Date   
Re: TDS3044B repair

David Kuhn
 

Tom,

I'm curious how you made out with your TDS3044B? (TDS3034??)

Dave

On Sat, Oct 26, 2019 at 10:50 PM Tom B <tbryan@...> wrote:

Hello All,

I am working on a TDS3044B that just has a white screen. Nothing else
comes up on the display. The controls seem to respond, that is, the
lights go on and off and there are relay clicks when I hit the Auto Set
button. The service manual is not much help. The manual also does not
tell you what the test points do. I don't want to buy a new display
unless necessary. Anybody got advice on where to start?

Tom Bryan





Air filters for 500 series.

greenboxmaven
 

I have obtained some 500 series scopes in the last month or so. One of them, a 585 is absolutely filthy but shows signs of life. Needless to say, the aluminum mesh filter is gone and has been gone for years. How effective are those filters when properly cleaned and treated? I have seen people use the foam filter material from air conditioners, but wonder if they are effective. I am considering getting a small fine particle trapping furnace filter and cutting and refitting it's cardboard rim to fit the scope's filter frame. What experiences have others had with filters?

Bruce Gentry, KA2IVY

WTB: 82 plug in for 585

greenboxmaven
 

Yesterday I picked up a good but filthy 585A with the cart. Does anyone have an 82 dual channel plug-in for it? There is one on Epay that looks like it survived a missle attack, but the price is beyond all reason. Thanks, Bruce KA2IVY

Re: Have to evaluate a 494P

Chuck Harris
 

Roy,

The problem is when the 494P is out of its case for service.
My warning comes to you because you were talking about doing
some service on yours, and it didn't sound to me like you had
done much if any work inside of a 494 before.

The bottom is covered with little aluminum boxes that get
pressed upon if the 494 is allowed to overhang the bench
while you are working, or handling the SA.

They are the thinnest of aluminum, and the SMA connectors are
bolted to that thin aluminum case with their necked down center
pins passing through the PCB, and soldered. The center pins
neck down to 1/64 inch, and will snap off in a blink if the
aluminum case is flexed. From that point forward, there will
be intermittents that are really hard to find. They will appear
like cable/connector problems, as they will change when you
touch, tighten, remove the SMA cables and connectors.

You can also make this happen by getting too neanderthal with
the SMA connectors.

The last one I fixed was on the A24 Phase Gate. Both SMA
connectors sheared the very thin sections of the center pins
that passed through the circuit boards and were soldered on
the component side of the board. Because the boards are screwed
to the aluminum chassis, and so are the SMA connectors, every
thing you can see without removing the board looks great: Nice
fillet on center pins, tight SMA nuts on chassis, and very
intermittent operation.

It manifests itself as loss of ability to phase lock at, I think,
200KHz and below.

They can be fixed by either buying new connectors ($$$), or by
slipping eyelets over the center pins to extend them to the PCB
where the whole assembly can be soldered blind from the
component side of the board... sort of a telescoping surface mount,
where the eyelets telescope to touch the board, and then you feed
enough solder through the holes the original (broken) pins passed
through the board into the eyelets to solder the eyelets in place.

When the 494 is in its protective case it can be stacked
as high as you want, so long as the case doesn't get bent.

-Chuck Harris

Roy Thistle wrote:

Hi Chuck:
Thanks! That's really good to know.
This guy is the bottom turtle for sure, unless... is it safe to put stuff on top of it?
Right at the moment it's doing a very good job of holding the floor down... I'm still trying to pop my shoulder back in.
I've seen a few banged up 49xy; but this one is in very good shape.
Of all the Tek 400 stuff I've run across... I like the look, layout, and the just the overall styling of this instrument the best.
Best regards and wishes.
Roy

Re: DPO7054 question about Edge button

 

Thanks Tam,

I was successfully to replace two LEDs. All the ones I purchased didn’t match the factory ones so I ended up purchasing a cheap used Tektronix keypad and removing the LEDs.

Manuel

Re: Have to evaluate a 494P

Roy Thistle
 

Hi Chuck:
Thanks! That's really good to know.
This guy is the bottom turtle for sure, unless... is it safe to put stuff on top of it?
Right at the moment it's doing a very good job of holding the floor down... I'm still trying to pop my shoulder back in.
I've seen a few banged up 49xy; but this one is in very good shape.
Of all the Tek 400 stuff I've run across... I like the look, layout, and the just the overall styling of this instrument the best.
Best regards and wishes.
Roy

Re: Great video for 500 series Tek restorers

Dave Seiter
 

It doesn't even come with the power supply or cable!  I can't wait to see what it sells for.
-Dave

On Thursday, November 14, 2019, 05:17:54 PM PST, John Williams <books4you@...> wrote:

Btw the 555 on eBay that was priced at $4750 has been marked down to $1900. Bet there is a crowd of buyers there right now. You gotta laugh so you don’t cry.

Re: Great video for 500 series Tek restorers

Jamie Ostrowski
 

Yeah it will be interesting to see what it winds up going for. It can be
fun watching the pricing play out. In the last few months I have seen them
going from $250 for some to around $800 for others!

On Thu, Nov 14, 2019 at 7:17 PM John Williams <books4you@...> wrote:

Btw the 555 on eBay that was priced at $4750 has been marked down to
$1900. Bet there is a crowd of buyers there right now. You gotta laugh so
you don’t cry.



Re: Great video for 500 series Tek restorers

John Williams
 

Btw the 555 on eBay that was priced at $4750 has been marked down to $1900. Bet there is a crowd of buyers there right now. You gotta laugh so you don’t cry.

Re: Have to evaluate a 494P

Chuck Harris
 

One thing I would like to warn you about is letting the
very heavy 494P sit halfway on the bench, and halfway
off. The pressure gets put on an IF module midships,
and breaks the two SMA connectors that connect to the circuit
board. The next thing you know, your 494 doesn't lock anymore
in the sub 200KHz settings.

-Chuck Harris

Roy Thistle wrote:

Hi All:
I have to start evaluating a 494P (starting with powering it up).
I've got the docs; but, it's no fun doing it alone (and.. I want to have fun!)
There's posts on the 49xy here... and I've been reading them.
So far, I was able to move it!... without seeing the chiropractor! (A process not recommended... as apparently a 494P is designed to stay in place, in one place.)
I'm more familiar with older analog HP SAs, and some of the newer digital ones... so any discussion would be helpful.
Best regards and wishes to all.
Roy



Re: Items for Sale

Roy Thistle
 

Hi Dennis:
Yes, for sure.
But, what was he posting that was for sale? (I search on "quadzillatech"... and didn't see anything.)
Curiosity killed this cat (me) along time ago.
Best regards and wishes.
Roy.

Have to evaluate a 494P

Roy Thistle
 

Hi All:
I have to start evaluating a 494P (starting with powering it up).
I've got the docs; but, it's no fun doing it alone (and.. I want to have fun!)
There's posts on the 49xy here... and I've been reading them.
So far, I was able to move it!... without seeing the chiropractor! (A process not recommended... as apparently a 494P is designed to stay in place, in one place.)
I'm more familiar with older analog HP SAs, and some of the newer digital ones... so any discussion would be helpful.
Best regards and wishes to all.
Roy

Items for Sale

 

Hi quadzillatech, and all TekScopes members,

If you are going to post something for sale it is appropriate to indicate your relationship to the seller if there is one,
or if you have no relationship to the seller please say that also.

For example:
"I saw this extremely rare Tektronix scope on Craigs List for $1.00.
It is at this URL ...
I have no relationship to the seller."

Dennis Tillman W7PF

-----Original Message-----
From: quadzillatech@...
Sent: Wednesday, November 13, 2019 4:37 PM
Subject: [TekScopes] nuvistors

https://www.ebay.co.uk/itm/Tektronix-157-0121-00-RCA-7586-nuvistor-NEW-Loc-BB5-04-04/233165715778?hash=item3649c27942:g:ByMAAOSwtOZciPxZ




--
Dennis Tillman W7PF
TekScopes Moderator

Re: Great video for 500 series Tek restorers

Ryan Scott
 

On Wed, Nov 13, 2019 at 16:22, Jamie Ostrowski<jamie.ostrowski@...> wrote:
I wanted to share this video I watched over on youtube. This guy does an absolutely incredible job detailing the internals of the 555 power supply circuitry and also does some work on his own.

It's very thorough! Covers the circuit design and everything.

It's great for beginners such as myself to help us understand what is going on under the hood.

It's obvious a great deal of time and effort went into making the video for Tektronix collectors. Wonderful job...

He has other videos on Tek restorations, but this is the most in-depth.

Thought some other folks here might appreciate this:

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

Re: The best laid plans of mice and men....

Dave Seiter
 

That happened to me at a local auction years ago; I won two pallets of "broken" test equipment, mostly Tek.  The only bidder at $50 each.  Turned out that they had put all the broken stuff on top.  Underneath were functional, almost in cal 7104s, 7488s, etc.  I had a "scopehenge" in my garage for a few months.
-Dave

On Tuesday, November 12, 2019, 06:27:58 PM PST, Vince Vielhaber <vev@...> wrote:

When I buy something on ebay, unless it's new, I buy it with the
assumption and expectation that it don't work.  Its broke.  Period.
That way I'm never disappointed.  I look at a ham radio, and wonder how
much is this broken radio worth to me?  Same thing with any test
equipment.  Is it worth having to fix it?  You'd be surprised at how
many things I've bought over the years that said it didn't work and it
actually did!

Vince.

On 11/12/2019 06:18 PM, Roy Thistle wrote:
Hi Guys:
Great!
It's great to see somebody getting some reasonably good deals from Ebay.
Whenever my ship is in port at Ebay, I always for some strange reason (maybe trauma in my childhood) hear the B-9, Class M-3 say "Danger Will Robinson. Danger!"
Or maybe it is just my wallet moaning from the beating it has taken over the years.
Either way, its safer to assume the worst.... and not hope too much for the best.
Regards and best wishes.
Roy


--
  K8ZW  http://www.metalworkingfun.com   http://www.hamradio.fun

Re: Great video for 500 series Tek restorers

John Williams
 

Thanks Jamie good video. A good explanation of how the indicator unit and the power supply interact through the interconnecting cable.

Re: nuvistors

Greg Muir
 

If you do a "7586 tube" keyword search on the big sales site (eB) you will find dozens and dozens of them including Tek rx-stock versions.

Greg

Great video for 500 series Tek restorers

Jamie Ostrowski
 

I wanted to share this video I watched over on youtube. This guy does an absolutely incredible job detailing the internals of the 555 power supply circuitry and also does some work on his own.

It's very thorough! Covers the circuit design and everything.

It's great for beginners such as myself to help us understand what is going on under the hood.

It's obvious a great deal of time and effort went into making the video for Tektronix collectors. Wonderful job...

He has other videos on Tek restorations, but this is the most in-depth.

Thought some other folks here might appreciate this:

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

Re: Affordable current clamp.

Leo Bodnar
 

I have used Pico's TA018 with good results for 20-30A project https://www.picotech.com/accessories/current-probes-clamps
It was accurate, had long battery life and was reasonably cheap for one-off use.
Leo

nuvistors

quadzillatech@...