Date   

Re: Leaking capacitors once again.

s92187
 

David, I agree on your suggestion to use an electrolytic as a replacement. Capacitors being made today are substantially better than what was available when this equipment was designed in the 1980s, at that time I'm guessing that the engineers that spec'd a tantalum wanted a good low ESR part and they didn't have as many other options to choose from at the time. And, although a tantalum is a lot more expensive, maybe that wasn't much of a concern for four parts going into a product that sold for $32,450.00 in 1991.

Vishay makes a high temperature rated electrolytic, the 118 AHT series which is spec'd for 8000 hrs @ 125 C, the 100 uF part is the same size as the 50 uF tantalum it is replacing, plus the electrolytic has lower ESR and lower impedance, and is less than 1/10 the cost, so I'm going to use that as a replacement. I think that these replacement caps will last as long as anything else in the SA.

Terry


Re: Transistor Cross Reference - Now N101 transistor info

Chuck Harris
 

Take the top off of one, and look at the die under a microscope.
They are often well marked.

-Chuck Harris

Dave Wise wrote:

Thanks for your hard work, Jon. At least you had some lubrication. :)

If you can post a link to their logo, please do. I didn't see much at their web site, and a general image search produced too much noise.

I'm willing to stipulate that my parts are counterfeits; everything gets faked these days. But usually the fakes function poorly if at all, and these are really really good. I wish I knew what their real part number is!

Regards,
Dave Wise


Re: Transistor Cross Reference - Now N101 transistor info

Dave Wise
 

Thanks for your hard work, Jon. At least you had some lubrication. :)

If you can post a link to their logo, please do. I didn't see much at their web site, and a general image search produced too much noise.

I'm willing to stipulate that my parts are counterfeits; everything gets faked these days. But usually the fakes function poorly if at all, and these are really really good. I wish I knew what their real part number is!

Regards,
Dave Wise
________________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of Jon Batters <jonbatters32@...>
Sent: Wednesday, January 17, 2018 1:10 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Transistor Cross Reference - Now N101 transistor info

Hi Dave, So it took 7 hours and all my Guinness to finally figure this out. Here is my Report and Opinion:

1) PESE ELECRONICS CO. LTD. and WWW.PESE.CO .

2) The Logo is a crude variation of their Chinese PESE Logo.

3) If from W. Germany, it would be a Pro-Electron #, not a JEDEC # ! It would be sold as a cross for the JEDEC 2N1304.

4) "W.Germany" print is a FRAUD to imply German quality, to aid sales. I spent 1.5 hours "in" Germany via Google researching private & government databases
before Smelling a Rat , that in reality, this part does not and has not existed there. Let alone, this strange company.

5) Package print quality is poor. That IS a bad sign.

6) PESE buys and resells stock. They probably contract to weird little shops to make "2N1304" stock, so there is no info, no data sheets, etc. I saw a video on
these little Family run shops that was just shocking and scary.

7) I don't know why to buy weird stock, from any one. I would not like to go back in 2 days/years later to replace w/ normal parts. Think Digikey, Newark or any of the Normal
distributors , instead of Kow Puck U Corp out of Asia. BTW I've found Pro-Electron ( European ) stock to be better than JEDEC because their Voltage specs are usually higher for
the "same " part. If you cannot find the OEM or get a Data Sheet, you should consider that a ....Bad Sign... and run away.......

8) Now I have to make a Beer Run...............

Jon Batters, Oregon


Re: Help restoring a 547 scope

Chuck Harris
 

There is about 100W worth of filament current alone.
The fan will do nothing... and is probably dry of
lubrication anyway.

You need to dry your scope fully. The easiest way
to do that is to put a 60W light bulb in the vertical
plugin area, followed by a computer sized muffin fan.
Install the scope's side covers, and drape a towel
over the scope.

Let your scope dry this way for a few days.

After it is good and dry, plug your scope in, and see
what happens.

-Chuck Harris

felix_cantor via Groups.Io wrote:

On Thu, Jan 18, 2018 at 07:58 am, Chuck Harris wrote:


The 547 draws a lot more than 100W in normal operation.
It will *not* start up with a 100W bulb in series.

If you really want to use a bulb as a safety fuse, you
are going to have to use more like 500W worth of bulbs.

-Chuck Harris


Re: Help restoring a 547 scope

felix_cantor@...
 

ok now some observations:

-It works much better than before the wash, the trace much more stable though it still deflects a little.... has some sort of vertical quick random deflection. But i guess it can be that some transistors need to have their legs cleaned. Seems like there is a bad contact somewhere.

-Time Base B still doesnt trigger.

-At first the trace appears super bright and it cant be adjusted with the intensity control, after a few seconds it dims a bit and the intensity control starts working.

-also the first inch of the trace is a little dimmer than the rest with the intensity control adjusted for nice visible trace, if I adjust it brighter then all the trace appear with the same intensity.


Those are the problems I acknowledge so far.

Sorry for my english.
All the best.


Re: Help restoring a 547 scope

felix_cantor@...
 

ok.... ignorance is the mother of all mistakes. It worked!

god! i love this scope.... the trace is so sharp! Amazing.

now i need to fix all the other issues.


Re: Help restoring a 547 scope

felix_cantor@...
 

On Thu, Jan 18, 2018 at 07:58 am, Chuck Harris wrote:


The 547 draws a lot more than 100W in normal operation.
It will *not* start up with a 100W bulb in series.

If you really want to use a bulb as a safety fuse, you
are going to have to use more like 500W worth of bulbs.

-Chuck Harris
Hey there Chuck!

Thanks for you input.

Even the fan will do nothing? ok will try without the current limiter right now.... scary.


Re: Help restoring a 547 scope

Chuck Harris
 

The 547 draws a lot more than 100W in normal operation.
It will *not* start up with a 100W bulb in series.

If you really want to use a bulb as a safety fuse, you
are going to have to use more like 500W worth of bulbs.

-Chuck Harris

felix_cantor via Groups.Io wrote:

Hey there!

On Wed, Jan 17, 2018 at 06:56 pm, Pete Lancashire wrote:


When you finished washing it, do you use compressed dry air (oil free) and
have a fan or something to keep the air moving all the time ?
nope... i just leaved it at the sunlight in the garden (it is windy here). After I started this thread i placed the scope for another three days at the sun, now i need to try turning it on again

What is the wattage of the lamp ?
100watts

Is your line voltage 120V or 240V ?
220V

Did you try turning it on with all the tubes pulled ?
nope

Is the Amperite switch open when cold ?
thats the k600 bulb? if so then yes.

-pete
Thank you!


Re: Help restoring a 547 scope

Chuck Harris
 

Relatively pure water is a relatively high impedance uhmmm? Load.

Simply washing a scope is unlikely to cause the scope to draw
excess amounts of current, unless you filled the transformer full
of water. You said that you didn't.

I would put my faith in the scope's fuse, and simply plug it in
and turn it on. If the fuse blows, figure out why.

-Chuck Harris

felix_cantor via Groups.Io wrote:

On Wed, Jan 17, 2018 at 06:51 pm, David Hess wrote:


The 547 has like a 30 second power on delay so you have to wait that
long.

What do you mean "the light as at full bright"?

The place to start is checking the power supply voltages. Some of
them are hundreds of volts so care is needed.
Thanks for the response,

I mean that the bulb from the current limiter was fully bright when i turned on the scope, it didn´t dim at all... and the green lamp from the scope stayed off.


Re: Help restoring a 547 scope

felix_cantor@...
 

... I really appreciate your help fellas! Have a great day.


Re: Help restoring a 547 scope

felix_cantor@...
 

On Thu, Jan 18, 2018 at 03:02 am, Morris Odell wrote:


I wouldn't bother with a lamp current limiter in series, especially as it
seems to have been working already before it was washed. Just make sure the
right size fuse is in there and let 'er rip. The fan should start straight
away and after what will seem like a long wait for the time delay relay you
should hear a click and the scope should come alive. Let us know what happens
next :-)

Morris
I´m kinda scared of trying that... because with the current limiter the fan did nothing, the scope remained dead... dunno, maybe i should take the risk


Re: Help restoring a 547 scope

felix_cantor@...
 
Edited

Hey there!

On Wed, Jan 17, 2018 at 06:56 pm, Pete Lancashire wrote:


When you finished washing it, do you use compressed dry air (oil free) and
have a fan or something to keep the air moving all the time ?
nope... i just leaved it at the sunlight in the garden (it is windy here). After I started this thread i placed the scope for another three days at the sun, now i need to try turning it on again

What is the wattage of the lamp ?
100watts

Is your line voltage 120V or 240V ?
220V

Did you try turning it on with all the tubes pulled ?
nope

Is the Amperite switch open when cold ?
thats the k600 bulb? if so then yes.

-pete
Thank you!


Re: Help restoring a 547 scope

felix_cantor@...
 

On Wed, Jan 17, 2018 at 06:51 pm, David Hess wrote:


The 547 has like a 30 second power on delay so you have to wait that
long.

What do you mean "the light as at full bright"?

The place to start is checking the power supply voltages. Some of
them are hundreds of volts so care is needed.
Thanks for the response,

I mean that the bulb from the current limiter was fully bright when i turned on the scope, it didn´t dim at all... and the green lamp from the scope stayed off.


1L5 2nd Oscillator & Mixer

Christopher Hilton-Johnson
 

Attempting to calibrate my vintage 1L5, I found the core for the 2nd Mixer broken up (presumably a major reason why calibration had previously failed).
The part number is 114-0178-00 and seems completely unobtanium. Its spec, according to the parts list is a single coil inductor variable between 1300 & 3000uh. It peaks at 100khz with 15nf across it.
The core in the adjacent 3.1mhz crystal oscillator peaking coil (part 114-0233-00) looks damaged as well, and the coil is similarly lost to myth and legend.
Does anyone have the specifications for these parts, particularly the 114-0178-00 part, and most importantly the winding specs, so I can try to grow my own?
anyone got a spare?
or a 2LO module from a dead 1L5 they might part with?
or a suggestion for an alternative?
thanks
Chris HJ


Re: Help restoring a 547 scope

Morris Odell
 

I wouldn't bother with a lamp current limiter in series, especially as it seems to have been working already before it was washed. Just make sure the right size fuse is in there and let 'er rip. The fan should start straight away and after what will seem like a long wait for the time delay relay you should hear a click and the scope should come alive. Let us know what happens next :-)

Morris


Re: Tek 475 HV multiplier replacement

Michael A. Terrell
 

You need to make sure the solder joint is a ball. No sharp points. I replaced a lot of flyback transformers in TVs in the '60s and '70s. I saw a lot of bad work from other shops where they would just squeeze a wad of silicone HV putty over a sloppy solder job. The HV putty only delayed the next failure. The instruction sheets stressed the proper solder techniques, which were ignored. These were the same ones with the attitude that any component that was static sensitive was poorly designed crap.

-----Original Message-----
From: David Hess <@DWH>
Sent: Jan 17, 2018 9:53 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Tek 475 HV multiplier replacement

Cut and solder splice the old high voltage multiplier lead to the new
one. Paint the soldered joint with corona dope and then wrap that
area with insulating tape.

On Wed, 10 Jan 2018 08:18:06 -0800, you wrote:

Hi,
the HV multiplier in my Tek 475 is defective. I will replace it with a multiplier HRT507.
This is done several times as I have read in several forums.
My question is how to connect the HV-lead from the new multiplier to the
original HV-cable, so that no sparks will come out.
Any tips will be wellcome.
Thank you
Dieter


Michael A. Terrell


Tek 2715 SA freq norm failing

Jeff Woolsey
 

Seeking sage advice, or the advice of sages, whichever works.

I had the thing running for about a week, doing a max holds overnight
and "plotting" the results.  Afterwards, I find I can no longer count
the center frequency, failing with

FREQ NORM SUGGESTED (1ST LO)

and when I try to do the reference frequency normalization
[UTIL][5][5][1][1] with an external 10MHz, that fails as well.  Trying
to use last norm or default values doesn't "fail", but I still can't
count center frequencies.  This used to work.

Running a full normalization finishes (eventually), but doesn't cure the
problem either. REF FREQ NORM still FAILed.

Does this thing have a battery-backed NVRAM that is starting to fail? 
The filesystem looks OK.

--
Jeff Woolsey {{woolsey,jlw}@jlw,first.last@{gmail,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: Graded display on CSA803 / 11800 series

John Miles
 

That does look nice. Where did the CSA803-graded.png image come from?

-- john, KE5FX

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of
Leo Bodnar
Sent: Sunday, January 14, 2018 3:15 AM
To: TekScopes@groups.io
Subject: [TekScopes] Graded display on CSA803 / 11800 series

If somebody is still actively maintaining user applications for CSA803 / 11800
series, please consider adding graded display data download.

Behind ugly screen with five eye-watering colours there actually is a 256x512
array of 16-bit deep persistence bins that can be downloaded with "DISP?
DATA" query and post-processed into something more pleasing.

You can achieve almost analogue-like quality of screenshots.

Here is an example of a high jitter signal looking on a screenshot and the
data it returns with the above query.

http://www.leobodnar.com/files/CSA803A-screenshot.png
http://www.leobodnar.com/files/CSA803-graded.png

Cheers
Leo


Re: Help restoring a 547 scope

Pete Lancashire
 

When you finished washing it, do you use compressed dry air (oil free) and
have a fan or something to keep the air moving all the time ?

What is the wattage of the lamp ?

Is your line voltage 120V or 240V ?

Did you try turning it on with all the tubes pulled ?

Is the Amperite switch open when cold ?

-pete

On Wed, Jan 17, 2018 at 6:51 PM, David Hess <@DWH> wrote:

The 547 has like a 30 second power on delay so you have to wait that
long.

What do you mean "the light as at full bright"?

The place to start is checking the power supply voltages. Some of
them are hundreds of volts so care is needed.

On Thu, 11 Jan 2018 09:31:37 -0800, you wrote:

Hello everyone! New guy in town here ;)

I just purchased an used 547 that I want to fully restore.

It was in working condition when I bought it but the traces and the
trigger systems didn`t work that well. Channel B didn`t even trigger.
The interior was quite dusty and dirty, so I decided to give it a bath as
per the manual recommendation. I covered the transformer and took great
care not to wet it and also not to wet the high voltage section for the
CRT. After the wash I placed it at the sun for around 2 days and kept it in
the house for another 4 days or so before trying to turn it on again. After
that I plugged the unit to a current limiter just in case something was
wrong with the scope after the wetting, and it seemingly was broken! The
light was at full bright when I turned on the scope though the scope
remained without any sign of being powered up. So I guess there is a short
right at the beginning of the power section....

I`m some sort of an amateur so I`m not so sure how to proceed right now
without screwing up the scope anymore. I`ve build a few tube amplifiers and
restored a few old test equipment, so I know the basics really.

Any help will be very much appreciated.

Thanks.
F.



Re: Tek 475 HV multiplier replacement

 

Cut and solder splice the old high voltage multiplier lead to the new
one. Paint the soldered joint with corona dope and then wrap that
area with insulating tape.

On Wed, 10 Jan 2018 08:18:06 -0800, you wrote:

Hi,
the HV multiplier in my Tek 475 is defective. I will replace it with a multiplier HRT507.
This is done several times as I have read in several forums.
My question is how to connect the HV-lead from the new multiplier to the
original HV-cable, so that no sparks will come out.
Any tips will be wellcome.
Thank you
Dieter