Date   

Re: Adjusting CAL01 – 2467B s teps 17 thru 34

Chuck Harris
 

Yes, for 17, pick the pulse that gives you the
easiest overlap.

I haven't noticed that the last 4 steps (31 through 34)
are all that critical. They were added only for the
newest scopes... I expect that the older scopes sometimes
needed a part change during their initial calibration
which became unnecessary in the later scopes thanks to
these added steps.

-Chuck Harris

dosmith54@... [TekScopes] wrote:

Thank you Chuck,

Step 17 only has two pulse, I'll use the second one. Yes I just finished
calibrating all my generators, their spot on. As for steps 33 and 34, not seeing
much difference from one sweep end to the other, is this normal?

Dallas


Re: Adjusting CAL01 – 2467B s teps 17 thru 34

Dallas Smith
 

Thank you Chuck,

Step 17 only has two pulse, I'll use the second one. Yes I just finished calibrating all my generators, their spot on. As for steps 33 and 34, not seeing much difference from one sweep end to the other, is this normal?

Dallas


Re: Adjusting CAL01 – 2467B steps 17 thru 34

Chuck Harris
 

I always go for the middle possibility. The pulse on either extreme
will cause the superimposition to separate.

Most positions have 3 possible pulses that could be right, but some
have 5... in all cases, pick the middle.

-Chuck Harris

OBTW, before you calibrate your 2465 family scope for the first time,
you should always verify/calibrate your calibration tools. The scopes
are much more long term stable than are the TG501/PG506/SG503/4
calibration tools.

dosmith54@... [TekScopes] wrote:

To any resident expert,

I’m in the process of re-calibrating my 2467B a second time since the manual that
was purchased from Qservice didn’t have the procedures’ for steps 32 thru 34, the
Arktekmeadia manual did. Anyway which pulse do I use on the bench scope pulse 1 or
2? If I superimpose the pulse at pulse one and scroll over to pulse two it’s not
superimposed but close. I think pulse two should be used because the sweep may not
be linear for pulse one? I’m at step number 17, will wait for answer.

Dallas







------------------------------------ Posted by: dosmith54@...
------------------------------------


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

Yahoo Groups Links


Adjusting CAL01 – 2467B steps 17 thru 34

Dallas Smith
 

To any resident expert,

I’m in the process of re-calibrating my 2467B a second time since the manual that was purchased from Qservice didn’t have the procedures’ for steps 32 thru 34, the Arktekmeadia manual did. Anyway which pulse do I use on the bench scope pulse 1 or 2? If I superimpose the pulse at pulse one and scroll over to pulse two it’s not superimposed but close. I think pulse two should be used because the sweep may not be linear for pulse one? I’m at step number 17, will wait for answer.

Dallas


Re: Welcome

Ed Breya
 

I agree - a 5000 series scope would be better for primarily audio work. I think there's a 5A22 equivalent to 7A22 high gain differential amp. This would be good for much lower-level audio signals into the uV range.

The down side is that there's no on-screen readout or plug-in counter available.

The 7000 series would be a step up in features, but not necessarily in display quality, except for particular models. The 7603 still has the bigger, slower, MSE-less CRT that looks nice like the 5000 series, and readout. The 7A22 and a counter plug-in along with an appropriate sweep plug would be a pretty decent setup for audio work.

The 2465B is a nice all-around scope with modern convenience features, plenty of bandwidth, and is newer than the others (but not without its own problems) - if I had to have only one scope, that would be it.

It's hard to beat a stand-alone counter - even a simple one - for just general purpose frequency readout. The scope plug-in or built-in types can be more complicated, and have limited display readout, but probably are adequate for normal use. If the anticipated frequencies to be counted are only in the audio range, then most counters won't provide many digits of display anyway - typically 1 Hz resolution with a 1 second gate, so 2 to 5 digits.

You'd need a reciprocal type counter to get very high resolution at low frequencies with reasonable gate times, but I doubt if this sort of thing is needed in audio work. I don't recall what counting methods are available in the various scopes, but it would be evident from the specifications.

Ed


Re: PG-506 General info

Mitchell Kobierowski
 

Jack,
Since I started this thread, I guess I should try and answer your questions.


I have a 2445B and two 2465's that I will need to eventually calibrate. Since I have the two different models, I am having to use two different manuals for the repair and adjustments of the scopes. In reading through the two manuals, they are pretty much identical with the exception the 2465 has a couple of more steps for the higher bandwidth. In reading through the manuals, the only time the SG-504 is used is in section 4 (same sections in both manuals) to verify certain portions of the scopes operation. It is not used in section 5 which is the adjustment (calibration) section of the manual. So, from what I have read, the SG-504 is not necessary to calibrate the scope. Others can correct me if I am wrong on this point. I have not yet performed the calibration, I have just read through the manuals in preparation to perform the calibration and to determine what equipment would be necessary to perform the calibration.


The surplus seller is called BMI Surplus out of Massachusetts. I do not know if they have any of the plug-ins left.


There is a very extensive thread (Tektronix 2465B teardown) over on the EEVBLOG group that explains most anything you would ever want to know about the Dallas NVRAM modules used in these series of scopes. Well worth the read. I'm sure you can find the same information in this group, just a bit more searching.


The 2465 does not have a battery backed up NVRAM. No issue with data loss from battery failure


The 2465A does have a battery backed NVRAM (same as 2465B), but that model has a separate battery that can be carefully replaced without loosing the calibration constants. If the backup battery dies, you loose the calibration. I don't currently have a service manual for the 2465A, but I think it uses the same Dallas DS1225Y chip the 2465B uses.


The 2465B (and 2445B) uses the Dallas DS1225Y battery backed NVRAM. The problem with this NVRAM is that the battery is actually inside the DS1225Y module, and there is no way to replace the battery without replacing the Dallas module. Now if you have not yet lost your calibration constants (back up battery died) you can go into diagnostics, run EXER 02 and copy down the calibration information that is displayed on the screen. If you loose your data while replacing the Dallas chip, you can download one of the BIN file for your scope from the net, replace the sections in the bin file with the data you copied down from EXER 02, and restore your current calibration. A bit of work, but it saves having to recalibrate the scope. I replaced the Dallas chip in my 2445B with the RAMTRON chip on a daughter board. The different chip works with no problems, and no battery back up worries on that scope.


Mitch


Re: Welcome

Gary Robert Bosworth
 

I was wondering the same thing.

Gary
On May 19, 2015 7:09 AM, "HankC @HankC [TekScopes]" <
TekScopes@...> wrote:



Just curious why a high freq scope & an "accurate" counter is needed for
audio work.I would thing a 5K series scope would be perfect for audio . . .
large screen, sensitive plug-ins, much lower noise, etc.
HankC, Boston
WA1HOS





Re: Welcome

 

Just curious why a high freq scope & an "accurate" counter is needed for audio work.I would thing a 5K series scope would be perfect for audio . . . large screen, sensitive plug-ins, much lower noise, etc.
 HankC, Boston
WA1HOS


Re: SMT chip replacement

Craig
 

On the topic of SMT replacement the subject of moisture may deserve mention.

All plastic parts absorb moisture over time and some parts are very sensitive to delamination (the plastic package expands and breaks the wire bonds between the silicon die and package leads).

Delamination is also called pop-corning because sometimes you can actually hear the IC "pop" from the expanding moisture inside when it is heated.

All plastic ICs are rated with a MSL (moisture sensitivity level) by the manufacturer and can be found on the data sheet. This is the maximum time the part can be exposed to room atmosphere before assembly onto the circuit board.

IC customers don't like to buy ICs rated above 3 because they cause logistical problems on the assembly floor. But there are a lot of MSL3 parts out there, especially larger ICs.
MSL 6 – Mandatory Bake before use MSL 5A – 24 hours MSL 5 – 48 hours MSL 4 – 72 hours MSL 3 – 168 hours MSL 2A – 4 weeks MSL 2 – 1 year MSL 1 – Unlimited MSL is important if you are removing an IC that you need to reuse or keep alive.



If you need to remove an IC from a board for reuse, it is good practice to bake the board over night at 75C to 100C to remove the moisture, unless you know for sure that the IC is rated MSL 1.


Best to everyone,

Phil


Re: Welcome

Siggi
 

On Tue, 19 May 2015 at 05:55 karl.simpson@... [TekScopes] <
TekScopes@...> wrote:

I think I will pursue my aim in getting a model with the CTT option as
the triggering options may be of benefit. I have used later Tek scopes at
work with enhanced triggering so have some familiarity with what is
available. I did find the spec for the Option 06 and the counter tolerance
is well within my requirements (whilst in calibration!).

I should mention that the CTT option is not entirely without cost; because
the triggers are routed through the option board, you get higher jitter and
delay.

As mentioned the later model will be less likely to need the capacitors
replacing but a 2465B would be around 20 years old now so some
refurbishment would be of benefit sometime soon (agreed?)
Many of the 2465Bs have SMT on the A5 control/readout board. There are SMT
capacitors on that board that are extremely prone to leakage, and probably
ought to be changed ASAP.
The other maintenance is the NVRAM. It's a Dallas chip with a built-in
battery, and when the battery goes, so do your calibration constants.
My 2467 has a date code of 85 on the keeper, and it's still going strong,
though as I'm equipped to calibrate the scope I'm not too worried.


One final question, I have seen a scope with 18757 hrs run and 1566 power
cycles (it is a 2465B, Serial No. B014618). Is this typical and could it
have be reset?
The counter is not a reliable indicator of the lifetime usage. The
calibration procedure has a step "CAL 05", where one step is "d. Press and
release the lower TRIGGER SOURCE and then press and release the lower
TRIGGER MODE to reset HRS ON and PWR ON/OFF to zero." - e.g. the intent
seems to be to count hours from last calibration.
If there's a calibration sticker on it, you can perhaps extrapolate to the
lifetime usage...


Re: Tek 2440

mosaicmerc
 

Sounds like drying out caps.

Change the batch , anything over 0.2ESR at >470uF size is weak.


Re: Welcome

karl.simpson@...
 

Thank you for your replies, they are appreciated.

I think I will pursue my aim in getting a model with the CTT option as the triggering options may be of benefit. I have used later Tek scopes at work with enhanced triggering so have some familiarity with what is available. I did find the spec for the Option 06 and the counter tolerance is well within my requirements (whilst in calibration!).

As mentioned the later model will be less likely to need the capacitors replacing but a 2465B would be around 20 years old now so some refurbishment would be of benefit sometime soon (agreed?) The parametric measurements this later model provides would be useful so I seem to have narrowed down the scope I’m looking for.

One final question, I have seen a scope with 18757 hrs run and 1566 power cycles (it is a 2465B, Serial No. B014618). Is this typical and could it have be reset? The hours run per power cycle seems quite high (12hrs).

Regards,

Karl


Re: Tek 2440

Jeff Woolsey
 

On 5/18/15 7:23 PM, Jeff Woolsey jlw@... [TekScopes] wrote:


On 5/17/15 2:19 PM, atb6npt@... [TekScopes] wrote:


Out of circuit, the ESR meter says 1098 uF, ESR 8.7 ohms for C262.
1172uF by DMM. Should be 840.
1699uF, 3.3ohms ESR for C455. 1800uF by DMM. Should be 1200.
The ESR charts I've seen indicate those caps should be 0.2 to 0.1 or
less. Yours seem really high- probably should be replaced before more
troubleshooting. They ARE your +5VD rectifier caps!
I'll try to scare some up.

I did scare some up. Well, close-ish. Marked 1000uF 25V, the ESR says
about 980uF, 4ohms each. Installed them anyway, no improvement over
when the original caps were there. 5VD still reads around 4.2V, but I
also measured it at the "fuse", and got around 4.7V. It may easily have
been that last time--I just didn't think to measure it. I suppose I
should ascertain whether that's the ammeter drop. It is. Shorting the
ammeter gives me 4.9V there, and 5VD comes up to 4.3V. Still, schematic
says it should be 5.12V.

Interesting. in the +5V PREREGULATOR FEEDBACK, U189-5 is 5.103V, pin 6
is 4.319V. pin 7 is 1.216V. While I'm here, pin 1 is -0.005V, pin 2 is
20.43V, pin 3 is 9.998V.

Perhaps C184 is shot? What do I know? More poking later.

--
Jeff Woolsey {woolsey,jlw}@jlw.com,first.last@{gmail,hp,jlw}.com
Nature abhors straight antennas, clean lenses, and empty storage.
"Delete! Delete! OK!" -Dr. Bronner on disk space management
Card-sorting, Joel. -Crow on solitaire


Re: OT: WTB or hhave printer cables donated!

Richard R. Pope
 

Druid,
We would appreciate it. Yes, we do check out these different
places. The problem is is that since most people have finished their
upgrades the supply of 25 wire printer cables has crashed. A few years
ago you could find them for about one dollar each. Now you almost never
see any. Our St. Vincents and the one Baraboo quit accepting computer
equipment about two years ago.
Thanks,
rich!

On 5/18/2015 2:26 PM, Druid Noibn druid_noibn@... [TekScopes] wrote:

Hi.,
I'll look at my collection - don't know yet if there will be anything
of vlue.

HOWEVER - look for a local recycle business (metal) - they usually get
lots of cables and, if you talk nice, they will charge you little more
than what was paid per pound. Next - check your town recycle or
collection station - talk even nicer..... NOTE that town usually
contract with a company and sell such material, so they might not be
inclined to talk to you. I would also suggest "Curb-Mart" shopping,
however, it is illegal in many communities (some sell the metals) and
I don't wish to suggest anyone breaking the law.
Be well,DBN


On Monday, May 18, 2015 10:31 AM, "mechanic_2@... [TekScopes]"
<TekScopes@...> wrote:


Hello all,
We are making good progress on our railroad. We are using printer
cables for the logic wiring. Could someone who has a bunch of printer
cables please donate them or sell them for little or nothing to us?
Six footers are usable and nine footers are great.
Thanks,
Richard R. Pope
President
Reedsburg Area Model Railroad Club, RAMRC
1230 19th Street #5
Reedsburg, WI 53959
608-768-7448
mechanic_2@...


Re: Printer cables?

Richard R. Pope
 

Brad,
Yes, Yes, and Yes.
Thanks,
rich!

On 5/18/2015 3:21 PM, Brad Thompson brad.thompson@... [TekScopes]
wrote:

Hello, Richard--

What type of printer cables do you need (e.g., those with a 25-pin male
D connector
on one end and a Centronics connector on the other)?

Also, I can offer you a box of 50 female 25-pin D connectors designed
for right-angle
PC-board mounting.

Finally, would you be willing to pay for a medium-size flat-rate USPS
Priority-mail shipment to cover the cost of shipping the cables? If so,
I'll dig through my collection and see what's available.

Thanks, and 73--

Brad AA1IP


Re: PG-506 General info

Jack Reynolds
 

Hello Everyone,
I am a relatively new member, although I have been following your topics for a couple of months.  I have done so in the hopes that I could become familiar enough with the scopes I would like to work on and gain enough of the incredible collective wisdom of this group so as to not appear foolish on my first post.  I do not believe I have yet accomplished either, but I am overwhelmed by curiosity with regards to this post which I have quoted partially below.  I will apologize in advance if I am breaching any protocol here.  I also have a couple of 2400 series scopes (a 2465 and a 2465A) which I would like to eventually be able to calibrate.   Based on the information in the 2465 Service Manual, Tek specifies an SG 504 Leveled Sine Wave Generator for use with these scopes.  I am curious as to the mention of an SG 503 here.  I gather that the 503 is cheaper and does not require the additional expense of the leveling head which the 504 does.  However, if I understand correctly the 503 is frequency limited to 250 mhz.  As the 2465 is a 300 mhz, scope and the 2465A is a 350 mhz. scope, the Tek specification of the 1ghz. 504 seems to make sense.  Can the 503 actually be used for this purpose?  Does the surplus company on the east coast have a name or would I have to be killed if told?  As I have already surrendered my anonymity and opened myself to scorn,  I will hazard an additional question with regard to the parameter storage in the 2465 and 2465A.  As everything I have read about the data loss/battery failure disasters refer to 2465B scopes.  Am I correct in assuming that the 2465 and 2465A do not share this problem?  Thank you all for your patience.  Please be gentle in your replies!!
Jack Reynolds
"As many if you are aware, I have three 2400 series scopes that will be needing calibration touchups. After weighing the options available to me, I decided to locate a PG-506 Calibration Generator, a SG-503 Leveled Sine Wave Generator, and appropriate TM-503 series main frame to put them in. I located the PG-506 and SG-503 from a surplus company on the east coast for a reasonable price (way less than -bay prices), and the TM-503 from -bay. I have been traveling the past 10 days, arriving home late last night. The PG-506, SG-503 and TM-503 mainframe arrived while I was away. I had a chance to check them over today. Physically they appear to be in good shape. After a through visual inspection of the internal circuit boards looking for obvious damage, I installed the plug-ins in the mainframe and applied power. No smoke, and everything seemed to be working. There is a question with the PG-506 and the reason for this post."

On Monday, May 18, 2015 3:19 PM, "Jack Reynolds jackandladyreynolds@... [TekScopes]" <TekScopes@...> wrote:


On 5/16/2015 9:10 PM, mskobier@... [TekScopes] wrote:
Hello Everyone,
I am a relatively new member, although I have been following your topics
for a couple of months.  I have done so in the hopes that I could become
familiar enough with the scopes I would like to work on and gain enough
of the incredible collective wisdom of this group so as to not appear
foolish on my first post.  I do not believe I have yet accomplished
either, but I am overwhelmed by curiosity with regards to this post
which I have quoted partially below.  I will apologize in advance if I
am breaching any protocol here.  I also have a couple of 2400 series
scopes (a 2465 and a 2465A) which I would like to eventually be able to
calibrate.  Based on the information in the 2465 Service Manual, Tek
specifies an SG 504 Leveled Sine Wave Generator for use with these
scopes.  I am curious as to the mention of an SG 503 here.  I gather
that the 503 is cheaper and does not require the additional expense of
the leveling head which the 504 does.  However, if I understand
correctly the 503 is frequency limited to 250 mhz.  As the 2465 is a 300
mhz, scope and the 2465A is a 350 mhz. scope, the Tek specification of
the 1ghz. 504 seems to make sense.  Can the 503 actually be used for
this purpose?  Does the surplus company on the east coast have a name or
would I have to be killed if told?  As I have already surrendered my
anonymity and opened myself to scorn,  I will hazard an additional
question with regard to the parameter storage in the 2465 and 2465A.  As
everything I have read about the data loss/battery failure disasters
refer to 2465B scopes.  Am I correct in assuming that the 2465 and 2465A
do not share this problem? Thank you all for your patience.  Please be
gentle in your replies!!
Jack Reynolds

All,
As many if you are aware, I have three 2400 series scopes that will be
needing calibration touchups. After weighing the options available to
me, I decided to locate a PG-506 Calibration Generator, a SG-503
Leveled Sine Wave Generator, and appropriate TM-503 series main frame
to put them in. I located the PG-506 and SG-503 from a surplus company
on the east coast for a reasonable price (way less than -bay prices),
and the TM-503 from -bay. I have been traveling the past 10 days,
arriving home late last night. The PG-506, SG-503 and TM-503 mainframe
arrived while I was away. I had a chance to check them over today.
Physically they appear to be in good shape. After a through visual
inspection of the internal circuit boards looking for obvious damage,
I installed the plug-ins in the mainframe and applied power. No smoke,
and everything seemed to be working. There is a question with the
PG-506 and the reason for this post.



Thanks
Mitch

[Non-text portions of this message have been removed]



[Non-text portions of this message have been removed]



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

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Yahoo Groups Links


Re: Tek 2440

Jeff Woolsey
 

On 5/17/15 2:19 PM, atb6npt@... [TekScopes] wrote:


Out of circuit, the ESR meter says 1098 uF, ESR 8.7 ohms for C262.
1172uF by DMM. Should be 840.
1699uF, 3.3ohms ESR for C455. 1800uF by DMM. Should be 1200.
The ESR charts I've seen indicate those caps should be 0.2 to 0.1 or
less. Yours seem really high- probably should be replaced before more
troubleshooting. They ARE your +5VD rectifier caps!
I'll try to scare some up. Meanwhile it occurred to me that I could use
my shiny new variable DC power supply to feed the 5VD, after isolating
it from the LVPS (removed fuse). Scope behavior improved (but is still
insane) in that the front panel seems to be alive to the extent that the
trigger lights all change and the relays click sometimes. Of course,
it's hard to coordinate powering both on at the right time, so this
behavior, while repeatable, wasn't predictable.

See http://www.youtube.com/watch?v=eXMAR1TF_Lc for a video of it doing
these things. Ignore the dryer noise. The voltage reported on the DC
supply measures lower than displayed by a couple hundred mV.
__
--
Jeff Woolsey {woolsey,jlw}@jlw.com,first.last@{gmail,hp,jlw}.com
Nature abhors straight antennas, clean lenses, and empty storage.
"Delete! Delete! OK!" -Dr. Bronner on disk space management
Card-sorting, Joel. -Crow on solitaire


New Tek rear feet - Have a look! 384-0339-00 Lives again!

 

Ok, I've done the testing, taken the pics, now you can see everything here on the new Tek rear cord-wrapping feet for the 465/475 series at Sphere:

http://www.sphere.bc.ca/test/tekfeet.html http://www.sphere.bc.ca/test/tekfeet.html
I will order 50 feet tuesday for our stock, if anybody wants these new feet, let me know (off list!), I will add them to the order. The page shows how they are made, how they look and work, and what was improved. I have added a FEET /384 link from the Tek parts area in the main gateway, and they are also on the new arrivals page.

I also dug through all our spares, and put all the other Tek feet we have on the same page (more than I thought) so it's easy to see them all at once. If I come up with more, I will add them. Often that one elusive foot is all you need to make your instrument stop wobbling around...

All comments and thoughts welcome. This was months of work to get organized, and a lot of favors to make it actually happen, but at least now we have workable fix for this really annoying problem. If anybody wants more insight into the new design and how it was done, let me know. I'm sure most of you will figure it out just by looking at the pics. The new foot is ABS, the screw is an aerospace hardened steel screw, and the anti-skid insert is rubber.

all the best,
walter (walter2 -at- sphere.bc.ca)
sphere research corp.
http://www.sphere.bc.ca


Re: Tek 2467 front cover needed

Joe
 

I have a latching cover Tektronix PN 200-2742-00, that I believe fits a number of 24XX scopes. Where are you located? $40 + shipping. Let me know if you are interested, need pictures or dimensions. Thanks,

Joe


Printer cables?

Brad Thompson <brad.thompson@...>
 

Hello, Richard--

What type of printer cables do you need (e.g., those with a 25-pin male D connector
on one end and a Centronics connector on the other)?

Also, I can offer you a box of 50 female 25-pin D connectors designed for right-angle
PC-board mounting.

Finally, would you be willing to pay for a medium-size flat-rate USPS
Priority-mail shipment to cover the cost of shipping the cables? If so,
I'll dig through my collection and see what's available.

Thanks, and 73--

Brad AA1IP