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Motorola 2N5928 Power Transistor Data Sheets wanted

 

Dear members :

It is OT , sorry , I am try to made a fixture for test TEK 175 for full power , so find a power transistor 2N5928 , I can find such Motorola 2N5928 , but compare with PowerTech 2N5928 ,which is TO-114 , Motorola 2N5928 is TO-63 !!!

I cannot find any data for Motorola 2N5928 anywhere ? Can anyone help me ? date code for Motorola 2N5928 is 0217.

Thanks for any information

Regard
Tony Cheung
NOV 2 2019

Re: A few pics from a new-to-me exhibit in the National Museum of Nuclear Science and History

battyhugh
 

If you are in Minneapolis - on the S side of the bridge across the river on the W side (if I remember correctly) - there is another relic - you have to decend about 6 stories down - there are masses of HB spec analysers and a rather large Van de Graffe generator - - very strange (I saw it in early 90's) - A Dr Weiblen was working at that time on using high voltage pulses to bust up moon rock. It would be rather interesting to document the remaining residues of the 50's and 60's (on the marshes near Palo Alto is an old radio transmission facility - might be interesting... but wait.. there's more!

Antique (aka legacy) Mac programs ..help please

battyhugh
 

i am trying to get a working copy of MacLab (3.5 or there-abouts). i have the hardware - we urgently need to run an old program.
any ideas as to where we might look? (Mac OS 9.2)

Thanks

hugh

Re: Correct Silver solder

battyhugh
 

I seem to remember a long time ago - that Tektronix actually put a short length of the correct solder wrapped around a post.
You might look for it.

h

Re: Correct Silver solder

Craig Sawyers <c.sawyers@...>
 

Under no circumstances use lead free solder on ceramic strips! That is a guarantee of disaster.
First the melting point is too high, and second it makes a strange grainy intermetallic with the
lead based solder that Tektronix used.

And - with reference to Richard Pope's mail - never ever use solder that is simply 60:40 or 63:37
(ie without added silver) - that will leach the silver out of the ceramic strip notches. It is most
definitely NOT what Tektronix used in this application.

Others have already said that the easily available lead based solders with added silver contain 2%
silver, and are just fine for ceramic notches.

If you want more silver, the only leaded solder that contains 4% silver is made by WBT - but it is
about 4x the price.

Craig

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of greenboxmaven via
Groups.Io
Sent: 02 November 2019 02:08
To: TekScopes@groups.io
Subject: [TekScopes] Correct Silver solder

I am beginning restoration on a 555 I got a few months ago. What is the
correct alloy of solder for the ceramic tie strips? I have found both
tin/lead/silver and lead-free, both with 2% silver content . Are these satisfactory? Is 2%
silver
enough, or is a richer alloy needed? Thanks, Bruce, KA2IVY

Re: 468 With Odd Trace Timing issue when in Vertical ALT Mode Only.

Mlynch001
 

On Sat, Nov 2, 2019 at 12:40 AM, Mlynch001 wrote:


And it must be something which does not light the TRIGGER LED when this
happens.
Should have said: "And it must be something which does not ALWAYS light the TRIGGER LED when this happens."

It seems to happen regardless of the trigger control position or whether the trigger LED is on or off.

I'm still going to take a look at the trigger circuitry.
--
Michael Lynch
Dardanelle, AR

Re: 468 With Odd Trace Timing issue when in Vertical ALT Mode Only.

Mlynch001
 

On Fri, Nov 1, 2019 at 11:48 PM, DaveH52 wrote:


I'm thinking that it looks like it's not syncing to the trigger signal you're
feeding it, and that it's showing Ch-A, CH-B, and the Trigger input
alternately. Just a guess, take it with a grain of salt-substitute.
Dave,

That is something to consider. Possibly an "inadvertent" trigger from somewhere? In these pictures I am not feeding any signals to the scope. Nothing whatsoever going in. So are you thinking that there might be a problem with the trigger circuitry? If it is triggering, it is doing so from a source within the instrument. So maybe from the "LINE" trigger pick off? And it must be something which does not light the TRIGGER LED when this happens. When I do feed a signal, I get the same sort of reaction on the resulting waveform(s). I will check the trigger circuitry, per the manual. Who knows, I might find something that I did not think of. I appreciate your reply and the advice.

Thanks!

--
Michael Lynch
Dardanelle, AR

2465 HV Power Supply Issue

DaveH52
 

I've finally got the LVPS straightened out and back in. I'll be taking it back out again later to replace a couple RIFA caps that haven't exploded - yet.
It powers up, after a few seconds some relays kerchunk, and the front panel lights up like it should and responds to me poking the buttons and switches.
The problem now is there's no trace on the screen where there used to be one. No sign of the CRT filament coming on. The filament checks OK for continuity, The transformer filament winding checks for continuity. Powering it up reveals no filament voltage. I'm hoping it's just something in the HV board primary circuit, since I don't want to muck around the seconday side too much. I don't want to go flying across the room!
Before I start poking around in there, are there any "usual suspects" I should consider first? Any simple checks I can do without the power on?

Thanks!
DaveH

Re: 468 With Odd Trace Timing issue when in Vertical ALT Mode Only.

DaveH52
 

I'm thinking that it looks like it's not syncing to the trigger signal you're feeding it, and that it's showing Ch-A, CH-B, and the Trigger input alternately. Just a guess, take it with a grain of salt-substitute.

Re: Correct Silver solder

Martin
 

2% silver is what you need for any equipment that has silver plated ceramic strips. I've read that Tek supplied 3% with the scopes, but everything else that I've read says that 2% will prevent silver from leeching off of the ceramic.

Re: Correct Silver solder

Jacques Fortin
 

At least 3% alloy is needed, according to the manuals.

Le 1 nov. 2019 à 22:08, greenboxmaven via Groups.Io <ka2ivy=verizon.net@groups.io> a écrit :

I am beginning restoration on a 555 I got a few months ago. What is the correct alloy of solder for the ceramic tie strips? I have found both tin/lead/silver and lead-free, both with 2% silver content . Are these satisfactory? Is 2% silver enough, or is a richer alloy needed? Thanks, Bruce, KA2IVY

Re: Correct Silver solder

tss_steve_990
 

Unless your scope has a small coil of solder inside, which was standard
issue back then, IMHO the closest readily available solder is SN62. It
is eutectic solder (63% Tin, 37% lead) with 2% silver added. It has
enough silver not to leach the silver from the ceramic strips and melts
at a low temperature.

I would never use Lead Free solder on anything I cared about.

Steve Hogan

714 904-6636

On 2019-11-01 19:53, Jamie Ostrowski wrote:

Also, it's at the 5:35 mark in that video where they specify the exact
composition needed...just fyi.

On Fri, Nov 1, 2019 at 9:50 PM Jamie Ostrowski <jamie.ostrowski@...>
wrote:

60% tin/ 37% lead, and 3% SILVER...sorry for the typo!

On Fri, Nov 1, 2019 at 9:49 PM Jamie Ostrowski <jamie.ostrowski@...>
wrote:

Tektronix in the 50's said the actual correct solder is 60% tin, 37%
lead, and 3% solder. The details are highlighted in this video, made in the
50s by Tektronix, for soldering to ceramic strips.

Here is the video which covers the procedure in detail:

https://www.youtube.com/watch?v=RpB5JqGo1co

Maybe 2% would work, but if you're working on restoring a 555, why take
the chance on compromise?

Just me! :-)

Good luck with your project.

On Fri, Nov 1, 2019 at 9:26 PM Richard R. Pope <mechanic_2@...>
wrote:

Bruce,
I would use the same solder that the original builders used. 60/40
or 63/37 lead/tin rosin core solder.
GOD Bless and Thanks,
rich!

On 11/1/2019 9:08 PM, greenboxmaven via Groups.Io wrote: I am beginning restoration on a 555 I got a few months ago. What is
the correct alloy of solder for the ceramic tie strips? I have found
both tin/lead/silver and lead-free, both with 2% silver content . Are
these satisfactory? Is 2% silver enough, or is a richer alloy needed?
Thanks, Bruce, KA2IVY

Re: Correct Silver solder

Jamie Ostrowski
 

Also, it's at the 5:35 mark in that video where they specify the exact
composition needed...just fyi.

On Fri, Nov 1, 2019 at 9:50 PM Jamie Ostrowski <jamie.ostrowski@...>
wrote:


60% tin/ 37% lead, and 3% SILVER...sorry for the typo!

On Fri, Nov 1, 2019 at 9:49 PM Jamie Ostrowski <jamie.ostrowski@...>
wrote:


Tektronix in the 50's said the actual correct solder is 60% tin, 37%
lead, and 3% solder. The details are highlighted in this video, made in the
50s by Tektronix, for soldering to ceramic strips.

Here is the video which covers the procedure in detail:

https://www.youtube.com/watch?v=RpB5JqGo1co

Maybe 2% would work, but if you're working on restoring a 555, why take
the chance on compromise?

Just me! :-)

Good luck with your project.



On Fri, Nov 1, 2019 at 9:26 PM Richard R. Pope <mechanic_2@...>
wrote:

Bruce,
I would use the same solder that the original builders used. 60/40
or 63/37 lead/tin rosin core solder.
GOD Bless and Thanks,
rich!

On 11/1/2019 9:08 PM, greenboxmaven via Groups.Io wrote:
I am beginning restoration on a 555 I got a few months ago. What is
the correct alloy of solder for the ceramic tie strips? I have found
both tin/lead/silver and lead-free, both with 2% silver content . Are
these satisfactory? Is 2% silver enough, or is a richer alloy needed?
Thanks, Bruce, KA2IVY







Re: Correct Silver solder

Jamie Ostrowski
 

60% tin/ 37% lead, and 3% SILVER...sorry for the typo!

On Fri, Nov 1, 2019 at 9:49 PM Jamie Ostrowski <jamie.ostrowski@...>
wrote:


Tektronix in the 50's said the actual correct solder is 60% tin, 37% lead,
and 3% solder. The details are highlighted in this video, made in the 50s
by Tektronix, for soldering to ceramic strips.

Here is the video which covers the procedure in detail:

https://www.youtube.com/watch?v=RpB5JqGo1co

Maybe 2% would work, but if you're working on restoring a 555, why take
the chance on compromise?

Just me! :-)

Good luck with your project.



On Fri, Nov 1, 2019 at 9:26 PM Richard R. Pope <mechanic_2@...>
wrote:

Bruce,
I would use the same solder that the original builders used. 60/40
or 63/37 lead/tin rosin core solder.
GOD Bless and Thanks,
rich!

On 11/1/2019 9:08 PM, greenboxmaven via Groups.Io wrote:
I am beginning restoration on a 555 I got a few months ago. What is
the correct alloy of solder for the ceramic tie strips? I have found
both tin/lead/silver and lead-free, both with 2% silver content . Are
these satisfactory? Is 2% silver enough, or is a richer alloy needed?
Thanks, Bruce, KA2IVY







Re: Correct Silver solder

Jamie Ostrowski
 

Tektronix in the 50's said the actual correct solder is 60% tin, 37% lead,
and 3% solder. The details are highlighted in this video, made in the 50s
by Tektronix, for soldering to ceramic strips.

Here is the video which covers the procedure in detail:

https://www.youtube.com/watch?v=RpB5JqGo1co

Maybe 2% would work, but if you're working on restoring a 555, why take the
chance on compromise?

Just me! :-)

Good luck with your project.



On Fri, Nov 1, 2019 at 9:26 PM Richard R. Pope <mechanic_2@...>
wrote:

Bruce,
I would use the same solder that the original builders used. 60/40
or 63/37 lead/tin rosin core solder.
GOD Bless and Thanks,
rich!

On 11/1/2019 9:08 PM, greenboxmaven via Groups.Io wrote:
I am beginning restoration on a 555 I got a few months ago. What is
the correct alloy of solder for the ceramic tie strips? I have found
both tin/lead/silver and lead-free, both with 2% silver content . Are
these satisfactory? Is 2% silver enough, or is a richer alloy needed?
Thanks, Bruce, KA2IVY







Re: Correct Silver solder

Richard R. Pope
 

Bruce,
I would use the same solder that the original builders used. 60/40 or 63/37 lead/tin rosin core solder.
GOD Bless and Thanks,
rich!

On 11/1/2019 9:08 PM, greenboxmaven via Groups.Io wrote:
I am beginning restoration on a 555 I got a few months ago. What is the correct alloy of solder for the ceramic tie strips? I have found both tin/lead/silver and lead-free, both with 2% silver content . Are these satisfactory? Is 2% silver enough, or is a richer alloy needed? Thanks, Bruce, KA2IVY



Re: Correct Silver solder

Bob Albert
 

I think 2% is okay, with lead preferred since that's what they used.
In my case, I found a piece of silver solder my dad had for his jewelry repairs and using some of it alternately with tin-lead seems to do the job for the terminal strips.  So apparently the fraction isn't critical.
Bob

On Friday, November 1, 2019, 07:11:24 PM PDT, greenboxmaven via Groups.Io <ka2ivy=verizon.net@groups.io> wrote:

I am beginning restoration on a 555 I got a few months ago. What is the
correct alloy of solder for the ceramic tie strips?  I have found both
tin/lead/silver and lead-free, both with 2% silver content .  Are these
satisfactory?  Is 2% silver enough, or is a richer alloy needed? Thanks,
Bruce, KA2IVY

Correct Silver solder

greenboxmaven
 

I am beginning restoration on a 555 I got a few months ago. What is the correct alloy of solder for the ceramic tie strips? I have found both tin/lead/silver and lead-free, both with 2% silver content . Are these satisfactory? Is 2% silver enough, or is a richer alloy needed? Thanks, Bruce, KA2IVY

Re: A few pics from a new-to-me exhibit in the National Museum of Nuclear Science and History

J Mcvein
 

Put on your Atomic Age bucket list a visit to the Hanford 'B'reactor.  Some vintage Tek in a 1968 time capsule.  Also themost extensive thermocouple crosspoint switching system around.
JimMc

On Friday, November 1, 2019, 4:28:12 PM PDT, sdturne@q.com <sdturne@q.com> wrote:

https://groups.io/g/TekScopes/album?id=128766

The exhibit depicts the critical assembly labs that operated at Los Alamos Scientific Laboratory (now Los Alamos National Laboratory). The scientists who worked in them (rather bravely I might add) were working to quantify critical masses of plutonium. A number of fatal criticality accidents occurred in the years these experiments were carried out. Robotic assembly was developed later, with the scientists safely shielded.

Anyway, there's a selection of vintage test equipment that members of the list may enjoy, mainly a 535 and a DuMont oscillograph. Most of the stuff in the exhibit is authentic, ex LANL gear. Other than the criticality experiments.

Sean

A few pics from a new-to-me exhibit in the National Museum of Nuclear Science and History

@0culus
 

https://groups.io/g/TekScopes/album?id=128766

The exhibit depicts the critical assembly labs that operated at Los Alamos Scientific Laboratory (now Los Alamos National Laboratory). The scientists who worked in them (rather bravely I might add) were working to quantify critical masses of plutonium. A number of fatal criticality accidents occurred in the years these experiments were carried out. Robotic assembly was developed later, with the scientists safely shielded.

Anyway, there's a selection of vintage test equipment that members of the list may enjoy, mainly a 535 and a DuMont oscillograph. Most of the stuff in the exhibit is authentic, ex LANL gear. Other than the criticality experiments.

Sean