Date   
Re: Tek 555 part needed.

zerousair
 

Just to close this out: The HV supply I received from a person here from one of his 555's has fixed the lower beam problem. Stabilized correctly at -1350 volts. I haven't disassembled the old supply and checked all the caps yet or ohmed the burnt transformer.

Re: TDS 380 calibration and vertical scale problem

David Wilson
 

It looks like I am in a real bind desoldering ch2 hybrid from the mainboard. The joints are through hole and some of the joints I was able to get the solder off at the top but at the bottom there is suborn solder that just refuses the come out. I tried desoldering several times but not having much luck. Since I don't want to break anything I thought about putting it back back the way it is and just use as is. A partially working scope is better than a broken one.

I could use a soldering iron to flow solder back in the through hole and try to desolder once again. The board is about 4 mm thick approximately and so are the through hole joints.

Re: 468 sweep offset issue

Brian Bloom
 

I didn't get to do much today, but I checked the waveforms at the disconnect amplifiers for A and B.

The waveforms sync up, but the A disconnect amplifier (at emitter) is .5V high ( -2V instead of -2.5V) and the B disconnect amp ( at emitter) is .3V high ( at -2.6V instead of -3V).

I'll do more tomorrow - hopefullly I will have the time to check the entire sweep logic section and find the out of tolerance resistor(s). It appears that is what I should be looking for... (am I correct?)

Re: 468 sweep offset issue

Brian Bloom
 

Hi,
>since you are saying one is ok and this one is out a little…..check all all the settings of every knob on the >timebase side and compare knob to knob…...….both a and b and start/end and hold off to make sure you are >seeing what you think….

>jim

There is only one apparent difference between the scopes other than the A/B sweep start misalignment.

On the "good" 468, B sweep ends 1 minor division before A sweep.
On the "bad" 468, A and B sweep end at exactly the same point.

Other than that, there are no other differences that stand out.


I am going to upload some more pictures that I took just to confirm that what I am seeing is normal. It is the same on both scopes: ( I put info for each photo in the comments)

All about classic Tektronix CRT o'scopes https://groups.yahoo.com/neo/groups/TekScopes/photos/albums/1461836945

https://groups.yahoo.com/neo/groups/TekScopes/photos/albums/1461836945

All about classic Tektronix CRT o'scopes https://groups.yahoo.com/neo/groups/TekScopes/photos/albums/1461836945 All about classic Tektronix CRT oscilloscopes, their use, repair, and collecting. (If you want to join, please make sure you write something relevan...



View on groups.yahoo.com https://groups.yahoo.com/neo/groups/TekScopes/photos/albums/1461836945
Preview by Yahoo






Also, I had myself a little bit confused. The bowing problem is with the 468 that I am not currently working on.

Re: 468 sweep offset issue

Jim Popwell <jpopwell@...>
 

Hi,

since you are saying one is ok and this one is out a little…..check all all the settings of every knob on the timebase side and compare knob to knob…...….both a and b and start/end and hold off to make sure you are seeing what you think….

jim

On Feb 24, 2016, at 3:53 PM, analogaddict013@... [TekScopes] <TekScopes@...> wrote:

I am not sure what you mean by voltage offset. With no sweep, there
is always a voltage offset because the blanked beam is located at the
left side of the CRT.
Is the bow on the right 1/4 of the CRT visible in your photos?
It is only slightly visible in the close up photo. It is most noticeable when I have the scope set up per the calibration procedure for Y axis and Geometry adjustment. I will upload a photo of the display symptoms shortly.

According to the schematic for the horizontal amp, when the scope is set up in XY mode (as per the voltage measurement conditions) both plates should measure close to 52V. My 110V rail is 2V high, so it should measure 54V, but either way they should both be the same with the dot centered. Left plate measures 56.7V and Right plate measures 54.3V.
The horizontal position control is off-center to the right side of the display by approx 2 divisions.
Also, when I center the trace in a normal timebase setting and then switch it into XY, the dot is positioned that same 2 division to right offset.

Are you referring to the start point of the A and B sweeps not being
exactly aligned?
The alignment depends on circuit tolerances and there may be no
adjustment for it. At high sweep speeds, it is normal for the start
of the sweep to creep to the right somewhat.
I can probably suggest where it can be trimmed out if we determine
that there is no actual fault.
Yes, I am referring to the A and B sweeps not being aligned. My other 468 doesn't have this problem at any timebase settings. (That one needs more work than the one being discussed.)

What really bothers me about it, and also has me slightly confused, is how to properly adjust the sweep start and sweep cal settings when taking this problem into account.

As per the horizontal cal procedure (it's the first step in this section):
-Set timebase A to 1ms and B to 5us
-Set delay time to 1.00
-Input 1ms time markers
-Adjust so the pulse displayed on B sweep starts at the beginning of the sweep & start of 2nd time marker from A sweep display**

The pulse on B sweep is not displayed if I set it to where I believe it should be - which is coinciding with the start of A sweep (which is the first time marker)
If I don't have it set exactly there, won't B sweep end up being out of tolerance?

I suppose I'll have to go through the waveforms again now that I have a digital scope and see if everything syncs up with the sync pulse, A and/or B sweep start, and blanking/unblanking. When I had checked them with my 465, everything appeared to be correct. Some waveforms just had minor differences in their voltage levels when compared against the manual spec, but seemed OK when compared against the other 468.

I definitely want to fix this and get them aligned. I guess I'm a bit OCD...

I just have a couple things to do and then I can get another picture or two uploaded, then do some waveform checking.





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Re: Tek 7854 Info, Repair, Restore

Brian Bloom
 

You would not need the 7S11 at all but using the 7S12 as a sampling
>sweep requires the S-53 Trigger Recognizer head which is shown in the
>photo. This configuration gives roughly the capability of a 7T11
>without the random sampling capability so a delay line would be needed
>to see the triggering edge.

>I think the delay line is more rare and expensive than a 7S14 which is
>why I recommended the later. The 7T11 and 7T11A do away with needing
>the delay line as well because of their random sampling capability but
>are more difficult to use than a 7S14.

I just haven't been able to find any 7T11, 7T11A, or 7S14 plugins thus far. There are a few 7S12, S53, sampling plugins, and 7M11 plugins available right now, though.

Re: 468 sweep offset issue

Brian Bloom
 

I am not sure what you mean by voltage offset. With no sweep, there
>is always a voltage offset because the blanked beam is located at the
>left side of the CRT.

>Is the bow on the right 1/4 of the CRT visible in your photos?

It is only slightly visible in the close up photo. It is most noticeable when I have the scope set up per the calibration procedure for Y axis and Geometry adjustment. I will upload a photo of the display symptoms shortly.

According to the schematic for the horizontal amp, when the scope is set up in XY mode (as per the voltage measurement conditions) both plates should measure close to 52V. My 110V rail is 2V high, so it should measure 54V, but either way they should both be the same with the dot centered. Left plate measures 56.7V and Right plate measures 54.3V.
The horizontal position control is off-center to the right side of the display by approx 2 divisions.
Also, when I center the trace in a normal timebase setting and then switch it into XY, the dot is positioned that same 2 division to right offset.

>Are you referring to the start point of the A and B sweeps not being
>exactly aligned?

>The alignment depends on circuit tolerances and there may be no
>adjustment for it. At high sweep speeds, it is normal for the start
>of the sweep to creep to the right somewhat.

>I can probably suggest where it can be trimmed out if we determine
>that there is no actual fault.

Yes, I am referring to the A and B sweeps not being aligned. My other 468 doesn't have this problem at any timebase settings. (That one needs more work than the one being discussed.)

What really bothers me about it, and also has me slightly confused, is how to properly adjust the sweep start and sweep cal settings when taking this problem into account.

As per the horizontal cal procedure (it's the first step in this section):
-Set timebase A to 1ms and B to 5us
-Set delay time to 1.00
-Input 1ms time markers
-Adjust so the pulse displayed on B sweep starts at the beginning of the sweep & start of 2nd time marker from A sweep display**

The pulse on B sweep is not displayed if I set it to where I believe it should be - which is coinciding with the start of A sweep (which is the first time marker)
If I don't have it set exactly there, won't B sweep end up being out of tolerance?

I suppose I'll have to go through the waveforms again now that I have a digital scope and see if everything syncs up with the sync pulse, A and/or B sweep start, and blanking/unblanking. When I had checked them with my 465, everything appeared to be correct. Some waveforms just had minor differences in their voltage levels when compared against the manual spec, but seemed OK when compared against the other 468.

I definitely want to fix this and get them aligned. I guess I'm a bit OCD...

I just have a couple things to do and then I can get another picture or two uploaded, then do some waveform checking.

Re: Tek 7854 Info, Repair, Restore

 

You would not need the 7S11 at all but using the 7S12 as a sampling
sweep requires the S-53 Trigger Recognizer head which is shown in the
photo. This configuration gives roughly the capability of a 7T11
without the random sampling capability so a delay line would be needed
to see the triggering edge.

I think the delay line is more rare and expensive than a 7S14 which is
why I recommended the later. The 7T11 and 7T11A do away with needing
the delay line as well because of their random sampling capability but
are more difficult to use than a 7S14.

On 24 Feb 2016 15:26:27 -0800, you wrote:

Would it be possible to use a 7S12 as the timebase for a 7S11 in order to calibrate a 106 square wave gen? If so, would I need the 7M11 delay line?

I got the idea from one of Peter's Tekwiki images.

http://w140.com/tekwiki/wiki/File:7s12-7s11-1ghz-store.jpg http://w140.com/tekwiki/wiki/File:7s12-7s11-1ghz-store.jpg

Re: Need Help Fixing A Couple of 2445 Scopes

Michael
 

Hi,

I haven't seen a 2445, but I think it is pretty much like a 2465. The 4-pin
connector does indeed connect to the back of the GPIB board.

I think that the other connector goes to the power supply board A2A1. There
are two connectors that come up from the bottom of the case from the main
board. They have different pin spacing and are keyed. They connect pretty much
side by side to the A2A1 board.

There are some photos on the eevblog forum from my teardown of my 2465BCT in
the category "Test Equipment", topic: "Tektronix 2465B oscilloscope teardown".
The url is
http://www.eevblog.com/forum/testgear/tektronix-2465b-oscilloscope-teardown/550/
which contains the photos of some of my teardown. Part of that is pictures of
how the 4-pin connector is connected and pictures of the inside after the A3 /
A2A2 boards have been removed. You can see the large white connector coming up
from the bottom. The wires go inside the metal post to keep the options from
pinching them and the two connectors that come up from the bottom connect to
the A2A1 board.

You also have the fan power line that connects to the feed through capacitor
on the back, near the fan and the processor board.

There are four power wires. The two on the bottom go from the 115/230 switch
to the bottom two lugs on the A2A1 board. The two from the fuse holder go to
the top two lugs. The wire coming out of the end of the fuse goes to the lug
on the right (facing the A2A1 board), and the other goes to the lug on the
left. That doesn't quite match up with the schematic, but that is the way mine
was wired and it works. You have to be careful, those power wires are
difficult to get in place with no working room (loosen the back panel a bit
will help). It is easy to damage the fuse holder. I broke mine, but super glue
fixed it. There is also a ground wire from the A2A1 board that connects to the
back of the case.


Mike

Here's the problem. There are more insides, inside since this scope has
the GPIB Option, the problem is that I don't know where all of the wires go.
I think I got all but one cable plugged in in the right places, but I have
one end of one cable left, and I can't figure out where it goes.


The four conductor cable (all white wires) from the mode light panel
above the CRT, Does it plug into the four conductor terminal down low on the solder side of the GPIB board?


The cable that really has me stuck is a (seven?) single row conductor
cable with all white wires. One end seems to go on the Expansion
Motherboard that fits inverted on the top of the scope chassis, next to a 34
ribbon connector cable that goes to the A5 Control Board. Where does the
other end of this cable go? I can't seem to see any open plugs where it would fit.

Re: Tek 7854 Info, Repair, Restore

Brian Bloom
 

Would it be possible to use a 7S12 as the timebase for a 7S11 in order to calibrate a 106 square wave gen? If so, would I need the 7M11 delay line?

I got the idea from one of Peter's Tekwiki images.

http://w140.com/tekwiki/wiki/File:7s12-7s11-1ghz-store.jpg http://w140.com/tekwiki/wiki/File:7s12-7s11-1ghz-store.jpg

Re: 468 sweep offset issue

 

On 23 Feb 2016 19:13:28 -0800, you wrote:

I have been slowly working on getting this 468 fixed, back into spec, and calibrated.
Physically, it is mint. There's no damage anywhere.

I had to replace 3 of the PSU capacitors: the 55V, the 5V, and the -8V.
In the time where I hadn't the slightest clue what I was doing, I replaced lots of parts that I didn't need to - It has all new capacitors. New tantalums, new lytics, new poly HV caps... even new ceramics. I was very, very careful to make sure that I used the correct values for everything - and not to mix anything up.

There are still a couple of things left to resolve:

- There is a voltage offset between the horizontal deflection plates, which I believe is causing the vertical elements of the traces on the far right 1/4 of the CRT to have a slight bow to them. The Y axis and Geometry adjustments are not able to resolve this. I have not yet tracked down the source of the issue here.
I am not sure what you mean by voltage offset. With no sweep, there
is always a voltage offset because the blanked beam is located at the
left side of the CRT.

Is the bow on the right 1/4 of the CRT visible in your photos?

- The B sweep and A sweep do not sync at the start of the sweep. The sync pulse is correct. I have checked all of the waveforms numerous times trying to isolate the problem, but I believe this is a problem in the timebase section (according to "Tek: troubleshooting your oscilloscope") - making it a royal pain for a beginner like me to track down.
**This is the issue that is giving me all of the trouble**
Are you referring to the start point of the A and B sweeps not being
exactly aligned?

The alignment depends on circuit tolerances and there may be no
adjustment for it. At high sweep speeds, it is normal for the start
of the sweep to creep to the right somewhat.

I can probably suggest where it can be trimmed out if we determine
that there is no actual fault.

I have swapped out the trigger board and also the timebase board in an effort to at least isolate the fault to a specific block. The problem must reside on the main board. My guess is that it's going to be in the sweep logic circuitry.

I have been using the "Tektronix: troubleshooting your oscilloscope" book. I have read the theory of operation for this scope a couple of times. I have even read the circuit description section of my 465 manual to try and get a better understanding of the basic functionality of these scopes.

I'm hoping that I will have an easier time troubleshooting since I bought a new digital scope.
I'm confident that I'll be able to track down the problem with the horizontal amp , but this sweep start offset is driving me nuts and I just cannot figure it out! Will someone please point me in the right direction?

Pics of the problem:
https://groups.yahoo.com/neo/groups/TekScopes/photos/albums/1461836945/lightbox/1384398865?orderBy=ordinal&sortOrder=asc&photoFilter=ALL https://groups.yahoo.com/neo/groups/TekScopes/photos/albums/1461836945/lightbox/1384398865?orderBy=ordinal&sortOrder=asc&photoFilter=ALL

Re: 7904 - Very Dim Trace

 

On 23 Feb 2016 20:08:08 -0800, you wrote:

Small update:

I went through the Service Manual's Z-axis DC Levels Procedure (pertaining to R1757, R1810, and R1817). All went well. Or at least I had no trouble adjusting it to spec. The dim display persists. Focus is good. Deflection is not affected. (all as noted earlier in this thread)

Again, I measured the cathode at -3001V, and the control grid at -3001 to -3050, depending on the intensity controls.

I don't see how this can have anything to do with the DC restoration circuits. Though if someone can explain how that's possible, I have the caps and diodes in-hand to rebuild it...
With these measurements I do not see how either.

One tiny clue, perhaps. On the fateful night when I last switched off the scope while it was working (with a bright display), I noticed a pretty bright glow immediately afterwards on the CRT face. I don't recall any more details, but it seemed a little odd, although I hadn't been using this scope long, so didn't think too much about it. Still... Hmm...
CRTs generate an afterglow even from picking up ambient room lighting.

I wonder if the CRT was damaged in some way. The control grid is not
like the grid of a normal tube so I cannot see how it could be
damaged.

What about voltages to the other CRT elements which go through P1720
including the -50 volt and ground connections? Are they correct?

Maybe there is enough variation in CRT performance with different PDA
voltages to explain it. My 7904 using a 12 kilovolt PDA may be
atypical.

Since the only diagnosed problem that can be fixed so far is the PDA,
that may be the best option.

Re: PG506 mod

 

It might be worthwhile to go through the parts list and mark on the
schematic exactly which parts apply to the first version of the early
PG506 and which parts apply to the last version of the early PG506 to
get two different schematics instead of one merged one.

That may reveal the reason for any performance differences. As the
schematic is now, it is difficult to tell what is even going on since
it is effectively wrong for all versions.

On 23 Feb 2016 03:12:43 -0800, you wrote:

Thanks, guys. I now understand that this is stock and only depends on serial number.
Will post mine later.

Nonetheless I'm wondering why the risetime of the standard pulse was noticeably better on the unit with the large heat sink (don't know whether it has sth. to do with it, though)

Re: Need Help - Tektronix 7844 Dual Beam Scope

 

On Tue, 23 Feb 2016 15:34:34 -0500, you wrote:

So both beams have the same intensity problems?
It appears so. I feed the Calibrator to both inputs of a 7A26 Vertical
module (left slot). BEAM 1 and 2 are set to LEFT. Using the Vertical
positioning on the vertical module, I can moving either beam on and off
screen. They both appear to be the correct display (Vertical Gain and Time
Base working normally) but the brightness is very high and I have no control
over either BEAM INTENSITY or FOCUS ON EITHER CHANNEL.
The beams have completely separate intensity and focus circuits so I
would look for a problem which could affect both.

Excessive beam current should cause the power supply to reset instead
of just affecting the 17 volt output.
I was just monitoring the 17 volt line - others may change as well. This
effects seems intermittent as I just tried to monitor the other supply
voltages under the same conditions and the power supply was not affected.
I'm cautious about leaving the display on very long - don't want to burn the
CRT or possibly fry the power supply.
Are all of the regulated power supply outputs correct?

Those amplifier outputs control the focus and not the intensity.
TP1186 and TP2086 shown on schematic 14 are the z-axis outputs which
control intensity.
INTENSITY controls seem to connect to GRID 2 - I'm missing something here -
can you give me an idea how this circuit works or where I might look it up?
I thought I remembered an old Tektronix book on CRT design but can't find
it.
There is one intensity control element and one focus control element
per beam. The signal from each intensity control potentiometer splits
to drive both the z-axis amplifier and the focus amplifier for one
beam.

I checked TP 1186 BEAM 1 (Card A21) - adjusting BEAM INTENSITY - voltage is
+9.75 CCW to + 68.5 Volts CW. So far I have not been able to get as BEAM 2
card for TP2086.
So the focus amplifier output voltages are correct and at least one of
the z-axis amplifier output voltages is correct.

Check that connectors P2390 and P2490 shown at the bottom left corner
of schematic 15 are good.

Are the grid bias controls R1180 and R2080 working correctly? Do they
do anything when the intensity is turned fully CCW? They are shown at
the bottom left corner of schematic 15.

Re: Packing a scope for shipping

S. Truong <sammy.truong@...>
 

Hi all, to add to some of the sound advice shared so far, I thought I'd
pass along these words directly from the horse, transcribed from my 2465
Service and Instruction manual:

REPACKAGING FOR SHIPMENT

If this instrument is to be shipped by commercial transportation, it is
recommended that it be packaged in the original manner. The carton and
packaging material in which your instrument was shipped to you should be
saved and used for this purpose.

If the original packaging is unfit for use or is not available, repackage
the instrument as follows:

1. Obtain a corrugated cardboard shipping carton having inside dimensions
at least six inches greater than the instrument dimensions and having a
carton test strength of at least 275 pounds.

2. If the instrument is to be shipped to a Tektronix Service Center for
service or repair, attach a tag to the instrument showing the following:
owner of the instrument (with address), the name of the person at your firm
who can be contacted, complete instrument type and serial number, and a
description of the service required.

3. Wrap the instrument with polyethylene sheeting or equivalent to protect
the outside finish and prevent entry of packing materials into the
instrument.

4. Cushion the instrument on all sides by tightly packing dunnage or
urethane foam between the carton and the instrument, allowing three inches
on each side.

5. Seal the carton with shipping tape or with an industrial stapler.

6. Mark the address of the Tektronix Service Center and your return address
on the carton in one or more prominent locations.


Best,
Sammy

On Wed, Feb 24, 2016 at 6:18 AM, Tom Gardner tggzzz@... [TekScopes] <
TekScopes@...> wrote:



Thanks to everybody for their thoughtful and practical tips.



--
--
sammy.truong@...

Re: Reinserting CRT into a 465 chassis

Tom Gardner
 

On 24/02/16 13:24, Malcolm Hunter malcolm.r.hunter@... [TekScopes] wrote:

On 24 February 2016 at 13:13, Tom Gardner tggzzz@... [TekScopes] <
TekScopes@...> wrote:

Did you manage to find a replacement CRT then?
Hopefully yes, and from the source you most helpfully suggested. But since
it
isn't yet in my possession, I'm not "counting my CRTs until they are
hatched" :)
​Here's hoping it won't be hatched in transit :)
A major advantage of this source is that I'm picking it up in person (date TBA).
If it hatches, it'll be my fault!

Re: Reinserting CRT into a 465 chassis

Malcolm Hunter
 

On 24 February 2016 at 13:13, Tom Gardner tggzzz@... [TekScopes] <
TekScopes@...> wrote:

Did you manage to find a replacement CRT then?
Hopefully yes, and from the source you most helpfully suggested. But since
it
isn't yet in my possession, I'm not "counting my CRTs until they are
hatched" :)
​Here's hoping it won't be hatched in transit :)

Malcolm​


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

Re: Reinserting CRT into a 465 chassis

Tom Gardner
 

On 24/02/16 12:53, Malcolm Hunter malcolm.r.hunter@... [TekScopes] wrote:

On 24 February 2016 at 12:32, Tom Gardner tggzzz@... [TekScopes] <
TekScopes@...> wrote:

​I just used my Lindstrom needle-nose pliers when I took the base board
off
a few times.​ I've been told forceps are quite good for this too:

http://www.amazon.com/5-5-KELLY-Hemostat-FORCEPS-Straight/dp/B000QWK174
I'm hoping it won't be necessary to remove the interface board; too may
connections to get wrong. (Me a pessimist? Shurely shome mishtake!)

It is hopeful that those forceps are similar in concept to my "tweezers"
like:

http://www.amazon.com/TWEEZER-CROSS-TWEEZERS-CLOSING-NOVELTOOLS/dp/B011ABLEE8
​If you can get a decent grip with those, you should be okay. You need a
firm grip so they don't slip when you're pushing the pins back on.
Yes; the grip is unclear at the moment. Forceps would be better in that regard.

No, you won't need to remove the board if you're changing the CRT - I did
so to get to the bridge rectifier connections, though even that wasn't
really necessary. Did you manage to find a replacement CRT then?
Hopefully yes, and from the source you most helpfully suggested. But since it
isn't yet in my possession, I'm not "counting my CRTs until they are hatched" :)

Thanks.



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

Re: Reinserting CRT into a 465 chassis

Malcolm Hunter
 

On 24 February 2016 at 12:32, Tom Gardner tggzzz@... [TekScopes] <
TekScopes@...> wrote:

​I just used my Lindstrom needle-nose pliers when I took the base board
off
a few times.​ I've been told forceps are quite good for this too:

http://www.amazon.com/5-5-KELLY-Hemostat-FORCEPS-Straight/dp/B000QWK174
I'm hoping it won't be necessary to remove the interface board; too may
connections to get wrong. (Me a pessimist? Shurely shome mishtake!)

It is hopeful that those forceps are similar in concept to my "tweezers"
like:

http://www.amazon.com/TWEEZER-CROSS-TWEEZERS-CLOSING-NOVELTOOLS/dp/B011ABLEE8
​If you can get a decent grip with those, you should be okay. You need a
firm grip so they don't slip when you're pushing the pins back on.

No, you won't need to remove the board if you're changing the CRT - I did
so to get to the bridge rectifier connections, though even that wasn't
really necessary. Did you manage to find a replacement CRT then?

Malcolm​

Re: Reinserting CRT into a 465 chassis

Tom Gardner
 

On 24/02/16 11:46, Malcolm Hunter malcolm.r.hunter@... [TekScopes] wrote:

On 24 February 2016 at 11:38, tggzzz@... [TekScopes] <
TekScopes@...> wrote:

Of particular concern are the wires to the horizontal deflection plates on
the CRT's neck. Removing the wires to the horizontal deflection plates on
the CRT's neck is probably not problem. If nothing else, simply pulling on
the wires to the interface board will probably slip the wires off the CRT.
Replacing them looks trickier, since they are about 5cm down inside a 1.5cm
hole, and my fingers aren't that small!

So, are there any practical techniques that aren't mentioned in the
manual?
Are long tweezers sufficient?
Is it sensible/possible to desolder the wires from the PCB, attach them to
new CRT before it is reinserted in the chassis, tie a thread to the wires,
feed the thread through the chassis and PCB holes, reinsert the CRT in the
chassis using the thread to guide the wires, and finally resolder the wires
to the PCB.
​I just used my Lindstrom needle-nose pliers when I took the base board off
a few times.​ I've been told forceps are quite good for this too:

http://www.amazon.com/5-5-KELLY-Hemostat-FORCEPS-Straight/dp/B000QWK174
I'm hoping it won't be necessary to remove the interface board; too may
connections to get wrong. (Me a pessimist? Shurely shome mishtake!)

It is hopeful that those forceps are similar in concept to my "tweezers" like:
http://www.amazon.com/TWEEZER-CROSS-TWEEZERS-CLOSING-NOVELTOOLS/dp/B011ABLEE8

Thanks.


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