Date   
Re: Tek 2215

Tothwolf
 

On Sun, 24 Jan 2016, David @DWH [TekScopes] wrote:

The focus resistor chain is just a common point of failure in the early 22xx oscilloscopes and if you have to order parts like the aluminum electrolytic capacitors, it might be worth ordering the resistors and changing them also.
The 18k ohm 1/4W resistor used for the focus control located just in front of the HV multiplier is also problematic. I also replaced a handful of other carbon comp resistors on the preregulator board which had drifted and plan to replace a couple more on the main board with carbon film and metal oxide parts.

I think Tothwolf <tothwolf@...> has a better idea about parts and pricing but we need to know which version of the power supply you have. My guess is that the total cost should be less than $20.
With the price breaks for buying in bulk, the preventative maintenance parts for my 2213 scopes were just under $20.00 per scope. Buying in smaller quantity, based on my old spreadsheets, I suspect the total will be closer to $25.00.

I suppose since these scopes seem to be turning up more often, I should work up a parts list with both Mouser and Digi-Key part numbers.

Re: Tek 2215

Tothwolf
 

On Sun, 24 Jan 2016, David @DWH [TekScopes] wrote:
On Sun, 24 Jan 2016 22:11:50 -0600 (CST), you wrote:
On Sun, 24 Jan 2016, David @DWH [TekScopes] wrote:
On Sun, 24 Jan 2016 18:56:02 -0600 (CST), you wrote:
On Sun, 24 Jan 2016, jasontucker70@... [TekScopes] wrote:

I used new manufacture carbon comp resistors for the 1M ohm resistors, however after the discussion on the list, I picked up some high voltage rated film parts that I plan to replace those with the next time I have the scopes opened up.
The Vishay VR25 and VR35 series high voltage film resistors are very similar if not identical to the high voltage film resistors which Tektronix used to replace the carbon composition resistors originally used in the 22xx series focus chain. They are readily available and inexpensive.
That's what I'm planning to install. I picked up 100 Vishay VR37000001004FR500 for $13.60.
Lol. How many 22xx oscilloscopes are you rebuilding?
So far I've done 3 but I might rebuild one or two more 22xx scopes if I manage to find them cheaply enough. At 6ea for the 3x 2213 scopes I have that's already 18 out of the 100, and as useful as these resistors seem to be, I plan to keep some stock of them in my parts cabinets. For whatever reason the 1% parts were cheaper than the 5% too.

Re: Tek 2215

 

On Sun, 24 Jan 2016 23:02:56 -0600 (CST), you wrote:

On Sun, 24 Jan 2016, David @DWH [TekScopes] wrote:
On Sun, 24 Jan 2016 22:11:50 -0600 (CST), you wrote:
On Sun, 24 Jan 2016, David @DWH [TekScopes] wrote:
On Sun, 24 Jan 2016 18:56:02 -0600 (CST), you wrote:
On Sun, 24 Jan 2016, jasontucker70@... [TekScopes] wrote:

I used new manufacture carbon comp resistors for the 1M ohm
resistors, however after the discussion on the list, I picked up some
high voltage rated film parts that I plan to replace those with the
next time I have the scopes opened up.
The Vishay VR25 and VR35 series high voltage film resistors are very
similar if not identical to the high voltage film resistors which
Tektronix used to replace the carbon composition resistors originally
used in the 22xx series focus chain. They are readily available and
inexpensive.
That's what I'm planning to install. I picked up 100 Vishay
VR37000001004FR500 for $13.60.
Lol. How many 22xx oscilloscopes are you rebuilding?
So far I've done 3 but I might rebuild one or two more 22xx scopes if I
manage to find them cheaply enough. At 6ea for the 3x 2213 scopes I have
that's already 18 out of the 100, and as useful as these resistors seem to
be, I plan to keep some stock of them in my parts cabinets. For whatever
reason the 1% parts were cheaper than the 5% too.
I only have the later 2230 and 2232 models and Tektronix used film
resistors for the focus resistor chain in them.

I would have expected there to be a clean cutoff date for when they
changed resistors in the focus resistor chain but that apparently is
not the case. The 2235, released in 1984, used carbon composition
resistors but the 2236 which was released at the same time used film
resistors and the 2213A and 2215A which were released later, both in
1986, used carbon composition resistors.

There was another resistor change Tektronix made and I think it was
for reliability. The 2213 and 2215 use two 1/2 watt 1% metal film
resistors in series for the collector loads at the output of the
vertical amplifier. These resistors run hot making them unreliable
and were the first 2213/2215 repair that I made and I know of two
other instances where they had to be replaced. The later models used
3 resistors in series for each collector load to distribute the heat
better.

The collector load resistors are not difficult to replace so I would
change them also.

Re: Tek 2215

Tothwolf
 

On Mon, 25 Jan 2016, David @DWH [TekScopes] wrote:

I only have the later 2230 and 2232 models and Tektronix used film resistors for the focus resistor chain in them.

I would have expected there to be a clean cutoff date for when they changed resistors in the focus resistor chain but that apparently is not the case. The 2235, released in 1984, used carbon composition resistors but the 2236 which was released at the same time used film resistors and the 2213A and 2215A which were released later, both in 1986, used carbon composition resistors.
Tektronix revised the type of resistors used in the high voltage divider in the 2213/2215 at least several times too. All of my 2213 scopes are late model scopes which already had the preregulator option installed. None of the scopes appeared to have ever been serviced and these are the resistors I found installed:

B0228xx [scope #2]
R877 - 18K 1/4W carbon film (in spec)
R878, R879, R880, R881, R882, R884 - 1M 1/2W carbon film [red dot on body]

B0229xx [scope #1]
R877 - 18K 1/4W carbon comp (in spec, measured dead on 18K)
R878, R879, R880, R881, R882, R884 - 1M 1/2W carbon comp [standard]

B0233xx [scope #3]
R877 - 18K 1/4W carbon comp (out of spec, measured as 22K)
R878, R879, R880, R881, R882, R884 - 1M 1/2W carbon comp [mil spec]

The B0228xx and B0229xx scopes are only 21 digits apart on their serial
numbers.

There was another resistor change Tektronix made and I think it was for reliability. The 2213 and 2215 use two 1/2 watt 1% metal film resistors in series for the collector loads at the output of the vertical amplifier. These resistors run hot making them unreliable and were the first 2213/2215 repair that I made and I know of two other instances where they had to be replaced. The later models used 3 resistors in series for each collector load to distribute the heat better.

The collector load resistors are not difficult to replace so I would change them also.
Are those the 4 resistors mounted to the board plus the two inline with V+ and V- on the left side of the board in this photo? One of my scopes has one carbon comp and one carbon film for the two inline resistors. I'm planning to replace the two inline resistors with Vishay CCF6015R0FKE36 and the 18K R877 with a Vishay CCF0718K0GKE36. I hadn't planned to replace the 4 resistors on the board, but they look like they might be 1W parts. I've seen photos of these boards where the board is discolored badly from heat around those 4 resistors.

http://strudel.ignorelist.com/~tothwolf/photos/Tektronix_2213/Tektronix_2213_3/1600/IMG_9288.1600.jpg

Re: Recommendations / 2247A

Malcolm Hunter
 

On 25 January 2016 at 00:45, John Dickens jake_117_dickens@...
[TekScopes] <TekScopes@...> wrote:

It would be my first scope with a microprocessor. I also have a 7603 and a
2236 as well, not to mention a 503 in poor shape.

​The 2236 has a 6802 microprocessor, so the 2247A won't be your first. Or
do you mean something else?

Malcolm​

Re: 466 +15 supply and U1724 (1458)

jbaydcoid@...
 

Thanks David for the input. Yes, I was thinking of the .02uf at the input but wrote the 10uf on the output. My bad.

The 65V is around 60V and adjustment is non-reponsive; but that is to be expected since U1724 is not working. No sockets on this board. So I'm going to check the supply to U1724 - R1727 and VR1725 and the U1724 itself.

Re: 466 +15 supply and U1724 (1458)

jbaydcoid@...
 

Thanks Andreas. Will check this one too.

OT: QService components

Malcolm Hunter
 

Hi,

Has anyone else ordered items from QService in Greece? I just received my
first order from them and everything smells of stale tobacco smoke. Is it
just me?

Malcolm

Re: OT: QService components

John Clark
 

No, it's not you. I've found the same smell in the two items I've ordered too. It's pretty bad.

John

Sent from my BlackBerry 10 smartphone.
From: Malcolm Hunter malcolm.r.hunter@... [TekScopes]
Sent: Monday, January 25, 2016 07:01
To: TekScopes@...
Reply To: TekScopes@...
Subject: [TekScopes] OT: QService components


Hi,

Has anyone else ordered items from QService in Greece? I just received my
first order from them and everything smells of stale tobacco smoke. Is it
just me?

Malcolm

Re: OT: QService components

Malcolm Hunter
 

On 25 January 2016 at 12:34, John Clark johnclark05@... [TekScopes]
<TekScopes@...> wrote:

No, it's not you. I've found the same smell in the two items I've ordered
too. It's pretty bad.

​One of the items is a fan for my 2445A. The smell isn't too strong at the
moment - hopefully when it's installed, warmed up and blowing it doesn't
become noticeable. It's not very professional :(

Malcolm​


[Non-text portions of this message have been removed]

Re: OT: QService components

stefan_trethan
 

Lol, we had a very small electronics mail order here, over the years
you could smell how his habit increased.
The man is out of business now.

Better be careful or they'll get you for not paying the import duty on
your tobacco products ;-).

ST

On Mon, Jan 25, 2016 at 1:34 PM, John Clark johnclark05@...
[TekScopes] <TekScopes@...> wrote:
No, it's not you. I've found the same smell in the two items I've ordered too. It's pretty bad.

John

Sent from my BlackBerry 10 smartphone.
From: Malcolm Hunter malcolm.r.hunter@... [TekScopes]
Sent: Monday, January 25, 2016 07:01
To: TekScopes@...
Reply To: TekScopes@...
Subject: [TekScopes] OT: QService components


Hi,

Has anyone else ordered items from QService in Greece? I just received my
first order from them and everything smells of stale tobacco smoke. Is it
just me?

Malcolm










------------------------------------
Posted by: John Clark <johnclark05@...>
------------------------------------


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

Yahoo Groups Links


Re: OT: QService components

Marian B
 

Putting the smelly stuff into a bag with some (cheap!) coffee powder (I
used cheap coffee ground very finely, like espresso, to great success)
for a week or two usually helps.

Pro: Doesn't smell like tobacco anymore
Con: Tends to smell like coffee

Some plastics take longer than others. One of the used Weller tools I
bought took nearly a month in the bag until the silicone cabling didn't
smell like a chainsmoker anymore. Replacing the coffee powder every week
helps, too.

Cheers,
Marian

PS: Yeah, in a town nearby there was also a small electronics shop
operated by someone you could easily confuse for a chain-smoking Gimli.
He was very nice and would always help you troubleshoot circuits and
kits right on his counter. I think he died a few years ago :/

On 25.01.2016 14:06, Stefan Trethan stefan_trethan@... [TekScopes] wrote:


Lol, we had a very small electronics mail order here, over the years
you could smell how his habit increased.
The man is out of business now.

Better be careful or they'll get you for not paying the import duty on
your tobacco products ;-).

ST

On Mon, Jan 25, 2016 at 1:34 PM, John Clark johnclark05@...
[TekScopes] <TekScopes@...> wrote:
No, it's not you. I've found the same smell in the two items I've
ordered too. It's pretty bad.

John

Sent from my BlackBerry 10 smartphone.
From: Malcolm Hunter malcolm.r.hunter@... [TekScopes]
Sent: Monday, January 25, 2016 07:01
To: TekScopes@...
Reply To: TekScopes@...
Subject: [TekScopes] OT: QService components


Hi,

Has anyone else ordered items from QService in Greece? I just received my
first order from them and everything smells of stale tobacco smoke. Is it
just me?

Malcolm










------------------------------------
Posted by: John Clark <johnclark05@...>
------------------------------------


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

Yahoo Groups Links

Re: OT: QService components

Brad Thompson
 

On 1/25/2016 7:00 AM, Malcolm Hunter malcolm.r.hunter@...
[TekScopes] wrote:

Hi,

Has anyone else ordered items from QService in Greece? I just received my
first order from them and everything smells of stale tobacco smoke. Is it
just me?
Hello--

You might try placing the fan in a sealable plastic bag along with some
sheets
of unused fabric softener as used in clothes dryers. Another approach
substitutes
ground coffee (contained in a mesh bag) for the dryer sheets. Buy cheap,
strong,
severely-roasted coffee and discard after a few days. Both methods work with
stinky books.

73--

Brad AA1IP

Re: OT: QService components

n4buq
 

I've ordered from them with no problems. I assume what you got was a spare part pulled from an older piece of gear (as that's a lot of what they sell). I figure they don't take time to clean/restore items like that and the residue is from the item's past life.

Of course, if this were something like a knob, etc., any residue would be fairly easy to remove and a fan might be a bit more difficult. Good luck with it.

Thanks,
Barry - N4BUQ

----- Original Message -----
From: "Malcolm Hunter malcolm.r.hunter@... [TekScopes]" <TekScopes@...>
To: TekScopes@...
Sent: Monday, January 25, 2016 6:42:19 AM
Subject: Re: [TekScopes] OT: QService components

On 25 January 2016 at 12:34, John Clark johnclark05@... [TekScopes]
<TekScopes@...> wrote:

No, it's not you. I've found the same smell in the two items I've ordered
too. It's pretty bad.

​One of the items is a fan for my 2445A. The smell isn't too strong at the
moment - hopefully when it's installed, warmed up and blowing it doesn't
become noticeable. It's not very professional :(

Malcolm​


[Non-text portions of this message have been removed]

Re: Recommendations / 2247A

 

On Mon, 25 Jan 2016 10:18:09 +0000, you wrote:

On 25 January 2016 at 00:45, John Dickens jake_117_dickens@...
[TekScopes] <TekScopes@...> wrote:

It would be my first scope with a microprocessor. I also have a 7603 and a
2236 as well, not to mention a 503 in poor shape.
?The 2236 has a 6802 microprocessor, so the 2247A won't be your first. Or
do you mean something else?

Malcolm?
I almost posted the same thing but decided that he meant
microprocessor controlled.

Re: OT: QService components

 

On Mon, 25 Jan 2016 12:00:48 +0000, you wrote:

Hi,

Has anyone else ordered items from QService in Greece? I just received my
first order from them and everything smells of stale tobacco smoke. Is it
just me?

Malcolm
I noticed the same thing. The strong smell of tobacco reminded me of
my grandfather.

Re: Hello from new member w 2465A issues

Armin Schon
 

Hi David,

You are right, two large paper caps on the AC board have burst open - those were the bangs I heard. The main rectifier caps (in the black plastic holders) seem to be okay. I'll need to research the current limiter you mentioned. In your experience, should I replace all the capacitors like some people have advocated on Youtube or just the two broken ones?

Re: OT: QService components

Malcolm Hunter
 

On 25 January 2016 at 14:01, Barry n4buq@... [TekScopes] <
TekScopes@...> wrote:

I've ordered from them with no problems. I assume what you got was a spare
part pulled from an older piece of gear (as that's a lot of what they
sell). I figure they don't take time to clean/restore items like that and
the residue is from the item's past life.

Of course, if this were something like a knob, etc., any residue would be
fairly easy to remove and a fan might be a bit more difficult. Good luck
with it.
​I received several items, all individually sealed in grip seal bags. They
all have a faint whiff of smoke and the jiffy bag it was shipped in smells
of smoke too. ​I'm not too bothered as long as I it's not too pungent when
the fan is fitted and running. It's just disappointing - not what you
expect from a business these days.

Malcolm


[Non-text portions of this message have been removed]

Re: OT: QService components

Colin Herbert
 

I have also purchased stuff from Qservice. It was a brand-new knob and
didn't smell at all; neither did the Ziplok bag. It turned out to not be the
correct knob, but that's another story...

David, I do hope that you mean that your grandfather was a smoker, not a
humidor! Just joking..

Colin.



From: TekScopes@... [mailto:TekScopes@...]
Sent: 25 January 2016 14:14
To: TekScopes@...
Subject: Re: [TekScopes] OT: QService components





On Mon, 25 Jan 2016 12:00:48 +0000, you wrote:

Hi,

Has anyone else ordered items from QService in Greece? I just received my
first order from them and everything smells of stale tobacco smoke. Is it
just me?

Malcolm
I noticed the same thing. The strong smell of tobacco reminded me of
my grandfather.

Re: 466 +15 supply and U1724 (1458)

 

If the +65 volt supply is actually +60 volts, then that explains why
all of the other supply outputs are slightly low. They all directly
use the +65 volt supply as a reference so there is no mystery there.

Interesting the other half U1724A both inputs are 4.5 should be 8.9. Output 5.1 should be 8.3. And the Vcc is also 4.5. The reference voltage from VR1726 is correct enough at 9.3.
If the output of U1724B was driving Q1752 and Q1756 hard, like 8.8
milliamps hard which is within the output current limit of a 1458,
then Vcc would be pulled down causing problems with the +65 regulator
as well so I think we are looking at a problem with just the +15 volt
regulator. C1757 which you identified is the prime suspect. From the
Tektronix 466 parts list:

10uF 25V 20% 90201 TDC106M025FL Mallory

http://datasheet.octopart.com/TDC475M035NSF-CDE-datasheet-110389.pdf
http://www.cde.com/resources/catalogs/TDC.pdf

I was originally suspicious of a socket but now I think it was Colonel
Mustard, in the Conservatory, with the Candlestick. Err, I mean the
solid tantalum capacitor, in the +15 volt regulator, with a short.

There might be a short somewhere else on the +15 volt supply but
removing C1757 is the place to start. If you have a 10uF to 100uF
aluminum electrolytic capacitor laying around it can be used in its
place.

All voltage measure slightly low but the +15 is way down to 1.4V. Unregulated +15 is slightly high 25.9 vs 22.5 presumably because of no current through pass regulator Q1756.
Is it possible that the 10uf cap to ground at the + input [actually +15 volt output] is bad pulling that input down?
Given the above, this could be the whole problem. A shorted C1757
will pull the +15 volt output down, Q1754 will then limit the current
by pulling the output of U1724B down and that will cause Vcc of U1725B
to be pulled down.

On 25 Jan 2016 03:57:16 -0800, you wrote:

Thanks David for the input. Yes, I was thinking of the .02uf at the input but wrote the 10uf on the output. My bad.

The 65V is around 60V and adjustment is non-reponsive; but that is to be expected since U1724 is not working. No sockets on this board. So I'm going to check the supply to U1724 - R1727 and VR1725 and the U1724 itself.

[Non-text portions of this message have been removed]