Date   
P6041 Cables

Richard Solomon
 

I ran across two cables, about
3.5 feet long. BNC on one end
and what looks like a push-on
SMA on the other.
Marked Tektronix 010-164 and
P6041 Zo=50 ohm.

No need for them, will swap them
off for a decent 500 MHz Tek Probe.

Anyone interested ?

73, Dick, W1KSZ

Re: Tek blank box the size of a half rack 620 monitor available

John Griessen
 

On 1/28/20 9:17 AM, Oz-in-DFW wrote:
What country is it in?
Sorry, it's claimed. I promise next time to list things just like they were going in test equip for sale,
with location, condition, price, payment methods...

I just thought this one was not going to get interest and be scrapped.

It's USA TX $25 shipped for parts clean pay by check or extra 4%

But, that's going to be for next time -- David Holland claimed it.

Re: Tek blank box the size of a half rack 620 monitor available

Oz-in-DFW
 

What country is it in? What are you asking for it?

Re: TDS784C

Siggi
 

On Tue, Jan 28, 2020 at 8:39 AM JJ <jajustin@...> wrote:

You need to be concerned with the NVRAM chips - DS1486 clock chip and the
DS1650/DS1250. They have internal batteries that hold the calibration
constants and options info.
It's my understanding that the calibration constants are stored in EEPROM
on the acquisition board. There's no reason to worry about the options, as
it's easy enough to restore those with GPIB or other means.

Re: Guernsey Island 2445

Chuck Harris
 

Bite me!

-Chuck Harris

Colin Herbert via Groups.Io wrote:

Chuck, speaking as a Brit, can you please stop spelling it "Gurnsey". I don't think you would like it much if I referred to the US city as "Filadelfia" would you? I should maybe point out that in UK English, "gurning" is a term for making silly faces.

While I am in this mood, The Heerenveen Tek factory was in Holland, but "Holland" is a term for a part of the Netherlands, not the name of the whole country. [grumpy mode off]

Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: 27 January 2020 17:14
To: TekScopes@groups.io
Subject: Re: [TekScopes] Guernsey Island 2445

Hi Raymond,

Very well, I must have misunderstood what I was told by
a former tektronix engineer from Gurnsey, 40 years ago.

I met him at one of my customer's sites, he was working
for a division of my customer's company in Guernsey, and
was TDY here in the states for training.

He noticed my brand new 2465, and clearly was itching
to talk with me about it. He was involved in the design
when he was at Tek Guernsey. He looked at my scope's serial
number to see where mine was made, and that brought on
a discussion of the serial numbers, factory of origin,
and revisions.

40 years is a long time, and I am somewhat surprised that
I remember the meeting at all. It was just a transient
thing one morning.

In the 40 years since, I have seen only one example of
a scope from any tektronix overseas factory, other than
Japan, and that was a 468 that I own that came from Holland.

I own two 468's, one from Holland, and one from Beaverton.

Both appear to be identical in board revisions, and software
revisions...

One is B014XXX, and the other is 705XXX

To my eye, it looks like they relate by subtracting the
universal Beaverton "zero" serial number (B010101) from the
Beaverton unit... but my sample set is too small.

Tektronix isn't stupid enough to have not had a simple way
to connect the dots between the scopes that were made in
multiple countries.

-Chuck Harris

Raymond Domp Frank wrote:
On Sun, Jan 26, 2020 at 10:17 PM, Chuck Harris wrote:


The primary thing I was trying to relate is the last
5 digits determines which engineering change orders
apply to your instrument.
I'm pretty sure that's incorrect across serial numbers from different countries of manufacture, Chuck, but I'm happy to check and provide (dis)proof when I'm back in the lab...
Unless unwelcome signs of old age have set in, ISTR that's exactly what many of us (mostly non-US based) have had to deal with for years.
It is one unfortunate thing that I have never understood from Tek.

Raymond









Re: Guernsey Island 2445

Michael A. Terrell
 

None of mine start with a J:

305113
302234
302310
302903
These are Sony/Tektronix323 and 324 scopes.

On Mon, Jan 27, 2020 at 8:21 AM Charlie.c <ctconger@...> wrote:

To further thicken the plot I know that in the 80 s and later standard
numbering for all Beaverton made models began with B010100.
The first production unit made would carry that serial number. I was told
this was to confuse the competition so they would have difficulty tracking
how many units of a particular type had been made.
Not sure about the other countries. But al the Sony/TEK made stuff I ever
saw began with a J.



Re: TDS784C

Steve Hendrix
 

At 2020-01-28 09:00 AM, Jay Walling via Groups.Io wrote:


Make sure that it passes SPC from the utility menu - at least 10 times
with no failures.
Also run the full self test from the same utility menu.
I'll probably think of it right after I hit "send", but what does SPC stand for in this context?

Steve Hendrix

Re: TDS784C

 

Any other pointers, pitfalls, etc. from current or past users of this scope would be very welcome. I've seen it occasionally mentioned here, but maybe the relative lack of chatter suggests it's one of those instruments that just plain works.
Hi Steve,

Make sure that it passes SPC from the utility menu - at least 10 times with no failures.
Also run the full self test from the same utility menu.

Jay

Re: TEK514 needs new 5V4G tube

Trevor
 

Steve-
Looking at the schematic I downloaded for the 514, there are five capacitors in the power supply that are two section 20 micro-farad cans, and these all should be tested, reformed, or replaced.  A sensible approach for testing and reforming is to use a separate laboratory bench power supply with a current limiting series resistor.

Be careful with C210, as it has its outer aluminum can (which is the negative capacitor lead) connected to the +225 volts supply. This is common practice in Tek tube scopes, and the case of a capacitor at elevated potential is protected with an insulating blue paper or clear plastic sleeve.

Protective sleeves are also used with capacitors in the negative supply section, as with C216 where the positive capacitor lead is grounded.


Newer 500 series scopes typically have a thermal time delay relay, so the scope's plate voltages are delayed 30 seconds or so, allowing tube filaments to warmed up first. The 514 does not have a delay relay, but the 5V4 rectifiers, with their indirectly heated cathode will yield a desirable slow plate voltage ramp-up. Replacing the 5V4's with solid state rectifiers has some appeal, but note that the slow ramp-up will no longer occur.

Note also, there are three 5V4 tubes in parallel. Ideally, they should share the current equally, but if one tube is near end of life, the other two will need to work harder. Verifying that the three rectifiers are sharing the load equally presents a challenge. Perhaps your infrared thermometer would work. A tube tester would help, if you have access to one. A riskier approach is to remove just one 5V4 at a time, making two remaining rectifiers do the work of three, but just for brief testing. Observe the voltage on C212 to see how good the two installed 5V4s are.


Vacuum tubes typically have an area inside the glass envelope that is shiny and mirror like, which is the "getter flash". Faulty tubes can sometimes be identified by this flash being white, meaning the tube's vacuum has been compromised. You should visually compare the three 5V4s for other differences, such as sputtered metal debris. Test with a DVM for dead shorts too of course.

Work slowly and methodically, and not when tired. The power supply voltage are dangerous. Besides shock hazards, flying molten metal from accidental short circuits can cause eye injury.
Trevor

On Tuesday, January 28, 2020, 6:57:26 AM EST, David Holland <david.w.holland@...> wrote:

On Mon, Jan 27, 2020 at 10:05 PM Chuck Harris <cfharris@...> wrote:

A hack saw works fine too... if you are careful.
If you completely remove the cap (I usually do), a copper tubing
cutter works wonderfully....

One of these things:
https://www.harborfreight.com/tubing-cutter-40913.html   (Yeah, I
know, Harbor Freight, but they did have a convenient picture.)

David

Re: TDS784C

JJ
 

Hi Steve,

You need to be concerned with the NVRAM chips - DS1486 clock chip and the DS1650/DS1250. They have internal batteries that hold the calibration constants and options info. The batteries expiration date ended many years ago. So, if those chips haven't been changed, you need to attend to it. Many articles on backing those chips up using the GPIB interface, the internal disk drive, and other ways on this site and forum.tek.com. But, hopefully, someone swapped out the chips already.
Great scope - good luck, with it! I have a TDS754C.
Best,
John Justin

Re: Guernsey Island 2445

Colin Herbert
 

Chuck, speaking as a Brit, can you please stop spelling it "Gurnsey". I don't think you would like it much if I referred to the US city as "Filadelfia" would you? I should maybe point out that in UK English, "gurning" is a term for making silly faces.

While I am in this mood, The Heerenveen Tek factory was in Holland, but "Holland" is a term for a part of the Netherlands, not the name of the whole country. [grumpy mode off]

Colin.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Chuck Harris
Sent: 27 January 2020 17:14
To: TekScopes@groups.io
Subject: Re: [TekScopes] Guernsey Island 2445

Hi Raymond,

Very well, I must have misunderstood what I was told by
a former tektronix engineer from Gurnsey, 40 years ago.

I met him at one of my customer's sites, he was working
for a division of my customer's company in Guernsey, and
was TDY here in the states for training.

He noticed my brand new 2465, and clearly was itching
to talk with me about it. He was involved in the design
when he was at Tek Guernsey. He looked at my scope's serial
number to see where mine was made, and that brought on
a discussion of the serial numbers, factory of origin,
and revisions.

40 years is a long time, and I am somewhat surprised that
I remember the meeting at all. It was just a transient
thing one morning.

In the 40 years since, I have seen only one example of
a scope from any tektronix overseas factory, other than
Japan, and that was a 468 that I own that came from Holland.

I own two 468's, one from Holland, and one from Beaverton.

Both appear to be identical in board revisions, and software
revisions...

One is B014XXX, and the other is 705XXX

To my eye, it looks like they relate by subtracting the
universal Beaverton "zero" serial number (B010101) from the
Beaverton unit... but my sample set is too small.

Tektronix isn't stupid enough to have not had a simple way
to connect the dots between the scopes that were made in
multiple countries.

-Chuck Harris

Raymond Domp Frank wrote:
On Sun, Jan 26, 2020 at 10:17 PM, Chuck Harris wrote:


The primary thing I was trying to relate is the last
5 digits determines which engineering change orders
apply to your instrument.
I'm pretty sure that's incorrect across serial numbers from different countries of manufacture, Chuck, but I'm happy to check and provide (dis)proof when I'm back in the lab...
Unless unwelcome signs of old age have set in, ISTR that's exactly what many of us (mostly non-US based) have had to deal with for years.
It is one unfortunate thing that I have never understood from Tek.

Raymond



TDS784C

Steve Hendrix
 

I didn't research this as well as I might have, because I really didn't expect to get it. I made a fairly low offer on eBay for a TDS784C, fully expecting it to be rejected. Pleasant surprise when it was accepted. The unit arrived last Wednesday and I've been so swamped with work, family, and volunteer work that I just finally got it out of the box yesterday. Very nice unit, exactly as advertised, and appears to be fully working. It's physically quite a bit bigger than I anticipated, so I need to do some long-overdue housecleaning in the lab to make room for it.

It came as stated with no cables or accessories. Power cords I have in abundance. I have some 100 MHz scope probes available, but of course those won't let me use the full 1 GHz bandwidth. I plan to use another of my KISS-488 interfaces for screenshots and PC control, so that's covered. I have the crippleware version of WaveStar that came with my TDS220 so will try that with this unit. Can anyone here point me to a good reliable source of 1 GHz rated probes (that won't cost more than I paid for the scope!).

Any other pointers, pitfalls, etc. from current or past users of this scope would be very welcome. I've seen it occasionally mentioned here, but maybe the relative lack of chatter suggests it's one of those instruments that just plain works.

Thanks for reading!

Steve Hendrix

Re: TEK514 needs new 5V4G tube

David Holland
 

On Mon, Jan 27, 2020 at 10:05 PM Chuck Harris <cfharris@...> wrote:

A hack saw works fine too... if you are careful.
If you completely remove the cap (I usually do), a copper tubing
cutter works wonderfully....

One of these things:
https://www.harborfreight.com/tubing-cutter-40913.html (Yeah, I
know, Harbor Freight, but they did have a convenient picture.)

David

AWG2005/2020/2021/2041 Parts?

Mlynch001
 

Does anyone in the group have any spares for the AWG2005/2020/2021/2041 Series Waveform Generators?

Specifically:

Low Voltage Power Supply 620-0058-02 or 620-0065-00

Or

FPP Board (A7) Option 09 671-3179-00

Looking for either or both that are in need of a good home.

In addition: If someone has a Low Voltage Power Supply Schematic for this unit, which they could share, that would be excellent. I would like to try to attempt to repair the LVPS in this unit if possible.
--
Michael Lynch
Dardanelle, AR

Re: Tektronix op amp plugins (Type O or AM501) have you used one?

Tim Phillips
 

from Tim P (UK)
J. Hunt asks about interesting uses for Type 'O's

I put together a setup with a type 1A1 in a 547, and a Type 'O' in a 132.
The ch1 out signal from the 1A1 was input to the Type 'O' , transformed in
various ways, and from there input to ch2. on the 1A1.
After getting it all to trigger nicely, I had a 'before & after' display.

I also had two Type 'O's in a 536 X/Y 'scope - tried playing with some
'Spirograph (tm)' - like displays using the Log Adapter.
Tim



On Tue, 28 Jan 2020 at 04:30, J Hunt via Groups.Io <jmailhunt=
yahoo.com@groups.io> wrote:

Glenn's posting (attached below) about his Type O op amp plugin got me
thinking about the AM501 op plugin I had in my lab. I used it only once
for a quick setup when I needed a higher voltage and current than I could
get from an IC opamp. Otherwise it stayed on the shelf.

Have you used a Type O or an AM501 for anything interesting?


********************************************************************************
Specs and links from tekwiki:

AM501 Operational Amplifier (TM500 plugin)
5MHz GBW DC Gain 10,000 Input Bias Current < 0.5nA
Output +- 40V, +- 50mA Available 1974 - ?
http://w140.com/tekwiki/wiki/AM501

Type O Dual Opamp
Letter-series plugin for 500 series scopes or could be a standalone
instrument if
plugged into external power supplies like the 132. Available 1962-73.

15MHz GBW DC Gain 2500 Grid Current (Input Bias Current) < 0.5nA
Output +- 50V, +- 5mA
Tube based design (plus a couple of transistors).
http://w140.com/tekwiki/wiki/O

The manual section of that web page has a link to "Tektronix Opamps and
Their Applications" from 1965 which has 70 pages of op amp theory and
interesting measurement and analog computer era applications. How about
putting a triode in the feedback circuit to create a square root function?
Or use the op amp to measure the voltage coefficient of a capacitor?
Pretty cool.

John Hunt
Portland, OR


********************************************************************************
4a. Re: Type O plugin with Power Supply
From: Albert Otten
Date: Mon, 27 Jan 2020 08:56:06 PST
On Mon, Jan 27, 2020 at 03:19 AM, Glenn Little wrote:


Link to picture.
Can take more if interested.

https://groups.io/g/TekScopes/photo/239601/0?p=Created,,,20,2,0,0
It would be interesting to see what the difference with an ordinary Type
132 are.
Albert



5D10 + LEFT plugin working in 5441 (5440,5403)

p mc
 

Hello TekScopes! Thank you all for aiding and abetting. Here's a tiny bit of giving back.

PHOTOS: https://groups.io/g/TekScopes/album?id=239656

The 5D10 Waveform Digitizer plugin, essentially a 1MS/s DSO, gets some credit for keeping the 5000 series oscopes interesting[1]. While a 5D10 can digitize one or two channels from another plugin, only the "slow" 51xx scopes supported that capability[2]. 5000-series docent Christian Weagle tried to adapt a "fast" 5440 with initial success that didn't pan out[3]. I fell down this rabbit hole and eventually climbed out with a good result for my 5441. The same should work for a 5440 also - i.e. 5403 mainframes.

To enable LEFT plugin access for a 5D10 in a 5403/5440/5441 scope:
add three connections between plugin connectors[4] on the interface board.
1. left A13 <---> center A17
2. left B13 <---> center A16
3. horizontal A19 <---> adjacent DIP14 7473 pin 6

The two left <---> center connections give the 5D10 access to the differential signal from the left plugin bay. That alone allows acquisition of a _single_ LEFT channel when the left plugin DISPLAY switch is _OFF_.[5] A pair of 10cm F-F "dupont" jumpers made this connection trivially and reversibly.[6]

The horizontal A19 <---> 7473 pin 6 connection lets the 5D10 keep control of the display when the left plugin DISPLAY switch is ON[7]. Then the 5D10 can cycle the channel select logic to sample both channels from a dual channel plugin without chopping up the display.

Mr. Weagle offered a "reasonable guess" that Tek didn't support this configuration because adding extra load to the signal path would blunt high frequency response of the left plugin bay in normal operation of the faster 54xx scopes and later attributed disappointing results to hitting that problem hard[3]. After much pondering how to deal with that, I eventually got around to trying it to assess the magnitude of the problem and found… no problem. By not-very-careful measurement, the added load attenuates a 6div 50MHz signal by a fraction of a trace width at most and a 100MHz signal by approximately not much[8]. The mild loss of far-above-spec bandwidth from the left bay is good to know but I won't worry about it.

Beware. While the added jumpers themselves didn't bog down a 54xx-speed left plugin, Tek cautions that a horizontal plugin in the center bay certainly will. The manual says "nondestructively". The manual also only contemplates plugins compatible with 5100 series scopes. I haven't tried to work out if any of the faster plugins could be more vulnerable.

The procedure for modifying elder 51xx mainframes advises adding some resistors. 54xx scopes already have them.

Schematics for 5116 and 5111A (after the first 206 units) show ferrite beads on the left <---> center connections. Considering that no ferrites are advised for updating older scopes and Tek apparently shipped a couple hundred 5111As without them, I suppose that their potential benefit is less than compelling.

I have an Option 1 scope without the readout board. That allowed easy access to the back of the plugin interface board. For scopes with readout, removing the readout board may be helpful or necessary. The manual for installing the Option 3 custom readout wiring describes how to pull the readout board from a desktop scope by partially separating the back ends of the display and mainframe modules.[9]

Doing this with a 5444 might be as simple as adding the two signal jumpers and turning the left beam intensity down. ?.

Working this out involved some side trips that might become future posts, but that will be for another day.

Please tell us if you verify this working in another 54xx scope.

pmc

==END==
===========
=notes=

[1] Ironically lauded for superior slowness
https://groups.io/g/TekScopes/message/131488
https://groups.io/g/TekScopes/message/114295
https://groups.io/g/TekScopes/message/82688 but 3 traces vs "dual trace"
(And the très spécial 5116+5D10 "Three Color, High Resolution Digital Storage Display"! http://w140.com/tekwiki/images/0/0a/5D10tb.jpg but that's its own thing)

[2] Older 51xx scopes require modification. See pages 4-21,23 of the service manual (ToC is rwong). This provides a jumping-off point for working out what to do with 54xx scopes. Manuals available here: http://w140.com/tekwiki/wiki/5D10

[3] AKA tertiary_42, i9t.net
https://groups.io/g/TekScopes/message/24563
https://groups.io/g/TekScopes/message/44217
https://groups.io/g/TekScopes/message/46276
Mr. Weagle stopped posting without comment after April 2010. Does anyone here know of his well-being?

[4] Aargh with naming plugin bays. "Left" & "horizontal" are unambiguous if not orthogonal. But "right vertical" vs "center" vs "left half of 5D10" per context complicate naming the one between the other two. "Center" clashes with Tek's left/right/horizontal nomenclature but depends less on context.

[5] May or may not work with DISPLAY=ON depending on indeterminate state of the channel switch logic. This may be part of why Mr. Weagle reported initial success then not.

[6] Like this:
https://web.archive.org/web/20190629041238/https://www.aliexpress.com/item/32822646871.html
The plugin connector pins are larger than 25mil so "Dupont" F pins need a firm push to fit over them. They might not fit securely on 25mil pins anymore but I don't expect to care. Fitting them with clearance under a readout board may require a little attention.

[7] The 7473 is dual flip-flop IC U780 in the interface board schematic. One ff toggles which channel dual channel plugins send to the mainframe and also clocks the other ff to alternately send left or "right vertical"/center plugin signals to the display when both vertical plugins set DISPLAY=ON (which the 5D10 does always). The schematic doesn't show unused pin 6 which is the CLR pin (CLeaR i.e. asynchronously RESET) for the plugin select ff. The 5D10 pulls horizontal plugin pin A19 low which in later 51xx mainframes asserts the asynchronous PRESET input of the 74113 type plugin select ff used in those instruments. While the 7473 ffs have no PRESET input, the 5403 logic is arranged differently so that asserting CLR does the right thing.

[8] To get some idea where trouble starts, I first clipped a pair of ~1foot 24awg silicone insulated leads to the A/B13 pins at the back of the interface board. Twisting them together cut a 50MHz signal by about 10% amplitude and 100MHz by about 50%, both roughly estimated. Laying the leads together without twisting had discernible but small effect at 50MHz and more noticeable but still small effect at 100MHz, no quantitative estimate attempted. So don't use foot-long jumpers.

[9] http://www.i9t.net/5400-opt03/040-0873-01.pdf
Made more widely known by Christian Weagle: "The instructions give a good procedure to get [the readout board] out. I'd recommend following their advice about raising the rear of the display, by the way."
http://www.i9t.net/5000_scopes.html

Re: TEK514 needs new 5V4G tube

Dave Trainor
 

I have had luck then the mallory¹s I have done this with had black tar in
the bottom, with the aluminum foil tape probably point welded to it, then
the solid wet cap above, once all cleaned out I had the pins that were in
tar to protect them able to be soldered to.

It all cleaned out easily. But make sure you leave a lip at the bottom of
the case when you cut so you got a upper and lower area for the final
sealing tape to stick to to reassemble. Cut too close to the bottom and no
place for that end to stick, so I usually stay about 1/2 inch up.

If there is not a term, punching a hole thru for a wire for the new cap is
sure the way to go.

I think you can get longer rated hours in the snap in variety vs a redial,
if I can actually believe the specs as published. Far as I know there are
none made anywhere but Asia now, no matter the name brand of manufacturer.
I try to find the ones with the longest listed expected lifetime hours on
Mouser. And a name that I have at least heard of, Panasonic, Sprague,
Vishay etc.

Loved the explanation from the guy that uses a lathe, and 3d printing and
literally makes a new sealed can, that dude, is dedication in restoration.
Beyond what I could do but - respect your way sir.

73 - Dave N8ZFM


On 1/27/20, 10:04 PM, "TekScopes@groups.io on behalf of Chuck Harris"
<TekScopes@groups.io on behalf of cfharris@...> wrote:

I do it much the same way. Copper, or steel wouldn't last
very long in the electrolyte before it corroded away, so it
is only aluminum in the can.

Tektronix op amp plugins (Type O or AM501) have you used one?

J Hunt
 

Glenn's posting (attached below) about his Type O op amp plugin got me thinking about the AM501 op plugin I had in my lab. I used it only once for a quick setup when I needed a higher voltage and current than I could get from an IC opamp. Otherwise it stayed on the shelf.

Have you used a Type O or an AM501 for anything interesting?

********************************************************************************
Specs and links from tekwiki:

AM501 Operational Amplifier (TM500 plugin)
5MHz GBW DC Gain 10,000 Input Bias Current < 0.5nA
Output +- 40V, +- 50mA Available 1974 - ?
http://w140.com/tekwiki/wiki/AM501

Type O Dual Opamp
Letter-series plugin for 500 series scopes or could be a standalone instrument if
plugged into external power supplies like the 132. Available 1962-73.

15MHz GBW DC Gain 2500 Grid Current (Input Bias Current) < 0.5nA
Output +- 50V, +- 5mA
Tube based design (plus a couple of transistors).
http://w140.com/tekwiki/wiki/O

The manual section of that web page has a link to "Tektronix Opamps and Their Applications" from 1965 which has 70 pages of op amp theory and interesting measurement and analog computer era applications. How about putting a triode in the feedback circuit to create a square root function? Or use the op amp to measure the voltage coefficient of a capacitor? Pretty cool.

John Hunt
Portland, OR

********************************************************************************
4a. Re: Type O plugin with Power Supply
From: Albert Otten
Date: Mon, 27 Jan 2020 08:56:06 PST

On Mon, Jan 27, 2020 at 03:19 AM, Glenn Little wrote:


Link to picture.
Can take more if interested.

https://groups.io/g/TekScopes/photo/239601/0?p=Created,,,20,2,0,0
It would be interesting to see what the difference with an ordinary Type 132 are.
Albert

Re: TEK514 needs new 5V4G tube

Mlynch001
 

I restore those can type caps by putting them in a lathe, cut the rolled edge off, remove the guts, save the metal grounding ring and solder lug ring from the old cap, clean out the inside, 3D print a spacer to hold the required radial cap centered with airspace around the outside (this keeps the new cap from flopping around inside the can), 3D print a bottom plate of suitable dimensions to hold the old solder lug, place the new cap inside with the leads protruding from the appropriate holes, re-roll the lower edge of the can to secure the assembly and then solder the leads. Makes a perfect OEM original looking replacement part with a modern cap inside.

--
Michael Lynch
Dardanelle, AR

Re: TEK514 needs new 5V4G tube

Chuck Harris
 

I do it much the same way. Copper, or steel wouldn't last
very long in the electrolyte before it corroded away, so it
is only aluminum in the can.

A hack saw works fine too... if you are careful.

-Chuck Harris

David Holland wrote:

Not too bad. They're not liquid. More like damp. Stinky too. There may
be (solid) tar as well.

Nothing solderable inside. I usually cut near bottom. Clean out guts.
Drill through holes to permit new radial caps leads to be poked through the
holes and then soldered to the terminals outside. Leave the terminals
attached (obviously)

I then reattach the top part with aluminum tape as previously mentioned.

On Mon, Jan 27, 2020, 9:32 PM Steve Hendrix <SteveHx@...>
wrote:

Wow! The collective knowledge and willingness to help here are amazing! It
will be a week or two before I can act on all this, other than to get some
parts ordered and on the way.

I'm thinking I like the idea of cutting off the tops of the caps and just
soldering a "modern" electrolytic in place of the old cap. Never having cut
open an electrolytic before, I'm not sure what to expect. How much messy
gunk am I going to get into? Will the metal on the inside be reasonably
receptive to solder, on the terminals I need to contact? Anything else I
should know, before trying my hand with a Dremel?

Steve Hendix



Sent via mobile annoyance thing. Please pardon any typos.