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Re: Disintegrating Handle on my TM503

 

And with the same active ingredient (phosphoric acid) as in most colas. I've used Diet Coke as a rust remover many times. Very effective (and frightening -- but at least my digestive tract is now rust-free).

--Tom

--
Prof. Thomas H. Lee
Allen Ctr., Rm. 205
420 Via Palou Mall
Stanford University
Stanford, CA 94305-4070

On 2/13/2025 12:21 PM, Jim Ford via groups.io wrote:
Say, is that Ospho the same as Naval Jelly? ISTR that NJ was some kind of acid.

Jim Ford
Laguna Hills, California, USA
Re: Disintegrating Handle on my TM503

 

Say, is that Ospho the same as Naval Jelly? ISTR that NJ was some kind of acid.

Jim Ford
Laguna Hills, California, USA

On Feb 13, 2025, at 11:57?AM, Dave Daniel via groups.io <kc0wjn@...> wrote:

?Also, for the rusty metal strap, there is a product named "Ospho" (a
phosphoric acid solution) that changes iron oxide into iron phosphate and
stops the iron oxidation process. One removes the loose rust and applies
Ospho and then, once the reaction is complete, cleans off the item.

DaveD
KC0WJN


On Thu, Feb 13, 2025 at 14:33 Roy J. Tellason, Sr. via groups.io <roy=
[email protected]> wrote:

On Thursday 13 February 2025 12:44:51 pm Greg Muir via groups.io wrote:
Most of my handle replacements have been with the older HP equipment
such as that found the 200CD oscillator which is a leather type. I have
had good success taking a badly deteriorated handle to the local saddle
shop who specializes in leather work. They fabricate handles that are
exact duplicates of the HP ones and even stain them the right colors.
If you can find a person or company that does this kind of work a custom
leather handle would look nice on the TM.

Hmm, there being a lot of amish around here that's a distinct
possibility...

I have a 5xx (can't recall the exact number) sitting out in the garage
with the same issue. Someone did send me another of that metal strip that
runs up the middle of the top of the scope, but it wasn't the right size
to fit on there, so I passed it along to somebody who could use it.

Gonna have to look around for somebody who works leather.

--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies.
--James
M Dakin
Re: Disintegrating Handle on my TM503

 

Also, for the rusty metal strap, there is a product named "Ospho" (a
phosphoric acid solution) that changes iron oxide into iron phosphate and
stops the iron oxidation process. One removes the loose rust and applies
Ospho and then, once the reaction is complete, cleans off the item.

DaveD
KC0WJN


On Thu, Feb 13, 2025 at 14:33 Roy J. Tellason, Sr. via groups.io <roy=
[email protected]> wrote:

On Thursday 13 February 2025 12:44:51 pm Greg Muir via groups.io wrote:
Most of my handle replacements have been with the older HP equipment
such as that found the 200CD oscillator which is a leather type. I have
had good success taking a badly deteriorated handle to the local saddle
shop who specializes in leather work. They fabricate handles that are
exact duplicates of the HP ones and even stain them the right colors.
If you can find a person or company that does this kind of work a custom
leather handle would look nice on the TM.

Hmm, there being a lot of amish around here that's a distinct
possibility...

I have a 5xx (can't recall the exact number) sitting out in the garage
with the same issue. Someone did send me another of that metal strip that
runs up the middle of the top of the scope, but it wasn't the right size
to fit on there, so I passed it along to somebody who could use it.

Gonna have to look around for somebody who works leather.

--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, a critter that can
be killed but can't be tamed. --Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies.
--James
M Dakin
Re: Disintegrating Handle on my TM503

 

Thanks for the very creative suggestion!

Cheers
Tom
Sent from an iThing; please forgive the typos and brevity

On Feb 13, 2025, at 10:16, greenboxmaven via groups.io <ka2ivy@...> wrote:

¡­ go to a junk store and find a large leather handbag that you can cut into a piece to wrap the metal strap. Roll it smoothly around the strap, tie it with dental floss, and shrink on two layers of shrink tubing. It works well.
Re: Disintegrating Handle on my TM503

 

On Thursday 13 February 2025 12:44:51 pm Greg Muir via groups.io wrote:
Most of my handle replacements have been with the older HP equipment such as that found the 200CD oscillator which is a leather type. I have had good success taking a badly deteriorated handle to the local saddle shop who specializes in leather work. They fabricate handles that are exact duplicates of the HP ones and even stain them the right colors.
If you can find a person or company that does this kind of work a custom leather handle would look nice on the TM.
Hmm, there being a lot of amish around here that's a distinct possibility...

I have a 5xx (can't recall the exact number) sitting out in the garage with the same issue. Someone did send me another of that metal strip that runs up the middle of the top of the scope, but it wasn't the right size to fit on there, so I passed it along to somebody who could use it.

Gonna have to look around for somebody who works leather.

--
Member of the toughest, meanest, deadliest, most unrelenting -- and
ablest -- form of life in this section of space, ?a critter that can
be killed but can't be tamed. ?--Robert A. Heinlein, "The Puppet Masters"
-
Information is more dangerous than cannon to a society ruled by lies. --James
M Dakin
Re: Disintegrating Handle on my TM503

 

Is the original leather covering on the metal strap still all there? If so, consider using some blue shrink tubing. Put on one layer, shrink it, slip a second layer over it and shrink it too. If the leather is gone, go to a junk store and find a large leather handbag that you can cut into a piece to wrap the metal strap. Roll it smoothly around the strap, tie it with dental floss, and shrink on two layers of shrink tubing. It works? well.

?? Brenda Gentry, KA2IVY

On 2/13/25 10:01, Jim Ford via groups.io wrote:
Hmmmm¡­ Seems like cold-shrink tape may come to the rescue. Made by Daburn Industries and Available from Digi-Key and maybe Mouser. Put some foam or bubble wrap around the metal handle and then wrap the tape around that. You stretch out the tape until it gets about half its starting width before you wrap, and voila, it fuses to itself. I have fixed everything from coaxial cables to garden hoses to rug shampoo machines with it. Hardest part is getting the tape off the backing. HTH. Jim Ford, Laguna Hills, California, USA
On Feb 12, 2025, at 2:47?PM, John Williams via groups.io <books4you4@...> wrote:

?Hi Benjamin. I personally have not had any success restoring old tektronix handles. However there are a lot of companies who make equipment handles. Ones intended for audio equipment usually will work if you are not going for an authentic restoration. Just google. Audio equipment handles. Here is one I found easily.
Re: Disintegrating Handle on my TM503

 

Most of my handle replacements have been with the older HP equipment such as that found the 200CD oscillator which is a leather type. I have had good success taking a badly deteriorated handle to the local saddle shop who specializes in leather work. They fabricate handles that are exact duplicates of the HP ones and even stain them the right colors.
If you can find a person or company that does this kind of work a custom leather handle would look nice on the TM.

Greg
Re: Alternative calibration pulsers for the Tek 11801 family.

 

Jon,

My post is NOT about testing the rise time of a scope. Its about TDR using Tek sampling scopes.

It is intended for owners of the later versions in the Tek sampling scope family which don't have the 15 ps calibrator. In later models Tek cut corners and only put in a 200 ps pulser. That's a substantial loss of resolution at 5 ps/div. It is an independent review of Leo's new product by a very well equipped and knowledgeable buyer who has the good fortune of having better kit than Leo.

Anyone who has a later member of the family with the 200 ps calibrator now has an alternative for doing TDR using an SD-26. I used my calibrator and a tee on an SD-26 for years before I found a working SD-24. You can see the ringing from the tee, but that's easy to understand. Strictly speaking it should have a 26 GHz splitter/combiner on it instead of a tee to preserve constant impedance. Best one I've got is only 12 GHz.

Scope shots using an 11801 and SD-32 of the new LBE-1322 pulser may be seen here compared directly to the 15 ps pulser in the 11801:



Have Fun!
Reg
Re: 152-0536-00 hot carrier diode

 

So I got some 1N5711 small signal Schottky (hot carrier) diodes.

Getting to CR515 in the TG501 is tricky, first you need to remove the metal shield on the top of the PCB, which is held in place by small screws. But you find the diode has been mounted flush with the stripline, and the back of the PCB has another metal shield that is not easily removable without damage.
I resorted to cracking the diode with a pair of sidecutters, and soldered the new diode in carefully to the existing pads.
Put the shield back and powered up and... nothing on the 1nS output.

At this point I started twiddling the trimmer caps of the 1nS filter, in the order the manual describes. First one had no noticeable effect. But the second one showed a bit of a signal at 1GHz. The trimmers are incredibly fussy, in particular the 2nd and third ones, a very small movement can cause the signal to drop 50%. After looping through about a dozen times I managed to get ~60mV output of a clean 1GHz sine wave. So maybe the diode wasn't bad, maybe a previous owner had got at it, who knows. The voltage I'm getting seems to agree with Raymond's, which is good enough, even if it's less than the 200mV the manual says is the target.

The 2nS output benefited from a little adjustment too and is giving out a healthy 1.2v signal now.

- Keith
Re: Disintegrating Handle on my TM503

 

Hmmmm¡­ Seems like cold-shrink tape may come to the rescue. Made by Daburn Industries and Available from Digi-Key and maybe Mouser. Put some foam or bubble wrap around the metal handle and then wrap the tape around that. You stretch out the tape until it gets about half its starting width before you wrap, and voila, it fuses to itself. I have fixed everything from coaxial cables to garden hoses to rug shampoo machines with it. Hardest part is getting the tape off the backing. HTH. Jim Ford, Laguna Hills, California, USA

On Feb 12, 2025, at 2:47?PM, John Williams via groups.io <books4you4@...> wrote:

?Hi Benjamin. I personally have not had any success restoring old tektronix handles. However there are a lot of companies who make equipment handles. Ones intended for audio equipment usually will work if you are not going for an authentic restoration. Just google. Audio equipment handles. Here is one I found easily.
Re: Disintegrating Handle on my TM503

 

Look for heater hose at an automotive parts place. This one is not Tek blue but close:
Re: Disintegrating Handle on my TM503

 

Just buy some garden hose, remove all the yellow color from it and, shazaam!

DaveD
KC0WJN


On Wed, Feb 12, 2025 at 18:49 Harvey White via groups.io <madyn=
[email protected]> wrote:

What, garden hoses don't come in Tek blue?

Harvey


On 2/12/2025 6:26 PM, John Griessen via groups.io wrote:
On 2/12/25 15:49, Harvey White wrote:
You might consider a length of garden hose or the equivalent for an
inexpensive replacement.

Or a Tek HP chimera: Blue case, greenish beige strap cover...
Re: Disintegrating Handle on my TM503

 

What, garden hoses don't come in Tek blue?

Harvey

On 2/12/2025 6:26 PM, John Griessen via groups.io wrote:
On 2/12/25 15:49, Harvey White wrote:
You might consider a length of garden hose or the equivalent for an inexpensive replacement.

Or a Tek HP chimera:? Blue case, greenish beige strap cover...
Re: Disintegrating Handle on my TM503

 

On 2/12/25 15:49, Harvey White wrote:
You might consider a length of garden hose or the equivalent for an inexpensive replacement.

Or a Tek HP chimera: Blue case, greenish beige strap cover...
Re: Disintegrating Handle on my TM503

 

You might consider a length of garden hose or the equivalent for an inexpensive replacement.

Harvey

On 2/12/2025 3:51 PM, Benjamin Badrakh via groups.io wrote:
Hello people of TekScopes,

I have a TM503 with a disintegrating handle. The blue outer sheath for the steel inner core has become brittle and ripped open. This just leaves the thin strip of rusty steel in its place, which is not exactly comfortable to hold and may give me tetanus.

I often carry this unit around back and forth between school and home, so the handle is functionally important for me. I've tried various solutions such as cardboard and tape, but they always fail prematurely.

Has anyone here experienced and found a solution to this problem?

Thanks,
Benjamin
Re: Disintegrating Handle on my TM503

 

Hi Benjamin. I personally have not had any success restoring old tektronix handles. However there are a lot of companies who make equipment handles. Ones intended for audio equipment usually will work if you are not going for an authentic restoration. Just google. Audio equipment handles. Here is one I found easily.

Re: Disintegrating Handle on my TM503

 

On 2/12/25 13:51, Benjamin Badrakh via groups.io wrote:
Has anyone here experienced and found a solution to this problem?
Not with a tm503 yet, but most 5xx scopes.

A method I like is wrap with leather and sew shut.

I might have some spare tek blue handle material from other cases. Would need to be cut down probably...

three layers of heat shrink would give a decent handle grip...
Disintegrating Handle on my TM503

 

Hello people of TekScopes,

I have a TM503 with a disintegrating handle. The blue outer sheath for the steel inner core has become brittle and ripped open. This just leaves the thin strip of rusty steel in its place, which is not exactly comfortable to hold and may give me tetanus.

I often carry this unit around back and forth between school and home, so the handle is functionally important for me. I've tried various solutions such as cardboard and tape, but they always fail prematurely.

Has anyone here experienced and found a solution to this problem?

Thanks,
Benjamin
Re: SC504 Trace Shadow

 

Edward,

First off thanks for your comment.

This scope has other issues right now. I need to understand more about crt acceleration. But will go through a full calibration if I can get everything else fixed.

Thanks!

Barry
Re: SC504 Trace Shadow

 

Ozan,

I took both of the hybrids out for inspection. I found an open trace on Pin1 and Pin2 of the hybrid that was installed on channel 2. I tried to repair the trace but ended up damaging several other traces. I don't think I can fix those.

History here is that I had swapped Ch1 Hybrid and Ch2 Hybrid expecting the symptoms to switch, they didn't. I did this several days before I asked for help. I wonder if the scope would have worked with the open traces in the hybrid 1 slot as original. The part numbers on both hybrids are the same, but the open circuits look intentional.

I also found a defect on one of the rubber band contacts, Contact #8. These switches are a bad design.

I have another SC504 on order.

Thanks for your help. This project is on hold for now!

Barry
861 - 880 of 208470