?

Hi Chuck

To be honest if I had four pallets of TEK scopes I would break them up for spares as I don't think anyone is going to buy this stuff especially the tube scopes.

The only buyers for old TEK scopes are hobbyists and collectors and those who want a realtime wide bandwidth CRT scope. Technology has moved on, scopes are digital these days with A-D converters sampling at N GHz and all in a cute little box.

I want a scope that works when I switch it on, not with a power supply that goes bzzt, bzzt, tick, tick because some cap has gone short circuit or some corroded part in a socket isn't making contact.

In short, there really isn't much of a market for old TEK scopes.
They were great in their day but not so good 30 or 40 years later.

Best regards
Chris

--- In TekScopes@..., Chuck Harris wrote:
>
> Here's the thing:
>
> I have 4 pallets of tektronix scopes taking up space in my
> warehouse. One pallet is mostly 7000 series, with a few
> 5000 series mainframes, another is a mix of 7000 and 5000
> series rack mount scopes, with a 564. The third is mostly
> 453's, 454's, and a few odd 434, 464, 465, 466, 475, and 485's.
> And the fourth has a 585A, 545A, and 535A on it... the '45
> and '35 were beautiful before the tube whores stripped them...
> but recycler's don't get the luxury of judging, they just take
> what they get.... ixed in with all of this are several large
> boxes of plugins... nothing sexy, but the usual 7B53A's, and
> 7A16, 7A26, 7D14, kind of stuff...
>
> I love cleaning, fixing, calibrating and restoring scopes
> into good working condition. I have all of the Tek specified
> gear for doing this, but judging by ebay sales, buyers don't
> seem to value that effort at all.
>
> To give you an example. I found a DOA 434 in my stash, and
> because it was so cute, I cleaned it up, fixed a power supply
> problem that stumped the original owner, replaced a tantalum
> on one of the boards, fixed a really nasty trigger problem,
> that was caused by the power supply problem, lubed all of the
> pots, cleaned and lubed the panel switches, and fan, cleaned
> the attenuator contacts, and did a complete calibration. It
> took me a week of evenings to do the work. When it was put on
> ebay, as cleaned, calibrated, and guaranteed, it got a couple
> of $15 offers, and it remains unsold... as does its twin that
> I did in hopes of a better result...
>
> At current US scrap prices, I can get $17 per pound for gold
> plated circuit boards, which is the standard price recyclers
> are giving these days... I work with a recycler, so I am very
> sure of these prices... There is easily 2 pounds of circuit
> boards in a 434 [vertical, horizontal, storage, preamps, and
> power supply are all gold plated]. The 453's and 454's have
> easily 5x more...
>
> Considering how much you folks are yipping and yapping about
> tunnel diodes, and how hard they are to find, I could have
> gotten more than $15 if I simply removed the two diodes in
> this 434, and sold them on ebay. And I would still have a
> good CRT, the aluminum from the chassis and can, the gold
> plated circuit boards, a bunch of special IC's, etc... I have
> gotten $5 just from a knob, and $15 from just selling one CRT
> filter!.... to sell.
>
> What's the answer? I keep hearing about how much you guys
> love Tektronix and their scopes, but when one sells for less
> than a tankful of gas, I have to wonder if it is all just
> dreamy nostalgia talk. When a couple of days worth of cleaning,
> repairing, and calibration is worth less than you would pay
> for a dinner out with someone you don't even like all that
> much... Where is the love?
>
> What's it to be? Do I fix them, or Do I scrap them?
>
> What shall I do with these scopes?
>
> -Chuck Harris
>

Here's the thing:

I have 4 pallets of tektronix scopes taking up space in my
warehouse. One pallet is mostly 7000 series, with a few
5000 series mainframes, another is a mix of 7000 and 5000
series rack mount scopes, with a 564. The third is mostly
453's, 454's, and a few odd 434, 464, 465, 466, 475, and 485's.
And the fourth has a 585A, 545A, and 535A on it... the '45
and '35 were beautiful before the tube whores stripped them...
but recycler's don't get the luxury of judging, they just take
what they get.... ixed in with all of this are several large
boxes of plugins... nothing sexy, but the usual 7B53A's, and
7A16, 7A26, 7D14, kind of stuff...

I love cleaning, fixing, calibrating and restoring scopes
into good working condition. I have all of the Tek specified
gear for doing this, but judging by ebay sales, buyers don't
seem to value that effort at all.

To give you an example. I found a DOA 434 in my stash, and
because it was so cute, I cleaned it up, fixed a power supply
problem that stumped the original owner, replaced a tantalum
on one of the boards, fixed a really nasty trigger problem,
that was caused by the power supply problem, lubed all of the
pots, cleaned and lubed the panel switches, and fan, cleaned
the attenuator contacts, and did a complete calibration. It
took me a week of evenings to do the work. When it was put on
ebay, as cleaned, calibrated, and guaranteed, it got a couple
of $15 offers, and it remains unsold... as does its twin that
I did in hopes of a better result...

At current US scrap prices, I can get $17 per pound for gold
plated circuit boards, which is the standard price recyclers
are giving these days... I work with a recycler, so I am very
sure of these prices... There is easily 2 pounds of circuit
boards in a 434 [vertical, horizontal, storage, preamps, and
power supply are all gold plated]. The 453's and 454's have
easily 5x more...

Considering how much you folks are yipping and yapping about
tunnel diodes, and how hard they are to find, I could have
gotten more than $15 if I simply removed the two diodes in
this 434, and sold them on ebay. And I would still have a
good CRT, the aluminum from the chassis and can, the gold
plated circuit boards, a bunch of special IC's, etc... I have
gotten $5 just from a knob, and $15 from just selling one CRT
filter!.... to sell.

What's the answer? I keep hearing about how much you guys
love Tektronix and their scopes, but when one sells for less
than a tankful of gas, I have to wonder if it is all just
dreamy nostalgia talk. When a couple of days worth of cleaning,
repairing, and calibration is worth less than you would pay
for a dinner out with someone you don't even like all that
much... Where is the love?

What's it to be? Do I fix them, or Do I scrap them?

What shall I do with these scopes?

-Chuck Harris

----- Original Message -----

From: Chris

To: TekScopes@...

Sent: Sunday, February 17, 2013 5:40 PM

Subject: [TekScopes] Re: Tektronix 2465 capacitors etc.

?

Thanks! I had actually decided to pull the board and give it a close inspection and wrote down the values, then I had placed the order. Found out when it showed up that I'd ordered the wrong frame size X2 and Y rated capacitors, so I had to place another order of the correct size (had to substitute different mfg's in as they didn't have the one the condor audio pdf listed in stock) Good learning exercise if anything. The only component I didn't replace was the CR1110, dual common-cathode Schottky rectifier.

That said, I soldered everything in, re-assembled the boards and anxiously turned it on, only to find the same problem. Doh. I tested the caps after they were out with my ESR meter that I just built and they all looked acceptable. At least I can say all the caps are new so I won't have to worry about them in the future. I couldn't test the capacitance of a good handful of them as my DMM only works up to 40 micro Farad. Time for a better tester - anyone have a recommendation for a good capacitance meter? I looked at the local radio shack (best electronics store we have around here - read that as the ONLY one..) The Extech (I think it was a model 430) is listed to only 100 micro Farad, so it would still fall short.

So to not get too drawn out, I printed off some sheets from the service manual for the 2465B's: Checking the voltages (1st commandment, thou shalt check voltages right?) I stand as follows:

+10.00v is adjusted to +10.00v
+87v line is giving me about 9.5 volts
+42.4v line is giving me about 7.4 volts
the +15 volt line is giving me 7.2 volts
Digital +5v supply is 4.98volts
Analog +5v supply is 4.58 volts (close, but a tad low and out of spec)
-5V is giving me -4.96v
-8v is -8.01v
-15v is -14.97

So there's a definite problem with the 87, 42.4 and 15 volt lines, and the 5v analog should be looked at. So I've got some more studying to do on the schematics. It looks like for the most part there's an unregulated voltage, and then the regulated voltage, so my plan of attack is to check the unregulated supply voltages first as that can help narrow it down to a supply vs regulator issue.

I got the scope hoping to get into some small circuit design and electronics repair - didn't expect the scope to be the first project. Trial by fire!

So, any tips or pointers are welcome, as well as any recommendations for a good capacitance meter. (I have the BlueESR meter, just assembled their kit this last week - works like a charm)

Thanks!
Chris

--- In TekScopes@..., "random.path" wrote:
>
> Chris -
>
> I have a spreadsheet with parts for refreshing the 2465a LVPS along with Mouser part numbers. This has worked well for my scope. After reading the Condoraudio piece and looking at this list you can decide what you want to do. You can grab the spreadsheet 2465LVPS_ReCap.xls from
> or I can email it directly to you if you can get your email address to me.
>
> Chip
>
>
> --- In TekScopes@..., "Chris" wrote:
> >
> > Hello all,
> > I'll try and keep this short. When it comes to electronics I'm somewhat a newb, but not entirely. I've always been interested in it, and I've recently purchased a scope - the tek 2465 300Mhz unit. Spent some time getting familiar with it, playing around in XY mode, and then used it for some diagnostics with some inductive sensors I was having an issue with. Just when I was getting ready to pack it up from verifying the sensors the scope went a bit goofy. The display at the bottom appeared to be "compressed" to a a central blur (I could change it's intensity with the readout intensity) and my traces were a short line near the center of the screen. I powered the scope off, waited a few seconds and then powered it back on, and it now powers on, lights up all the LED's, and I get a super bright --- display at the center of the screen (unaffected by intensity adjustments etc).
> >
> > So, as typical I pulled the cover and did an initial once-over. I found that on the main power supply board by the mains that 2 of the capacitors look rough (one with the outer shell opened up). If you reference this pdf regarding a 2465B, the 2nd image of the A2 PCB has the very capacitors circles in red. The lower most one in the image is the one that looks like it may have blown. I haven't pulled the board out of the scope to get a better view of it yet. The rest of the capacitors on the board are the green and brown mix as the image in the PDF shows, which leads me to believe they're still the original capacitors in the unit.
> >
> > Now in researching and reading about these scopes before I purchased one, I had read that the capacitors were a common issue in them. I have no worries about un-soldering components and soldering new ones in as I've done it numerous times to revive other old equipment. (And I've read about the need to cool these scopes with a fan if you operate them with the cover off)
> >
> > So sorry to drag this out, so I'll try to make this quick. For those in the know about these scopes, is there a listing/BOM for what capacitors should be purchased and replaced?
> >
> > Does the 2465B use the same values/locations on their boards that I can just follow the PDF I linked?
> >
> > Does my issue sound like something that the capacitors could be causing? Or is it likely more involved?
> >
> > I'd be happy to provide images or video as requested if it will help.
> >
> > A huge thank you for taking the time to read and/or respond!
> > Chris
> >
>

If going to scrap then perhaps a volunteer army in the greater MD area descends on
Chuck's place this spring and removes for posterity the bits of unobotanium, i.e
Knobs, Custom Hybrids, HV transformers and HV Multipliers, and tunnel diodes ?
Microplate CRT's etc.?

Dave
ArtekManuals

where are you located,
i'm in Silverton, oregon
jim


On Feb 17, 2013, at 11:22 AM, Chuck Harris <cfharris@...> wrote:

Ah yes, there is that: If I fire up the forklift,
and take these scopes down from the pallet racks,
unwrap their protective shrink wrap from the pallet,
stand them up individually, and shoot pictures, and
then re stack them and re wrap them with shrink wrap,
start up the forklift, and put them back up on the
pallet racks, I will have spent about 4 hours more
and made my back sore, all on the promise that one
or two of these scopes will receive more than a
scrap value offer.

?

There you go Chuck ..You could be the "seed" for the Tektronix wing at the Smithsonian...it is just down the road ?? :-)

Dave

On 2/17/2013 5:12 PM, Alex wrote:

?

Is there a science museum in your area? Donate the best one and I'm sure that's a tax credit.

-- 
Dave Henderson
Manuals@...

PO Box 175
Welch,MN 55089
651-269-4265

Is there a science museum in your area? Donate the best one and I'm sure that's a tax credit.

--- In TekScopes@..., Chuck Harris <cfharris@...> wrote:

David DiGiacomo wrote:

Well, it seems like you had made up your mind before you posted in the
first place.

But really, what you should do is a make a list, and post it here at
say 25% over the scrap value. Then you won't have to pay any eBay
fees or take the trouble to disassemble things.

If you can't do that much, I don't know why you're a list member.

No, actually I hadn't made up my mind... If I had, I would have
scrapped them and said nothing. That truly would be the easiest,
quickest, and most profitable thing for me to do. Stefan is
completely correct in his assessment.

I'm hoping that someone will be incensed enough at the idea
of these scopes being scrapped that they will make me a real
offer for the scopes, and haul them away.

If you all want a photo of them as they sit on the rack, I'll
get you one right away. I can even lift them out of the rack
and shoot a forklift photo from all sides if that will help
save them from the scrappers...

As to your scolding me for not doing enough... Talk is cheap.
Make an offer and bring a truck.

-Chuck Harris

------------------------------------

Yahoo! Groups Links

David DiGiacomo wrote:

Well, it seems like you had made up your mind before you posted in the
first place.

But really, what you should do is a make a list, and post it here at
say 25% over the scrap value. Then you won't have to pay any eBay
fees or take the trouble to disassemble things.

If you can't do that much, I don't know why you're a list member.

No, actually I hadn't made up my mind... If I had, I would have
scrapped them and said nothing. That truly would be the easiest,
quickest, and most profitable thing for me to do. Stefan is
completely correct in his assessment.

I'm hoping that someone will be incensed enough at the idea
of these scopes being scrapped that they will make me a real
offer for the scopes, and haul them away.

If you all want a photo of them as they sit on the rack, I'll
get you one right away. I can even lift them out of the rack
and shoot a forklift photo from all sides if that will help
save them from the scrappers...

As to your scolding me for not doing enough... Talk is cheap.
Make an offer and bring a truck.

-Chuck Harris

?

Hello--

Dunno whether it's applicable to a 22xx series oscilloscope's
knobs, but I've used the following to remove stubbornly-stuck
knobs without damage.

Attempting to pry off a stuck knob using a screwdriver often
damages the knob or the front panel. Instead, locate a scrap
length of multiconductor ribbon cable (commonly used as
disk-drive cables in PCs).

Using a hobby knife, cut a small slit in the middle of the
cable. Make the slit just wide enough to fit over the knob.

Arrange the ribbon cable such that the conductors contact
each side of the knob's underside. Grasp the ends of the
ribbon cable and pull gently.

The ribbon cable distributes the pulling force more or less
evenly to the knob, minimizing the stresses that would
be applied by prying with a screwdriver.

Hope this helps, and 73--

Brad AA1IP

Chris -

I have a spreadsheet with parts for refreshing the 2465a LVPS along with Mouser part numbers. This has worked well for my scope. After reading the Condoraudio piece and looking at this list you can decide what you want to do. You can grab the spreadsheet 2465LVPS_ReCap.xls from
or I can email it directly to you if you can get your email address to me.

Chip


--- In TekScopes@..., "Chris" wrote:

Hello all,
I'll try and keep this short. When it comes to electronics I'm somewhat a newb, but not entirely. I've always been interested in it, and I've recently purchased a scope - the tek 2465 300Mhz unit. Spent some time getting familiar with it, playing around in XY mode, and then used it for some diagnostics with some inductive sensors I was having an issue with. Just when I was getting ready to pack it up from verifying the sensors the scope went a bit goofy. The display at the bottom appeared to be "compressed" to a a central blur (I could change it's intensity with the readout intensity) and my traces were a short line near the center of the screen. I powered the scope off, waited a few seconds and then powered it back on, and it now powers on, lights up all the LED's, and I get a super bright --- display at the center of the screen (unaffected by intensity adjustments etc).

So, as typical I pulled the cover and did an initial once-over. I found that on the main power supply board by the mains that 2 of the capacitors look rough (one with the outer shell opened up). If you reference this pdf regarding a 2465B, the 2nd image of the A2 PCB has the very capacitors circles in red. The lower most one in the image is the one that looks like it may have blown. I haven't pulled the board out of the scope to get a better view of it yet. The rest of the capacitors on the board are the green and brown mix as the image in the PDF shows, which leads me to believe they're still the original capacitors in the unit.

Now in researching and reading about these scopes before I purchased one, I had read that the capacitors were a common issue in them. I have no worries about un-soldering components and soldering new ones in as I've done it numerous times to revive other old equipment. (And I've read about the need to cool these scopes with a fan if you operate them with the cover off)

So sorry to drag this out, so I'll try to make this quick. For those in the know about these scopes, is there a listing/BOM for what capacitors should be purchased and replaced?

Does the 2465B use the same values/locations on their boards that I can just follow the PDF I linked?

Does my issue sound like something that the capacitors could be causing? Or is it likely more involved?

I'd be happy to provide images or video as requested if it will help.

A huge thank you for taking the time to read and/or respond!
Chris

???

Hi chuck,???

I love the 475, 475a, 485 and the 24xx series. The 7000 would be great but too heavy to ship to Singapore.???

If you could put up a list, and some pictures, we will help to consume them over time.???

I disagree that you scrapped those scopes. That is depriving future generations from the benefits of???

Using those scopes, especially when someone said you do not need the money.???

Gold price is ever rising; future prices may still be higher.???

Scrapping is final; the scopes are gone for ever.???

Cslim

On Monday, February 18, 2013, Patrick Wong wrote:

???

Hi Chuck,

The answer is obvious if your decision is driven by economics: scrap.

Not too many people feel the need to spend a three-digit amount or more, on an obsolete analog scope.

I've listed a fully-operational and calibrated 2467 on eBay for $499 and have not seen any interest. That's the lowest price listed for a working unit of that model - others are trying to get close to $1K or more.

Patrick Wong AK6C

--- In TekScopes@..., Chuck Harris wrote:
>
> ...What's it to be? Do I fix them, or Do I scrap them?
>
> What shall I do with these scopes?