although not the easiest to service. It is absolutely packed with dipped tantalum caps...

The 454 is a 150 MHz dual time base analog scope (fastest GP scope to NOT use
proprietary hybrid ICs)

AFAIK, the 454 was the first portable 'scope to employ Tek's revolutionary bridged t-coil circuit. It also used distributed vertical plates. Its slower brother was the 453 (50 MHz).

The 455 is a 50 MHz dual time base scope with a non-rectangular front profile
The 465 is a 100 MHz dual time base scope

The 465B is an upgraded 465, with fewer components, easier to assemble and adjust, and containing several Tek proprietary IC's.

The 465M is basically the same scope as the 465, but in the cabinet of a 455
(commercial version of the AN/USM 425)

The 455 is built like a 455, not just a 465 in a 455 *cabinet*, e.g. it has the plug-in vertical input and time base module construction of the 455.

The 466 is a 100 MHz dual time base scope with analog storage feature,
otherwise similar, if not identical to the 465.

At the time, the 466 was one of the fastest-storing GP portable analog storage 'scopes on the market, certainly in the 100 MHz BW range. It had a reduced scan mode, with a different CRT with smaller graticule divisions in the center of the screen and control electronics modified to achieve the faster storage.

The 464 is like the 466 but has much slower storage. It lacks the reduced scan mode.
The 466 is a 465 with analog storage, it's more than just similar: The storage board is mounted in front of a 465 main board.

The 468 is a 100 MHz analog scope with a 10 MHz digitizing feature, DMM, and
an ALT rather than MIX horizontal display mode

The 468 is built on the 465B base.

The 475 is a 200 MHz dual time base scope, basically a faster, but otherwise

functionally

identical version of the 465.

The 475A is a "tuned" version of the 475. It lacks the 2 mV/div max. vert. sensitivity of the 475.

The 485 is a 350 MHz dual time base scope with ALT horizontal display mode and
a different front panel arrangement.

The 485 has a completely different internal construction than the 465/475

There are some model numbers below the 454,

like the 453 (50 MHz) but they are all lower bandwidth and the 422 (15 MHz)

and I don't bother to think about them.

Raymond

On Thu, Nov 26, 2020 at 12:52:21PM -0800, Jeff Dutky wrote:

I should put the 468 on my wish list, and maybe the 454 as well, but that way lies madness.

-- Jeff Dutky

Well, if you want to enjoy the madness, I have a pair of 468s to get rid of. One was
working pretty much but is showing signs of bad filter caps and the other is a parts scope.

Shipping is the real killer, of course.

You may want to look for a 454A; it has a larger screen. I completely went through a 454
and use that one a lot. I have a 454A in the queue for one of these days; picked that one
up off of craigslist as nonworking for $35. If you look hard you can find those for $30-50.

Then of course you can move up to the 2400 series :-)

And the 7000 series

And you'll need a curve tracer by this point

And ...

Paul


--
Paul Amaranth, GCIH | Manchester MI, USA
Aurora Group of Michigan, LLC | Security, Systems & Software
paul@... | Unix/Linux - We don't do windows

The copy of the manual I have is not helpful in regards to cabling, there are no illustrations showing where the various connectors are located. By careful checking of the layout for every board, I was eventually able to determine what goes where and all appeared OK. I did adjust the routing, particularly around the CFC board as a lot of cables cross over each other and I found at least 1 cable was fully snapped into place; that was obviously the problem as it's all working now and appears to be accurate based upon my signal source; I have a higher frequency generator which I'll also try as the one I'm currently using maxs out at 30MHz.
Now I can use it to repair my HP spectrum analyser!

Add a 475A @ 250MHz to the list :-)

Dave wrote:

Is the 465B and the 475A the same too? Is the difference bandwidth? Doesn't seem that it'd
be release date as the 465B seems more advanced than the 465. I seem to recall we preferred
the "B" and thought it was the newer more advanced model.

Yes, the A and B models were later revisions of the un-suffixed models, and were usually better in some ways.

The 475A, for example, has a bandwidth of 250 MHz, but I have been told that it has "worse pulse response" as a result of the higher bandwidth. It also lacks a 2 mV range on the vertical channels, which is certainly a regression.

I'm currently restoring a 475A that I bought as a parts scope for my father's 475. It was quite evidently sick, and since the essence of my hobby is to diagnose and fix sick devices, I decided to try putting it back in working order rather than part it out. I fixed the bad +110V rail almost by accident, and am now working on the beam intensity amplifier (which had several diodes and transistors completely blown). Sadly, it looks like that might be all that is electronically wrong with the 475, and my fun will be over in a couple of week when the replacement transistors arrive.

I'm also fixing up my father's 2213, which has something marginal in the channel 1 vertical system, I have some residual marginality with his 475 involving cross talk in the vertical system and some stiff/scratchy pots, and I have a 2215A that I fixed the horizontal position adjustment on, but requires some adjustment to the 2 mV range on channel 1. So there's other fun to be had, but nothing quite as exciting as the repair required by the 475A.

Learning engineering minutia AND history and product lines.

Engineering is just the minutia of history with extra math.

-- Jeff Dutky

Jeff-..according to some most of here are already mad....and it only gets worse. Do not ask me why or how I personally know......
搁别苍é别

Dave,

There are a wide range of scopes in the 400 series. The 465 and 475 share a common design and have many parts in common. The main difference between them is about 100 MHz in bandwidth :-P

Here is the TekWIki page on the 400-series scopes

Here is a quick summary of some of the models in the 400 series:

The 454 is a 150 MHz dual time base analog scope (fastest GP scope to NOT use proprietary hybrid ICs)
The 455 is a 50 MHz dual time base scope with a non-rectangular front profile
The 465 is a 100 MHz dual time base scope
The 465M is basically the same scope as the 465, but in the cabinet of a 455 (commercial version of the AN/USM 425)
The 466 is a 100 MHz dual time base scope with analog storage feature, otherwise similar, if not identical to the 465
The 468 is a 100 MHz analog scope with a 10 MHz digitizing feature, DMM, and an ALT rather than MIX horizontal display mode
The 475 is a 200 MHz dual time base scope, basically a faster, but otherwise identical version of the 465
The 485 is a 350 MHz dual time base scope with ALT horizontal display mode and a different front panel arrangement

There are some model numbers below the 454 but they are all lower bandwidth and I don't bother to think about them.

I should put the 468 on my wish list, and maybe the 454 as well, but that way lies madness.

-- Jeff Dutky

Real stunners!!!