Date   

Re: 5xx 'Scopes

Dave Seiter
 

If you search the archive, Stan had some input years ago.  There is an example on ebay now; I think it's also been there for years (no affiliation, etc):
TEKTRONIX R-5030 DUAL BEAM OSCILLOSCOPE * | eBay
I thought I had found one at a local auction years ago, but I'm sure I would have posted a note to that effect, so maybe not.  BTW, I was once on a quest for the dual beams too, but after the 502, R502A, 551 and 555, I decided I no longer had room... (I got 2 pallets of mostly 7K stuff about the time I found the R502A)
-Dave

On Tuesday, August 13, 2019, 08:29:52 PM PDT, <sdturne@q.com> wrote:

On Mon, Aug 12, 2019 at 09:27 PM, Dave Seiter wrote:


What about the (R)5030 and (R)5031?  Ok, they are a little unusual, but they
do turn up from time to time.
-Dave
Not familiar with them. Will have to go read up...

Sean


Re: non-gumming oil

Richard Knoppow
 

I was drawing a blank on the name Oilite, thanks.

On 8/13/2019 2:58 PM, Greg Muir via Groups.Io wrote:
When looking for an answer on an item or problem I usually try to go to the source - the manufacturer. And if I can't find it on the web, I simply call them and talk to an engineer. After all, they usually know best.
http://www.bearing.co.il/OILITE.pdf
https://www.bowman.co.uk/bearings/oilite-bearings-self-lubricating-bearings
And there are others found by Googling.
Greg
--
Richard Knoppow
dickburk@ix.netcom.com
WB6KBL


Re: 5xx 'Scopes

Jim Ford
 

Re: vacuum tube curve tracer - if you ask Dennis Tillman nicely, you may get a copy of his excellent article on the project he did.  (Which in my case will have to wait until retirement to be constructed).Jim Ford Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: sdturne@q.com Date: 8/13/19 8:31 PM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] 5xx 'Scopes On Tue, Aug 13, 2019 at 07:59 AM, Mlynch001 wrote:>> One of the best finds of mine was a very nice Type 576 Curve Tracer (at a> great price). The 576 has indeed helped me repair other equipment. More> importantly, it has greatly increased my understanding of all these little> pieces of black plastic with various wires protruding from the sides.> > --> Michael Lynch> Dardanelle, AR>That's exactly the model I would like to find. The 577 is smaller but lacks the ability to do A-B comparison testing. The 576 can do vacuum tubes too, with the right test fixture if I'm not mistaken.Sean


Re: 5xx 'Scopes

Jim Ford
 

Ooh, mine, too!Jim Ford Sent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: sdturne@q.com Date: 8/13/19 8:30 PM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] 5xx 'Scopes On Tue, Aug 13, 2019 at 07:39 AM, Phillip Potter wrote:>> Sean,> There is a place in Las Cruses, NM, called Edgar Digital Electronics... google> it.> > Gotta run,> Phil>That might be worth a trip down. They have a nice looking Fender twin reverb...guitar amplifiers are another weakness of mine. :o)Sean


Re: 5xx 'Scopes

@0culus
 

On Tue, Aug 13, 2019 at 07:59 AM, Mlynch001 wrote:


One of the best finds of mine was a very nice Type 576 Curve Tracer (at a
great price). The 576 has indeed helped me repair other equipment. More
importantly, it has greatly increased my understanding of all these little
pieces of black plastic with various wires protruding from the sides.

--
Michael Lynch
Dardanelle, AR
That's exactly the model I would like to find. The 577 is smaller but lacks the ability to do A-B comparison testing. The 576 can do vacuum tubes too, with the right test fixture if I'm not mistaken.

Sean


Re: 5xx 'Scopes

@0culus
 

On Tue, Aug 13, 2019 at 07:39 AM, Phillip Potter wrote:


Sean,
There is a place in Las Cruses, NM, called Edgar Digital Electronics... google
it.

Gotta run,
Phil
That might be worth a trip down. They have a nice looking Fender twin reverb...guitar amplifiers are another weakness of mine. :o)

Sean


Re: 5xx 'Scopes

@0culus
 

On Mon, Aug 12, 2019 at 09:27 PM, Dave Seiter wrote:


What about the (R)5030 and (R)5031?  Ok, they are a little unusual, but they
do turn up from time to time.
-Dave
Not familiar with them. Will have to go read up...

Sean


Re: Tek 2465B-CT scope

Tony Fleming
 

Thanks for the information!

On Tue, Aug 13, 2019 at 4:07 PM Chuck Harris <cfharris@erols.com> wrote:

Last CT problem I fixed was due to a bad trigger hybrid
in the scope. The trigger hybrid has to be extra especially
good for the CT option to work. It is the beginning and
the end of all counter timer operations. The weakest link,
as it were.

-Chuck Harris

Dwayne Reid wrote:
Good day to all.

I recently acquired a Tek 2465BCT (GPIB option) that has some problems.

The first problem is a diagnostic error on power-up: (I think) 06 02
This was
displayed the first couple of times that I powered the scope up but
hasn't happened
since. Unfortunately, I assumed the error would always come up every
time I powered
the scope ON, so didn't take a picture of the screen. Oops.

The second problem is that the sweep collapses / goes wonky for a second
or two after
several minutes of operation. Again - happened a couple of times but
hasn't happened
since.

Third problem showed up this morning: CT TEST 84 FAIL 0C This time I
did take a
picture of the screen <grin>.

I haven't done any other checking on this unit. Yet.

I'm hoping that others more knowledgeable than myself can tell me what
the potential
issues are. I am assuming that the first error message relates to weak
or dead
battery for the calibration constants.

I'll look at doing some of the work myself but rather than trying to fix
major
problems myself, I'm thinking of sending it off to someone to have them
check it out,
do any repairs necessary, replace all capacitors that are known to fail
over time.
I've used a fellow named Alexander Schonfeld in the past - he seems to
do good work
but I'm open to other suggestions for other people.

Many thanks!

dwayne



Full 7503 manual online anywhere?

Dave Seiter
 

My second 7503, which I thought was completely dead, is actually showing signs of life.  It has a P11 CRT, which is fairly dim at max intensity, and activity can only be seen with the beam finder pulled out.  Mechanically, the scope looks like it had a bad day at some point in it's life...
Are the schematics anywhere online for this scope?  All the manuals I've found so far are copies of the 96 page version, which is missing everything after the description of the readout system.
-Dave


Re: non-gumming oil

greenboxmaven
 

Ultrasonic cleaning is a very good way to get the crud out of sintered bearings. Now that analog turtables and tape recorders are being sought and used again, some AudioPhool boutiques gush about their multi-step ultrasonic cleaning and re-oiling process for motors. Many of those same boutiques are eager to find and use classic Tektronix scopes and Hewlett-Packard signal generators and distortion analyzers. They are also the ones who search for 5XX models at hamfests, take out all of the tubes and the power transformer(s), and throw the rest in the dumpster.

Bruce Gentry, KA2IVY

On 8/13/19 7:13 PM, Ken Eckert wrote:
I wonder if ultrasonic cleaning would help before relubricating, assuming
the bearing can be removed.....

On Tuesday, August 13, 2019, Bob Albert via Groups.Io <bob91343=
yahoo.com@groups.io> wrote:

One can indeed relubricate a sintered 'lifetime' bearing. I have been
successful doing it.
The preferred method, time intensive, is to remove the bearing and soak it
in oil for a day or two. It will eventually take in enough oil to allow it
to operate for a very long time.
Another, less effective, method is to drizzle oil on the bearing
repeatedly, like three times a day at first and then once a day. When it
doesn't dry up any more, it should be good to go.
Once you reinstall them, use urdinary lubricating procedure to make sure
they are going well. After having done that, you can leave them alone.
However, if they have been run dry for too long, the pores may have closed
up and won't take on fresh oil. When a bearing starts to make noise, it's
wise to take it out of service. And ignore the 'lifetime' appelation; oil
them now and then.
On Tuesday, August 13, 2019, 02:22:15 PM PDT, Richard Knoppow <
dickburk@ix.netcom.com> wrote:

I am not so sure about what additives there are in engine
oil. One can get good quality SAE 20 machine oil at many hardware
stores. 3-in-one puts it up in a blue can (red can is something
else). Also as Kano Microil, very highly refined petroleum based
oil, wax free, and does not gum. Most of these blower bearings
are so called "life time lubricated" meaning it works until it
doesn't. They are made from sintered bronze with oil held in the
spongy metal. You can't really re-lubricate them in any easy way
but they will hold oil for a reasonable time.
Hewlett-Packard used blowers with a rubber seal at one end.
They could be re-lubricated using a syringe to poke through the
seal and inject some oil. I have no idea if the Tek blowers are
similar. Unfortunately, once the bearings run dry they will
become galled and run rough despite having new lubricant.
I agree with you that mixing silicon oil or grease with
petroleum lubricant is not a good idea.

On 8/13/2019 2:03 PM, Chuck Harris wrote:
Why?

Silicone oil isn't miscible with the original oil, and
you are not going to make the motor become maintenance
free, no matter what you do with oils.

Just give it some motor oil, thin like SAE5 or 10 is fine.
Detergent isn't like the stuff you wash your clothes in,
it will not cause any problems, in spite of its suggestive
name.

The synthetic doesn't oxidize as quickly as the old oil
did, but then any modern oil is much better in that regard.

The last time anyone lubed your scope fan was likely 40
years ago and yet, it still works. Give it a couple of
drops of oil, and move on... be happy!

-Chuck Harris

Stephen Hanselman wrote:
I've read some of the answers and wanted to add my two cents. We use
marvel
mystery oil which seems ok so far. I was thinking about using silicon
based
gun oil though

steve
--
Richard Knoppow
dickburk@ix.netcom.com
WB6KBL







Re: non-gumming oil

Ken Eckert
 

I wonder if ultrasonic cleaning would help before relubricating, assuming
the bearing can be removed.....

On Tuesday, August 13, 2019, Bob Albert via Groups.Io <bob91343=
yahoo.com@groups.io> wrote:

One can indeed relubricate a sintered 'lifetime' bearing. I have been
successful doing it.
The preferred method, time intensive, is to remove the bearing and soak it
in oil for a day or two. It will eventually take in enough oil to allow it
to operate for a very long time.
Another, less effective, method is to drizzle oil on the bearing
repeatedly, like three times a day at first and then once a day. When it
doesn't dry up any more, it should be good to go.
Once you reinstall them, use urdinary lubricating procedure to make sure
they are going well. After having done that, you can leave them alone.
However, if they have been run dry for too long, the pores may have closed
up and won't take on fresh oil. When a bearing starts to make noise, it's
wise to take it out of service. And ignore the 'lifetime' appelation; oil
them now and then.
On Tuesday, August 13, 2019, 02:22:15 PM PDT, Richard Knoppow <
dickburk@ix.netcom.com> wrote:

I am not so sure about what additives there are in engine
oil. One can get good quality SAE 20 machine oil at many hardware
stores. 3-in-one puts it up in a blue can (red can is something
else). Also as Kano Microil, very highly refined petroleum based
oil, wax free, and does not gum. Most of these blower bearings
are so called "life time lubricated" meaning it works until it
doesn't. They are made from sintered bronze with oil held in the
spongy metal. You can't really re-lubricate them in any easy way
but they will hold oil for a reasonable time.
Hewlett-Packard used blowers with a rubber seal at one end.
They could be re-lubricated using a syringe to poke through the
seal and inject some oil. I have no idea if the Tek blowers are
similar. Unfortunately, once the bearings run dry they will
become galled and run rough despite having new lubricant.
I agree with you that mixing silicon oil or grease with
petroleum lubricant is not a good idea.

On 8/13/2019 2:03 PM, Chuck Harris wrote:
Why?

Silicone oil isn't miscible with the original oil, and
you are not going to make the motor become maintenance
free, no matter what you do with oils.

Just give it some motor oil, thin like SAE5 or 10 is fine.
Detergent isn't like the stuff you wash your clothes in,
it will not cause any problems, in spite of its suggestive
name.

The synthetic doesn't oxidize as quickly as the old oil
did, but then any modern oil is much better in that regard.

The last time anyone lubed your scope fan was likely 40
years ago and yet, it still works. Give it a couple of
drops of oil, and move on... be happy!

-Chuck Harris

Stephen Hanselman wrote:
I've read some of the answers and wanted to add my two cents. We use
marvel
mystery oil which seems ok so far. I was thinking about using silicon
based
gun oil though

steve
--
Richard Knoppow
dickburk@ix.netcom.com
WB6KBL







Re: General Radio 874 Connector, inner conductor "bendies"

Bill Morton
 

On Aug 13, 2019, at 08:11, Dennis Tillman W7PF <dennis@ridesoft.com> wrote:

Hi Dave,

Remember Tek gold plated their PC boards until gold skyrocketed in in price in 1972 or 1973 so I think it was an easy way for Tek to "color code" the adapters so engineers would know which way to connect them. It is definitely not solid gold. Even an idiot could tell that by the weight. There would be a very big difference in mass from the non-gold end to the gold end if it were solid gold.

Dennis

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dave Seiter
Sent: Monday, August 12, 2019 4:41 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] General Radio 874 Connector, inner conductor "bendies"

Hi Dennis,
Yes, the inner conductor for the 125ohm version is considerably smaller than the normal version. I've always wondered if there was another use for them because some of the people selling them think they are made from pure gold (apparently). The box that's on ebay now has been there since at least 2008. When I was actively looking for them, they were easy to spot from far away at swap meets due to the gold. If there was a bin of 874s, I always did a quick scan of all of them because just as you occasionally run across a "normal" 874 that is gold plated, I have found 125 ohm versions that are not gold plated. (I have a "T" connector sitting on the couch next to me which has no gold at all, even though all three ends are 125 ohm). Also, the oldest 519 I have has no gold plated connectors at all. Seems odd to use gold plating as a visual key, but I guess if you're buying a 519, it's nice to have some bling instead of colored plastic.
-Dave

On Monday, August 12, 2019, 09:40:29 AM PDT, Dennis Tillman W7PF <dennis@ridesoft.com> wrote:

Hi Dave,
If I remember correctly the reason for the 125 ohm connectors was because that was the impedance of the vertical deflection plates. The input signal went directly to the plates. So I would guess the answer is no - there was no other use for 125 ohm connectors

To get 125 ohm characteristic impedance the size of the inner conductor has to be different than for a 50 ohm characteristic impedance so Tek made special 50 ohm to 125 ohm adapters. The 50 ohm GR 874 connector was on one end and the 125 ohm GR connector was at the other end. The 50 ohm end was the standard color of all GR connectors. The 125 ohm end was plated with gold. Because of the gold they were quite eye catching and "unique". The entire set of adapters Tek made for the 519 came in a really beautiful mahogany box. I had one of those boxes with most of the 519 adapters. The box, the adapters, and the 519 are now in Barrie Gilbert's collection of scopes.

Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dave Seiter
Sent: Monday, August 12, 2019 9:03 AM

Speaking of the 874 connectors, were the 125 ohm versions ever used for anything unrelated to the 519s, or by anyone outside of Tek?
-Dave


On Sunday, August 11, 2019, 05:12:44 PM PDT, Dale H. Cook <bridgewaterma@plymouthcolony.net> wrote:

On 8/11/2019 4:08 PM, Bruce Hunter wrote:

The 774-series connectors were the predecessors of the 874-type and best described as a banana plug encased with an outer shield. They were not hermaphroditic.


--
Dennis Tillman W7PF
TekScopes Moderator







--
Dennis Tillman W7PF
TekScopes Moderator



Re: Is an early 7A26 a keeper?

Carsten Bormann
 

On Aug 13, 2019, at 00:24, Dennis Tillman W7PF <dennis@ridesoft.com> wrote:

I stumbled across a web page where the author showed how easy it was to make your own 5K X100 probes that could be soldered in place.
Still have a link?
(I know the fundamentals, but a ready-to-use recipe would be great.)

Grüße, Carsten


Re: non-gumming oil

Bob Albert
 

One can indeed relubricate a sintered 'lifetime' bearing. I have been successful doing it.
The preferred method, time intensive, is to remove the bearing and soak it in oil for a day or two.  It will eventually take in enough oil to allow it to operate for a very long time.
Another, less effective, method is to drizzle oil on the bearing repeatedly, like three times a day at first and then once a day.  When it doesn't dry up any more, it should be good to go.
Once you reinstall them, use urdinary lubricating procedure to make sure they are going well.  After having done that, you can leave them alone.
However, if they have been run dry for too long, the pores may have closed up and won't take on fresh oil.  When a bearing starts to make noise, it's wise to take it out of service.  And ignore the 'lifetime' appelation; oil them now and then.

On Tuesday, August 13, 2019, 02:22:15 PM PDT, Richard Knoppow <dickburk@ix.netcom.com> wrote:

    I am not so sure about what additives there are in engine
oil. One can get good quality SAE 20 machine oil at many hardware
stores. 3-in-one puts it up in a blue can (red can is something
else). Also as Kano Microil, very highly refined petroleum based
oil, wax free, and does not gum. Most of these blower bearings
are so called "life time lubricated" meaning it works until it
doesn't. They are made from sintered bronze with oil held in the
spongy metal. You can't really re-lubricate them in any easy way
but they will hold oil for a reasonable time.
    Hewlett-Packard used blowers with a rubber seal at one end.
They could be re-lubricated using a syringe to poke through the
seal and inject some oil. I have no idea if the Tek blowers are
similar.  Unfortunately, once the bearings run dry they will
become galled and run rough despite having new lubricant.
    I agree with you that mixing silicon oil or grease with
petroleum lubricant is not a good idea.

On 8/13/2019 2:03 PM, Chuck Harris wrote:
Why?

Silicone oil isn't miscible with the original oil, and
you are not going to make the motor become maintenance
free, no matter what you do with oils.

Just give it some motor oil, thin like SAE5 or 10 is fine.
Detergent isn't like the stuff you wash your clothes in,
it will not cause any problems, in spite of its suggestive
name.

The synthetic doesn't oxidize as quickly as the old oil
did, but then any modern oil is much better in that regard.

The last time anyone lubed your scope fan was likely 40
years ago and yet, it still works.  Give it a couple of
drops of oil, and move on... be happy!

-Chuck Harris

Stephen Hanselman wrote:
I've read some of the answers and wanted to add my two cents.  We use marvel
mystery oil which seems ok so far.  I was thinking about using silicon based
gun oil though

steve
--
Richard Knoppow
dickburk@ix.netcom.com
WB6KBL


Re: non-gumming oil

Greg Muir
 

When looking for an answer on an item or problem I usually try to go to the source - the manufacturer. And if I can't find it on the web, I simply call them and talk to an engineer. After all, they usually know best.

http://www.bearing.co.il/OILITE.pdf
https://www.bowman.co.uk/bearings/oilite-bearings-self-lubricating-bearings

And there are others found by Googling.

Greg


Re: non-gumming oil

Richard Knoppow
 

I am not so sure about what additives there are in engine oil. One can get good quality SAE 20 machine oil at many hardware stores. 3-in-one puts it up in a blue can (red can is something else). Also as Kano Microil, very highly refined petroleum based oil, wax free, and does not gum. Most of these blower bearings are so called "life time lubricated" meaning it works until it doesn't. They are made from sintered bronze with oil held in the spongy metal. You can't really re-lubricate them in any easy way but they will hold oil for a reasonable time.
Hewlett-Packard used blowers with a rubber seal at one end. They could be re-lubricated using a syringe to poke through the seal and inject some oil. I have no idea if the Tek blowers are similar. Unfortunately, once the bearings run dry they will become galled and run rough despite having new lubricant.
I agree with you that mixing silicon oil or grease with petroleum lubricant is not a good idea.

On 8/13/2019 2:03 PM, Chuck Harris wrote:
Why?
Silicone oil isn't miscible with the original oil, and
you are not going to make the motor become maintenance
free, no matter what you do with oils.
Just give it some motor oil, thin like SAE5 or 10 is fine.
Detergent isn't like the stuff you wash your clothes in,
it will not cause any problems, in spite of its suggestive
name.
The synthetic doesn't oxidize as quickly as the old oil
did, but then any modern oil is much better in that regard.
The last time anyone lubed your scope fan was likely 40
years ago and yet, it still works. Give it a couple of
drops of oil, and move on... be happy!
-Chuck Harris
Stephen Hanselman wrote:
I've read some of the answers and wanted to add my two cents. We use marvel
mystery oil which seems ok so far. I was thinking about using silicon based
gun oil though

steve
--
Richard Knoppow
dickburk@ix.netcom.com
WB6KBL


Re: Tek 2465B-CT scope

Chuck Harris
 

Last CT problem I fixed was due to a bad trigger hybrid
in the scope. The trigger hybrid has to be extra especially
good for the CT option to work. It is the beginning and
the end of all counter timer operations. The weakest link,
as it were.

-Chuck Harris

Dwayne Reid wrote:

Good day to all.

I recently acquired a Tek 2465BCT (GPIB option) that has some problems.

The first problem is a diagnostic error on power-up: (I think) 06 02 This was
displayed the first couple of times that I powered the scope up but hasn't happened
since. Unfortunately, I assumed the error would always come up every time I powered
the scope ON, so didn't take a picture of the screen. Oops.

The second problem is that the sweep collapses / goes wonky for a second or two after
several minutes of operation. Again - happened a couple of times but hasn't happened
since.

Third problem showed up this morning: CT TEST 84 FAIL 0C This time I did take a
picture of the screen <grin>.

I haven't done any other checking on this unit. Yet.

I'm hoping that others more knowledgeable than myself can tell me what the potential
issues are. I am assuming that the first error message relates to weak or dead
battery for the calibration constants.

I'll look at doing some of the work myself but rather than trying to fix major
problems myself, I'm thinking of sending it off to someone to have them check it out,
do any repairs necessary, replace all capacitors that are known to fail over time.
I've used a fellow named Alexander Schonfeld in the past - he seems to do good work
but I'm open to other suggestions for other people.

Many thanks!

dwayne


Re: non-gumming oil (was: 547 Fan lubrication) OT

Chuck Harris
 

Why?

Silicone oil isn't miscible with the original oil, and
you are not going to make the motor become maintenance
free, no matter what you do with oils.

Just give it some motor oil, thin like SAE5 or 10 is fine.
Detergent isn't like the stuff you wash your clothes in,
it will not cause any problems, in spite of its suggestive
name.

The synthetic doesn't oxidize as quickly as the old oil
did, but then any modern oil is much better in that regard.

The last time anyone lubed your scope fan was likely 40
years ago and yet, it still works. Give it a couple of
drops of oil, and move on... be happy!

-Chuck Harris

Stephen Hanselman wrote:

I've read some of the answers and wanted to add my two cents. We use marvel
mystery oil which seems ok so far. I was thinking about using silicon based
gun oil though

steve


Re: Is an early 7A26 a keeper?

John
 

In reply to Dennis's comment about the 1/2 scale reading. I checked the output from the input stage going into U1350 on Channel 1 and it is the same on both channels so I don't think it is in the input switching. Anyway I am going to build up an extender and one day (see there it comes again, you know that one day that never seems to come around) we'll get stuck into it and figure out what is going wrong.

John Proctor
VK2DLP


Re: Is an early 7A26 a keeper?

Jim Ford
 

Yes, I know that Someday very well! ;)Jim FordSent from my Verizon, Samsung Galaxy smartphone

-------- Original message --------From: John <john.d@theproctors.net.au> Date: 8/13/19 1:53 PM (GMT-08:00) To: TekScopes@groups.io Subject: Re: [TekScopes] Is an early 7A26 a keeper? Folks, I am sorry that I seemed to hijack this posting but thanks for the information. I can see where a passive 50 ohm probe might have been useful in my current HP 8662A resurrection job. One place that was particularly troublesome was in one of the VCOs which was tuned by 10 parallel connected varacaps. It would oscillate sometimes and other times it was dead. When it did oscillate it would sometimes go free run with many spurs. I was going towards the JFET having gone slightly tropo but it was solved with a replacement module which came up at a good price. Someday I'll get back to it (you know that some day which never comes). Thanks for the input and I'll keep my eyes open for something like a P6056 or P6057. The problem is that most eBay sellers have lost the plot on pricing. Once again thanks for the advice.John ProctorVK2DLP

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