Date   

Re: Tek 2465a grid bias and brightness problems

Francesco
 

Pin 22 and 23 sorry


Re: Tek 2465a grid bias and brightness problems

Francesco
 

Checked pin 22 and 25 of U650 they both changes about 300mv from min to max.


Re: Tek High Amplitude Pulse Generator TM500 manual needed

Albert Otten
 

On Fri, Feb 23, 2018 at 04:43 pm, Ed Breya wrote:


- the average power is pretty small, so the peak or pulse rating of the attenuator
will do, if that spec can be found or determined. I've had no problem using
common 1 or 2 W SMA attenuators - or a whole bunch cascaded to get enough
attenuation. >
Ed
For instance the GR874 fixed attenuators were specified as 1 W cw, 2 kW peak pulsed. 2 kW is more than 300 V / 6 A.
Albert.


Re: 7603 working .... then blank

Roger Evans
 

Ian,

Thanks for taking the time to do this, I really appreciate it.

U973D looks OK for a transistor which is turned ON (I think this might just be a typo). Its base is 0.69V more positive than its emitter and with zero collector load its Vce is small (0.16V with collector more positive)

U973E should be turned OFF, its base is 4.3V negative with respect to its emitter. It has a 180k collector load resistor so with a high impedance voltmeter its collector voltage should read something similar to the +50V supply ie +0.7V. In fact its collector voltage is more negative than its emitter which is distinctly suspicious.

To be absolutely honest, when trying to work out what was happening in the +5V regulator I had temporarily forgotten that +50V on R977 was in fact only +0.7V. I am sure the first thing to do is to find the cause of the overcurrent on +50V. You can isolate the various boards to narrow down the culprit, there is a chain of ribbon cables from regulator board to Zaxis to horizontal amplifier to vertical amplifier, also a ribbon cable from regulator to calibrator board. The +50V sense return from the main board is decoupled by electrolytic capacitor C9 so you may want to check that separately with a multimeter since if you pull the cables to the main board you will lose the sense return on all supplies. If after fixing the +50V you still have a problem with +5V then it might be worth rechcking U973.

Thanks for putting up with me thinking and learning in public.

Roger


Re: Replacing power cords...

Michael A. Terrell
 

Heyco?

-----Original Message-----
From: Bill Riches <@neff1942>
Sent: Feb 23, 2018 8:05 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Replacing power cords...

Not familiar with that scope but could you use one of those black hard plastic strain reliefe clips that grab the cable. Cannot think of the name. I use several sizes and have two weird pliers to squeeze them together to fit in the hole.

73,

Bill, WA2DVU
Michael A. Terrell


Re: Nice source for Tek Manuals

Sebastian Garcia
 

Thank you Stan, this is really good!!

Sebastian.


brasscat wrote:

I have found Archive,org has a huge selection of documents, One major
category is Manuals. In that is a sub category TEKTRONIX section which has
1138 manuals / documents / catalogs. Some of those I have viewed are very
good scans. A lot of 7000 series and 500 series items.

Look in Here ---> https://archive.org/details/manuals_tektronix

Enjoy
Stan




Re: Replacing power cords...

Frank DuVal
 

Lots of house construction tools have flexible cords. Know a contractor who is tossing some old tools with cords? Of course the circular saws will have slashes in the cords...... Ha!

Shop vacuums come to mind. They are always being thrown away broken. Not just the brand name, most any of these (and vacuums for commercial buildings) have three wire flexible cords with grippers. Whereas home vacuums have two wire cords typically.

Frank DuVal

On 2/23/2018 8:00 PM, Dave Daniel wrote:
Phil,

I looked on the web and found lots of power cord pigtails, but none with the "cord grabber", although I am sure that they are out there if the correct search keywords can be found.

I did of one possible source: all of my AC-powered vacuum cleaners use that type of cord with the grabber. Perhaps a local vacuum cleaner repair shop could order one as a repair part for you? Yous have to lop off quite a bit of it since vacuum cleaner cords tend to be very long, but I bet they aren't that expensive. You'd want to pay attention wire size based on the maximum power that the 'scope draws.

DaveD

On 2/23/2018 5:50 PM, Phillip Potter wrote:
Hi all,

My recentl acquisition, a Sony/Tektronics 335 portable, has a stiff, unmanageable power cord. I don't like it. I think power cords should be pliable, resilient, and curl nicely and neatly, so I am thinking about replacing it with a new(er) cord.

What would you replace the power cord with. The original has a plug with a cord grabber and is designed to wrap around the back end of the scope for storage (since it is a portable).

Does anyone have a reference to a nice, supple power cord?

Seems like all of the cheap Chinese cords these days are horribly crunched to save packing space and NEVER straighten out. I recently bought a heat gun for shrink wrap, made in Tiawan, that has the cord from hell. When I unboxed the gun, the cord was a total crunched up mess held by a twist tie, sooo I used the heat gun itself to heat the cable and tried to straighten it, but as it cooled it became the same curly mess it had been. I even tried to hang it to straighten it out... no good.

Well, any recommendations for a good power cable for my portable scope?

Thanks in advance,

Phil


Re: 5L4N Spectrum not Analyzing

Rick
 

I've got a clean 260mV wave at the center tap of T212 at the same 10kHz as the injected signal. The input signal is -15db. As I mentioned earlier I only have this signal when the log/lin cam switch is in only one position. All other switch positions kill the wave to zero. I don't have a signal at the C210 and C213 junction. I'm not quite sure how to take other measurements from the mixer. Seems like the diodes are okay. T218 seems like it should have a signal on it on the way to C210.

Any more ides would be great.

Thanks


Re: Replacing power cords...

Phillip Potter
 

Yeah, Bill, I thought about that when I was looking... found a 40' grounded cord (with cord gripper) shipped for $17... I will have left over cord to also wire the heat gun previously mentioned ;)   then, I will have more left over!

Thanks everybody!

Phil

On 2/23/2018 5:31 PM, n4buq wrote:
Most appliance cords (like a vacuum cleaner) typically have a two-prong cord so beware.

Thanks,
Barry - N4BUQ

----- Original Message -----
From: "Bill Riches" <@neff1942>
To: TekScopes@groups.io
Sent: Friday, February 23, 2018 7:01:52 PM
Subject: Re: [TekScopes] Replacing power cords...

Perhaps an thin IEC cord from a computer or monitor. Home upright vacuum
cleaners have flexible cords - visit your friendly vacuum cleaner repair
store!

73,

Bill WA2DVU
Cape May

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Phillip
Potter
Sent: Friday, February 23, 2018 7:50 PM
To: TekScopes@groups.io
Subject: [TekScopes] Replacing power cords...

Hi all,

My recentl acquisition, a Sony/Tektronics 335 portable, has a stiff,
unmanageable power cord. I don't like it. I think power cords should be
pliable, resilient, and curl nicely and neatly, so I am thinking about
replacing it with a new(er) cord.

What would you replace the power cord with. The original has a plug with a
cord grabber and is designed to wrap around the back end of the scope for
storage (since it is a portable).






Re: Tek High Amplitude Pulse Generator TM500 manual needed

 

Hi Ed,
I forgot about the duty cycle. It is tiny so you are right.
Any of the Tek 2W white male-female 50 ohm terminators will work just fine.
Dennis Tillman W7PF

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Ed Breya via Groups.Io
Sent: Friday, February 23, 2018 4:43 PM
Subject: Re: [TekScopes] Tek High Amplitude Pulse Generator TM500 manual needed

Yes, lots of attenuation is needed to get reasonable levels for equipment testing. The attenuator power rating doesn't have to all that big though - the average power is pretty small, so the peak or pulse rating of the attenuator will do, if that spec can be found or determined. I've had no problem using common 1 or 2 W SMA attenuators - or a whole bunch cascaded to get enough attenuation. BTW if you cascade attenuators in a situation where power may be an issue, put the smaller (lowest dB) ones closest to the source to help spread the power dissipation among them.

Ed




--
Dennis Tillman W7PF
TekScopes Moderator


Re: Replacing power cords...

n4buq
 

Most appliance cords (like a vacuum cleaner) typically have a two-prong cord so beware.

Thanks,
Barry - N4BUQ

----- Original Message -----
From: "Bill Riches" <@neff1942>
To: TekScopes@groups.io
Sent: Friday, February 23, 2018 7:01:52 PM
Subject: Re: [TekScopes] Replacing power cords...

Perhaps an thin IEC cord from a computer or monitor. Home upright vacuum
cleaners have flexible cords - visit your friendly vacuum cleaner repair
store!

73,

Bill WA2DVU
Cape May

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Phillip
Potter
Sent: Friday, February 23, 2018 7:50 PM
To: TekScopes@groups.io
Subject: [TekScopes] Replacing power cords...

Hi all,

My recentl acquisition, a Sony/Tektronics 335 portable, has a stiff,
unmanageable power cord. I don't like it. I think power cords should be
pliable, resilient, and curl nicely and neatly, so I am thinking about
replacing it with a new(er) cord.

What would you replace the power cord with. The original has a plug with a
cord grabber and is designed to wrap around the back end of the scope for
storage (since it is a portable).






Re: Replacing power cords...

Jim Reese
 

Or you local vacuum cleaner trash pile or Walmart/Target dumpster, ha-ha!

Most typical home appliances have fairly flexible cords (dehumidifiers, humidifiers, toasters, blenders, mixers, etc).
When I worked at Kitchenaid, the mixer cords were a silicon based high temp rubber that was really flexible.

If you get your garbage picked up, ask the sanitary engineer to be on the lookout for one in somebody's trash pile.
FYI, I have new flat IEC cords, and probably some round ones that are pretty flexible.  I had offered them on this forum previously.
Regards,
Jim


From: Bill Riches <@neff1942>
To: TekScopes@groups.io
Sent: Friday, February 23, 2018 8:07 PM
Subject: Re: [TekScopes] Replacing power cords...

Hi Dave, Like mimes think alike!

73,

Bill WA2DVU

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Bill Riches
Sent: Friday, February 23, 2018 8:02 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Replacing power cords...

Perhaps an thin IEC cord from a computer or monitor.  Home upright vacuum cleaners have flexible cords - visit your friendly vacuum cleaner repair store!

73,

Bill WA2DVU
Cape May

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Phillip Potter
Sent: Friday, February 23, 2018 7:50 PM
To: TekScopes@groups.io
Subject: [TekScopes] Replacing power cords...

Hi all,

My recentl acquisition, a Sony/Tektronics 335 portable, has a stiff, unmanageable power cord.  I don't like it. I think power cords should be pliable, resilient, and curl nicely and neatly, so I am thinking about replacing it with a new(er) cord.

What would you replace the power cord with.  The original has a plug with a cord grabber and is designed to wrap around the back end of the scope for storage (since it is a portable).


Re: Fan mounts from an old flip-flop

Dave Seiter
 

Grin- for those of us that ship things, we always keep a lookout for material that will work, especially odd sizes. You never know what you'll need!

-Dave

On Feb 23, 2018, at 9:29 AM, stefan_trethan <stefan_trethan@...> wrote:

Well, in return I walked around for a year on the packing material
from a power analyzer.
I don't know where they got that stuff, but it was the perfect
material to cut insoles from, for shoes I really liked but which had
no padding at all.

Probably got more use out of the packing than the analyzer, but hey,
there are people who buy $500 shoes so I guess It's OK since I got the
power analyzer thrown in for free and all.

That was a strange package overall, from over the pond.
It had this sheet of foam, good for a few pairs still, and the rest of
it was stuffed with what felt like TYVEK.
I've got some weird stuff over the years as packing material for ebay
purchases...

ST

On Tue, Feb 20, 2018 at 3:29 PM, Trey Greer <greer@...> wrote:
After a bit of head-scratching, I came up with a decent source of rubber for repairing those old deteriorated fan mounts in 60 year old scopes.

One of my wife's old flip-flops did the trick nicely, with a near perfect match on rubber hardness. Made my day, so I thought I would share.

https://groups.io/g/TekScopes/album?id=28602

-- Trey


Re: Replacing power cords...

Phillip Potter
 

Thanks, Bill and Dave,

Great idea!  I will search out replacement cords for vacuum cleaners!  Awesome.  Why didn't I think of that?!?

BTW, I live in the middle of nowhere and there isn't a vacuum cleaner shop for probably 50 miles or more from here, BUT the internet will provide!

Thanks a bunch!

Phil


Re: Replacing power cords...

Bill Riches
 

Hi Dave, Like mimes think alike!

73,

Bill WA2DVU

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Bill Riches
Sent: Friday, February 23, 2018 8:02 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Replacing power cords...

Perhaps an thin IEC cord from a computer or monitor. Home upright vacuum cleaners have flexible cords - visit your friendly vacuum cleaner repair store!

73,

Bill WA2DVU
Cape May

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Phillip Potter
Sent: Friday, February 23, 2018 7:50 PM
To: TekScopes@groups.io
Subject: [TekScopes] Replacing power cords...

Hi all,

My recentl acquisition, a Sony/Tektronics 335 portable, has a stiff, unmanageable power cord. I don't like it. I think power cords should be pliable, resilient, and curl nicely and neatly, so I am thinking about replacing it with a new(er) cord.

What would you replace the power cord with. The original has a plug with a cord grabber and is designed to wrap around the back end of the scope for storage (since it is a portable).


Re: Replacing power cords...

Bill Riches
 

Not familiar with that scope but could you use one of those black hard plastic strain reliefe clips that grab the cable. Cannot think of the name. I use several sizes and have two weird pliers to squeeze them together to fit in the hole.

73,

Bill, WA2DVU

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Dave Daniel
Sent: Friday, February 23, 2018 8:01 PM
To: TekScopes@groups.io
Subject: Re: [TekScopes] Replacing power cords...

Phil,

I looked on the web and found lots of power cord pigtails, but none with the "cord grabber", although I am sure that they are out there if the correct search keywords can be found.

I did of one possible source: all of my AC-powered vacuum cleaners use that type of cord with the grabber. Perhaps a local vacuum cleaner repair shop could order one as a repair part for you? Yous have to lop off quite a bit of it since vacuum cleaner cords tend to be very long, but I bet they aren't that expensive. You'd want to pay attention wire size based on the maximum power that the 'scope draws.

DaveD

On 2/23/2018 5:50 PM, Phillip Potter wrote:
Hi all,

My recentl acquisition, a Sony/Tektronics 335 portable, has a stiff,
unmanageable power cord. I don't like it. I think power cords should
be pliable, resilient, and curl nicely and neatly, so I am thinking
about replacing it with a new(er) cord.

What would you replace the power cord with. The original has a plug
with a cord grabber and is designed to wrap around the back end of the
scope for storage (since it is a portable).

Does anyone have a reference to a nice, supple power cord?

Seems like all of the cheap Chinese cords these days are horribly
crunched to save packing space and NEVER straighten out. I recently
bought a heat gun for shrink wrap, made in Tiawan, that has the cord
from hell. When I unboxed the gun, the cord was a total crunched up
mess held by a twist tie, sooo I used the heat gun itself to heat the
cable and tried to straighten it, but as it cooled it became the same
curly mess it had been. I even tried to hang it to straighten it
out... no good.

Well, any recommendations for a good power cable for my portable scope?

Thanks in advance,

Phil




Re: Replacing power cords...

Bill Riches
 

Perhaps an thin IEC cord from a computer or monitor. Home upright vacuum cleaners have flexible cords - visit your friendly vacuum cleaner repair store!

73,

Bill WA2DVU
Cape May

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Phillip Potter
Sent: Friday, February 23, 2018 7:50 PM
To: TekScopes@groups.io
Subject: [TekScopes] Replacing power cords...

Hi all,

My recentl acquisition, a Sony/Tektronics 335 portable, has a stiff, unmanageable power cord. I don't like it. I think power cords should be pliable, resilient, and curl nicely and neatly, so I am thinking about replacing it with a new(er) cord.

What would you replace the power cord with. The original has a plug with a cord grabber and is designed to wrap around the back end of the scope for storage (since it is a portable).


Re: Replacing power cords...

Dave Daniel
 

Phil,

I looked on the web and found lots of power cord pigtails, but none with the "cord grabber", although I am sure that they are out there if the correct search keywords can be found.

I did of one possible source: all of my AC-powered vacuum cleaners use that type of cord with the grabber. Perhaps a local vacuum cleaner repair shop could order one as a repair part for you? Yous have to lop off quite a bit of it since vacuum cleaner cords tend to be very long, but I bet they aren't that expensive. You'd want to pay attention wire size based on the maximum power that the 'scope draws.

DaveD

On 2/23/2018 5:50 PM, Phillip Potter wrote:
Hi all,

My recentl acquisition, a Sony/Tektronics 335 portable, has a stiff, unmanageable power cord. I don't like it. I think power cords should be pliable, resilient, and curl nicely and neatly, so I am thinking about replacing it with a new(er) cord.

What would you replace the power cord with. The original has a plug with a cord grabber and is designed to wrap around the back end of the scope for storage (since it is a portable).

Does anyone have a reference to a nice, supple power cord?

Seems like all of the cheap Chinese cords these days are horribly crunched to save packing space and NEVER straighten out. I recently bought a heat gun for shrink wrap, made in Tiawan, that has the cord from hell. When I unboxed the gun, the cord was a total crunched up mess held by a twist tie, sooo I used the heat gun itself to heat the cable and tried to straighten it, but as it cooled it became the same curly mess it had been. I even tried to hang it to straighten it out... no good.

Well, any recommendations for a good power cable for my portable scope?

Thanks in advance,

Phil



Replacing power cords...

Phillip Potter
 

Hi all,

My recentl acquisition, a Sony/Tektronics 335 portable, has a stiff, unmanageable power cord.  I don't like it. I think power cords should be pliable, resilient, and curl nicely and neatly, so I am thinking about replacing it with a new(er) cord.

What would you replace the power cord with.  The original has a plug with a cord grabber and is designed to wrap around the back end of the scope for storage (since it is a portable).

Does anyone have a reference to a nice, supple power cord?

Seems like all of the cheap Chinese cords these days are horribly crunched to save packing space and NEVER straighten out.  I recently bought a heat gun for shrink wrap, made in Tiawan, that has the cord from hell.  When I unboxed the gun, the cord was a total crunched up mess held by a twist tie, sooo I used the heat gun itself to heat the cable and tried to straighten it, but as it cooled it became the same curly mess it had been.  I even tried to hang it to straighten it out... no good.

Well, any recommendations for a good power cable for my portable scope?

Thanks in advance,

Phil


Re: Tek High Amplitude Pulse Generator TM500 manual needed

Ed Breya
 

Yes, lots of attenuation is needed to get reasonable levels for equipment testing. The attenuator power rating doesn't have to all that big though - the average power is pretty small, so the peak or pulse rating of the attenuator will do, if that spec can be found or determined. I've had no problem using common 1 or 2 W SMA attenuators - or a whole bunch cascaded to get enough attenuation. BTW if you cascade attenuators in a situation where power may be an issue, put the smaller (lowest dB) ones closest to the source to help spread the power dissipation among them.

Ed