Date   
Re: Type 503 Oscilloscope Issues

Evan
 

I am not sure if I am taking the ripple readings correctly. The 503 manual states to start with 10mV/cm and 5 ms/cm as the settings, but these result in a large, curved, blurred wave. Going with John's instructions, the largest setting for the vertical adjustment is 20 V/cm. From this, only when turned to at least 200 mV/cm do any distinct waves appear. However, as the voltage range is decreased, the overall wave becomes more distorted (curved). Adjusting the sweep to a smaller time/cm, the wave distortion is lessened (appears as a straight line than a curve). However, I had to adjust the sweep magnification to make out the individual peaks.

The photos are here: https://goo.gl/photos/nB3jfvqa3o7BqGR19 https://goo.gl/photos/nB3jfvqa3o7BqGR19. I only checked the -100 V bus. The knob settings should be visible in the photos (except for the sweep in some, since blocked). The lowest sweep setting I set was 0.2 ms/cm. Also, although the waves in the photos appear to be stable, they fluctuated a lot (several waves on top of each other).


The waves present do not seem typical of those for an AC ripple, even when considering the issues with the scope, so I will still check the measurements with the external scopes later.


- Evan

Re: 7S14 with not working CH2

Roger Evans
 

Some of your older pictures hinted at a periodic structure to the noise. You may be able to reveal this by adjusting the holdoff control and the trigger options.

You might also confirm that the noise is constant in mVolt when you change the vertical sensitivity, including exercising the variable control. Also is the noise constant when you move the trace from the top to the bottom of the screen?

Roger

Re: Type 503 Oscilloscope Issues

ykochcal
 

Second email (never know what goes through when)

The P6053B is listed as 500 V (dc + peak ac) to 3.5 MHz; so that may work
with the other scopes like the HP 54600 but I would not use it for looking
at the +500V but the -100 is in i'ts range. There are some capacitance
matching/rise time issues with probes but I don't think that is a key issue
yet in getting some useful info on basic power supply status

John

-----Original Message-----
From: TekScopes@... [mailto:TekScopes@...]
Sent: Tuesday, May 09, 2017 4:52 PM
To: TekScopes@...
Subject: [TekScopes] Re: Type 503 Oscilloscope Issues

Below is a link to the probes and scopes I have available:
https://goo.gl/photos/LEyMqDkCLHuVXpry9
https://goo.gl/photos/LEyMqDkCLHuVXpry9



In short, all of the probes are Tektronix make.


The probe I have with the 503 is P6027 (1X, 1 Mohm, 67 pF). It does not
state any specifics on voltages, but from the manual on Checking Power
Supply Ripple, this is the correct probe to use for all but the -3000 V
(since the scope cannot handle that).


As for the other probes, I have two different 10 X probes (P6053B, 10 Mohm,
9.5 pF, and P6008, 10 Mohm, 7 pF). I also have another 1X probe (P6028, 30
pF). These all have the BNC connector, but I have several UHF to BNC
adapters, so they could be used with my 503 as well.


As for the scopes available for use, there are HP 54600B (100 MHz), HP
54502A (400 Mhz), and Agilent Tech MSO6012A (100 Mhz).


- Evan








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Posted by: enchanter464@...
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Yahoo Groups Links

Re: Type 503 Oscilloscope Issues

ykochcal
 

That's progress

The P6027 which is like a P6028 (different connector) I don't see a spec
sheet for but is listed on

<http://www.reprise.com/host/tektronix/reference/voltage_probes.asp>

As rated for 600V DC 600V AC so that should work even as a 1X it would be
better to check AC ripple.


And the P6008 is a tube scope vintage probe, and has the specs at
<http://w140.com/tekwiki/wiki/P6008>

And page 1-1 states max DC or AC peak to Peak below 20Mhz: 600V. De-rate
above.

The oscillator in the power supply is in the 15-30Khz range.

So stick that adapter on, and then the probe and connect to -100V buss.

Set for AC input and start at about 50V/Div (knob at 5V/Div with the 10 to 1
probe), Power up

And then turn down to lower voltages vertical as needed.

Look at both at a sweep for 15-30Khz range to see the oscillator cycles

And then a sweep for 60Hz with a line sync if there is one to see if there
is any issue with the 500V supply ripple coming through.

Keep in mind the scope is not "working" so a picture of the two results
would be helpful to see what useful information it might show.

John

-----Original Message-----
From: TekScopes@... [mailto:TekScopes@...]
Sent: Tuesday, May 09, 2017 4:52 PM
To: TekScopes@...
Subject: [TekScopes] Re: Type 503 Oscilloscope Issues

Below is a link to the probes and scopes I have available:
https://goo.gl/photos/LEyMqDkCLHuVXpry9
https://goo.gl/photos/LEyMqDkCLHuVXpry9



In short, all of the probes are Tektronix make.


The probe I have with the 503 is P6027 (1X, 1 Mohm, 67 pF). It does not
state any specifics on voltages, but from the manual on Checking Power
Supply Ripple, this is the correct probe to use for all but the -3000 V
(since the scope cannot handle that).


As for the other probes, I have two different 10 X probes (P6053B, 10 Mohm,
9.5 pF, and P6008, 10 Mohm, 7 pF). I also have another 1X probe (P6028, 30
pF). These all have the BNC connector, but I have several UHF to BNC
adapters, so they could be used with my 503 as well.


As for the scopes available for use, there are HP 54600B (100 MHz), HP
54502A (400 Mhz), and Agilent Tech MSO6012A (100 Mhz).


- Evan








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Posted by: enchanter464@...
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Yahoo Groups Links

Re: 468 with no -2459 v

Samuel Rocha <py1dkw@...>
 

To the group,
My 468 showed the  following measurements:no -2450 VPower supply test points:110v - 110,8v5v - 6,75v ( out of specs)+15v - +15vHV white fuse and +23v fuses are good.Transistor Q1108 ( power HV transistor) - base = -6,6, collector=23vQ530 tested good, but base is 1,61 volts instead of -0,7v, Next I will check R1431 high value resistors.
I would be glad to knw where can I buy the high values resistors for HV also the blue acrylic screen ( if someone has a spare one and want to sell me...I would be very grateful).
So, I am waiting for the 1kpF/6 kv capacitors to arrive to build another multiplier.
Again, would like to thanks everybody concerning this matter,Sam Py1dkw 

Enviado do Yahoo Mail. Baixe o aplicativo

Em Sexta-feira, 5 de Maio de 2017 13:33, "Paul Amaranth paul@... [TekScopes]" <TekScopes@...> escreveu:


  I had #1 happen to me on a 468 except it was an intermittent.
Drove me crazy trying to track that down. There was a hairline
crack at the ceramic body that was impossible to see until it
was removed.

Paul

On Fri, May 05, 2017 at 12:29:31PM -0400, Chuck Harris cfharris@... [TekScopes] wrote:
Additional places to look:

1) the hybrid resistor gets dirty with HV attracted
smutz, which can make it vary the HV from spec
(not likely here). It can also go open circuit
where the terminal clips are soldered to the
silver terminals on the ceramic... especially if
someone has tried to straighten it.
2) C629, a 5ufuf tantalum tends to get leaky or short.
3) C531, a .22uf tends to get leaky or short.
4) Q1108 is socketed, cabled, and further socketed.
5) C108 47uf is a tantalum that tends to blow the HV
fuse when it shorts.
6) L107 is an RFC that tends to blow, protecting the
HV fuse...

To tell you much more will require that you tell us:

1) is the HV oscillator running (TP112)
2) is the HV voltage gone, or low.
3) are the 110V, 5V, 15V supplies good, proper amounts
of ripple, and in specification?
4) is HV oscillator fuse good?

-Chuck Harris

David @DWH [TekScopes] wrote:
"I took the faulty multiplier, but still no -2450 volts." - What does
that mean?

Where is the unregulated +15 volt supply good? Is fuse F809 which
protects the high voltage inverter blown?

Is there any oscillation at the collector of Q1108? What is the
voltage at the collector of Q1108?

What are the voltages at the pins of Q530?

Everything above is shown on schematic 11.

On Fri, 5 May 2017 11:38:32 +0000 (UTC), you wrote:

To the Group,After had repaired my 465, I turned my efforts in order to repair a 468 with no -2450 v.
The scope was running,but after some minutes the HV went down. I took the faulty multiplier, but still no -2450 v. The 23v supplies is good. Where should I start looking?Many thanks and a Nice weekend to ALL.Sam

Enviado do Yahoo Mail no Android

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Posted by: David <@DWH>
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Yahoo Groups Links




!DSPAM:590ca6c6224431846820537!
--
Paul Amaranth, GCIH | Rochester MI, USA
Aurora Group, Inc. | Security, Systems & Software
paul@... | Unix & Windows

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

Re: Need 545B HV Transformer Rewound

vollumscope <perls@ime.net>
 

Howdy Chuck-

Call that two orders for your HV trans rewinding service. I've got a 547 with the "HV syndrome".

LMK when you're ready to do the re-winds. I'm in no particular hurry either but certainly this year.


Regards,

Vollumscope.

Re: 575 curve tracer on UK eBay

Tom Jobe <tomjobe@...>
 

It will be interesting to hear what Steve Ripper has to say about the
very nice looking handles on his 575.

What I did with my 575's was buy the slightly later style 500 series
handle bar that uses two handles with plastic grips.
The complete handle bar will not fit the 575, but the mounting hole
pattern for later style handles will make the newer handles mount in
such a way as to cover up the old holes on the original 575 top bar.
You center the later hole pattern on the older hole pattern and bolt the
new handles onto the 575 top bar.

You often see the later style top bar with two plastic handles for sale
on eBay. Here's one that is on eBay today as an example.
https://goo.gl/photos/gZD7ZNp8pmAecZMN8
I can take some pictures of the later style handles mounted on a 575 if
any one is interested.
tom jobe...






On 5/9/2017 9:02 AM, 'John Snyder' Kochcal@... [TekScopes] wrote:

Real nice restoration.

Can you tell us more about the handles and what restoration you may have
done?

I have a number of 500's, none of my handles look close to yours.

John

P.S. this link worked better for me no password requested.
<https://goo.gl/photos/gZD7ZNp8pmAecZMN8>

-----Original Message-----
From: TekScopes@... [mailto:TekScopes@...]
Sent: Tuesday, May 09, 2017 5:07 AM
To: TekScopes@...
Subject: [TekScopes] Re: 575 curve tracer on UK eBay

I love my 575. Have a couple in storage in case I ever need a spare.
One of
my hobbies is the restoration of vintage TEK scopes (if it doesn't have
tube's I am not interested). Would like to get a 570 but prices here
in the
USA are very high. Don't see for them for less than $4,000. Here is a link
to photos of one of my restored 575 tracers.

https://goo.gl/photos/gZD7ZNp8pmAecZMN8
https://goo.gl/photos/gZD7ZNp8pmAecZMN8

Cheers,
Steve Ripper


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

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Posted by: steveripper@...
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Yahoo Groups Links



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

Re: Type 503 Oscilloscope Issues

Evan
 

Below is a link to the probes and scopes I have available: https://goo.gl/photos/LEyMqDkCLHuVXpry9 https://goo.gl/photos/LEyMqDkCLHuVXpry9



In short, all of the probes are Tektronix make.


The probe I have with the 503 is P6027 (1X, 1 Mohm, 67 pF). It does not state any specifics on voltages, but from the manual on Checking Power Supply Ripple, this is the correct probe to use for all but the -3000 V (since the scope cannot handle that).


As for the other probes, I have two different 10 X probes (P6053B, 10 Mohm, 9.5 pF, and P6008, 10 Mohm, 7 pF). I also have another 1X probe (P6028, 30 pF). These all have the BNC connector, but I have several UHF to BNC adapters, so they could be used with my 503 as well.


As for the scopes available for use, there are HP 54600B (100 MHz), HP 54502A (400 Mhz), and Agilent Tech MSO6012A (100 Mhz).


- Evan

Re: Need 545B HV Transformer Rewound

pathmd5
 

Thanks so much for your quick reply. I am in no hurry at all. Just let me know how you want to proceed and we'll go from there.


Thanks,

William

Re: Need 545B HV Transformer Rewound

Chuck Harris
 

I do, but right now I am swamped with other work.

If you are not in a hurry, we can work something out.

-Chuck Harris

daleywp@... [TekScopes] wrote:

Hello all,


I just acquired a really nice 545B with the tell-tale signs of the "epoxy
problem." I'm unsure how to contact members directly, but does Chuck Harris still
rewind HV transfomers?


Thanks,


William Daley

Need 545B HV Transformer Rewound

pathmd5
 

Hello all,


I just acquired a really nice 545B with the tell-tale signs of the "epoxy problem." I'm unsure how to contact members directly, but does Chuck Harris still rewind HV transfomers?


Thanks,


William Daley

Re: Type 503 Oscilloscope Issues

ykochcal
 

Evan

What mfg & model number is the 1X probe with the UHF connector?

It may be useable to see the status of the -100V bus if it can handle the DC
voltage in the AC mode. As you would be looking for a small AC voltage on
the -100V the 1X is could be ok. But only if the probe is rated for the DC
value.

John

-----Original Message-----
From: TekScopes@... [mailto:TekScopes@...]
Sent: Tuesday, May 09, 2017 12:57 PM
To: TekScopes@...
Subject: [TekScopes] Re: Type 503 Oscilloscope Issues

So in regards to taking the AC voltage at the -100V bus, all of the DMM's I
have available could not get a reading on the bus (some just gave a value of
0 VAC, while some fluctuated around that). However, my analog meter gave a
steady reading of -195 VAC on the bus (and still ~ 88 VDC). I am not sure if
the VAC is accurate, but it did give an accurate measurement of the wall
outlet VAC, so it is possible.

My primary DMM is a RadioShack 22-166B (autoranging DMM), but I have been
using more recently a Velleman DVM850BL to confirm the readings after
overloading my Beckman 3030 (needs a new low-voltage capacitor).


My analog meter is Triplett Model 630A Volt-Ohm-Mil-Ammmeter. I had
restored this meter a while back, but it is fully functional.


As for the 503's probes, I only have one 1X probe with UHF connector that I
got with the scope, for doing any self-checks. However, there are many
digital oscilloscopes that I could use (just have to reserve one for use
ahead of time). These all use standard BNC connectors, but I am not sure
which probes they have off hand (I can check this evening when the labs are
open for general use).


- Evan






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Posted by: enchanter464@...
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Yahoo Groups Links

TDS 640A

herbgh@...
 

New bee here....Herb.....
I bought a TDS 640A which was advertised "as is,not working" , on EBAy...Indeed...two knobs were broken as was the bezel....but...other than that, it passes all test including the signal path compensation..
155 bucks including shipping...
Pleased , but wondering if there is anyway to increase the acquisition memory? Too, I know that the batteries are on borrowed time... So..here I am...hoping to mine the experience of fellow travelers...Herb in KY..

ps: my scope collection : Tek 422,Tas 465 and Iwatsu 5711..

I bought the latter two from EBAY for parts and not working... The TAS 465 has a bad full wave rectifier in the ps... The Iwatsu gave up from all of my fiddling/troubleshooting and began to work...I wait for it to fail again...but it is being stubborn!!

Re: TR502 A120 Assembly Required.... transistor update

Chuck Harris
 

The only issue I have with your idea is it will
often cause traces to lift off while you are trying
to pump all of that heat into the pcb/substrate.

In this case, with a ceramic substrate, the traces
are probably fused into the ceramic, so it would
probably be ok.

I would still use the hot plate, though. It makes
the amount of time you have to apply full soldering
temperature very short.

-Chuck Harris

edbreya@... [TekScopes] wrote:

Before going through all kinds of hotplate stuff, I'd recommend just trying
soldering it. The biggest factor is that it's now removed from the case. If the
substrate is small, it will heat up anyway, as if it were on a hotplate -
depending on the iron power, of course. You could also try helping it out
thermally - tape it to a sheet of cardboard, which will insulate it somewhat, and
conveniently hold it. The tape has to hold up for a while even when hot, so use
something like masking or fiberglass - not plastic or electrical tape. If the
heating is still insufficient, then look into preheating options.

Ed





------------------------------------ Posted by: edbreya@...
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Yahoo Groups Links

Re: Type 503 Oscilloscope Issues

Michael A. Terrell
 

A lot of meters can not read the AC voltage correctly, when DC is present. An old trick was to use a .1uF, 600VDC (or higher) capacitor in series with the meter to block the DC.

I use a Fluke 8920 20 MHz True RMS series meter that can read the voltage in AC, DC or AC+DC modes.

That Triplett was not designed to read AC+DC simultaneously. It was a common TV shop and electrician's meter, not a lab meter.

-----Original Message-----
From: "aodiversen@... [TekScopes]" <TekScopes@...>
Sent: May 9, 2017 5:00 PM
To: TekScopes@...
Subject: [TekScopes] Re: Type 503 Oscilloscope Issues

Hi Evan,

That 173 VAC is ridiculous, just forget it. (Does the meter really show -173 with a minus sign?). However, the expected VAC is not very low when the cause of all troubles is in the filter or in the load of the -100V supply.

Albert


---In TekScopes@..., <enchanter464@...> wrote :

Yes. Very unusual.

As for the meter's frequency range, the analog meter is supposed to be accurate to up to 1000 c.p.s. (pre-Hz days, but same thing). It does include corrections for up to 20 kHz. However, since AC is still supposed to be very low for the -100 V bus, I doubt even the corrected value of -173 VAC is accurate.


Again, I'll see what probes the scopes have for use, and hopefully can reserve one for use tomorrow.


Evan







Michael A. Terrell

Re: Type 503 Oscilloscope Issues

Albert Otten
 

Hi Evan,

That 173 VAC is ridiculous, just forget it. (Does the meter really show -173 with a minus sign?). However, the expected VAC is not very low when the cause of all troubles is in the filter or in the load of the -100V supply.

Albert


---In TekScopes@..., <enchanter464@...> wrote :

Yes. Very unusual.

As for the meter's frequency range, the analog meter is supposed to be accurate to up to 1000 c.p.s. (pre-Hz days, but same thing). It does include corrections for up to 20 kHz. However, since AC is still supposed to be very low for the -100 V bus, I doubt even the corrected value of -173 VAC is accurate.


Again, I'll see what probes the scopes have for use, and hopefully can reserve one for use tomorrow.


Evan

Re: Type 503 Oscilloscope Issues

Evan
 

Yes. Very unusual.

As for the meter's frequency range, the analog meter is supposed to be accurate to up to 1000 c.p.s. (pre-Hz days, but same thing). It does include corrections for up to 20 kHz. However, since AC is still supposed to be very low for the -100 V bus, I doubt even the corrected value of -173 VAC is accurate.


Again, I'll see what probes the scopes have for use, and hopefully can reserve one for use tomorrow.


Evan

Re: Which probe is better suited for TDS 460A?

 

The P6137 probe is 400MHz and the P6138 probe is 350MHz which makes it
a little odd that the 350MHz P6138 is recommended for the 400MHz
TDS460A.

At high bandwidths when high impedance 1 megohm inputs are used, it is
difficult to maintain good transient response so sometimes Tektronix
produced specific probes for specific oscilloscopes to provide the
correct transient response. This is likely one of those cases.

However in practice, you are unlike to ever see any difference and
actually measuring it would require something like a tunnel diode
calibration source.

On 09 May 2017 19:06:03 +0000, you wrote:

Hi,

I have a question. I am looking at buying Probes for my TDS 460a. From my research on internet, it seems that P6138 could be that probe with 400 MHz frequency bandwidth.

But, I also saw P6137 with the almost same specifications. There are, at times, I have seen large price differences between P6138 and P6137. SO, I want to know whether P6137 and P6138 are interchangeable and whether P6137 will work equaly well with TDS 460A.

With Warm Regards,

Ravi

Re: Type 503 Oscilloscope Issues

Dave Casey
 

"Better late than never, which is what usually happens."

- Some guy at Yahoo

On Tue, May 9, 2017 at 2:56 PM, enchanter464@... [TekScopes] <
TekScopes@...> wrote:



So in regards to taking the AC voltage at the -100V bus, all of the DMM's
I have available could not get a reading on the bus (some just gave a value
of 0 VAC, while some fluctuated around that). However, my analog meter gave
a steady reading of -195 VAC on the bus (and still ~ 88 VDC). I am not sure
if the VAC is accurate, but it did give an accurate measurement of the wall
outlet VAC, so it is possible.

My primary DMM is a RadioShack 22-166B (autoranging DMM), but I have been
using more recently a Velleman DVM850BL to confirm the readings after
overloading my Beckman 3030 (needs a new low-voltage capacitor).


My analog meter is Triplett Model 630A Volt-Ohm-Mil-Ammmeter. I had
restored this meter a while back, but it is fully functional.


As for the 503's probes, I only have one 1X probe with UHF connector that
I got with the scope, for doing any self-checks. However, there are many
digital oscilloscopes that I could use (just have to reserve one for use
ahead of time). These all use standard BNC connectors, but I am not sure
which probes they have off hand (I can check this evening when the labs are
open for general use).


- Evan

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



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

Re: Type 503 Oscilloscope Issues

Evan
 

So in regards to taking the AC voltage at the -100V bus, all of the DMM's I have available could not get a reading on the bus (some just gave a value of 0 VAC, while some fluctuated around that). However, my analog meter gave a steady reading of -195 VAC on the bus (and still ~ 88 VDC). I am not sure if the VAC is accurate, but it did give an accurate measurement of the wall outlet VAC, so it is possible.

My primary DMM is a RadioShack 22-166B (autoranging DMM), but I have been using more recently a Velleman DVM850BL to confirm the readings after overloading my Beckman 3030 (needs a new low-voltage capacitor).


My analog meter is Triplett Model 630A Volt-Ohm-Mil-Ammmeter. I had restored this meter a while back, but it is fully functional.


As for the 503's probes, I only have one 1X probe with UHF connector that I got with the scope, for doing any self-checks. However, there are many digital oscilloscopes that I could use (just have to reserve one for use ahead of time). These all use standard BNC connectors, but I am not sure which probes they have off hand (I can check this evening when the labs are open for general use).


- Evan