Date   

Re: 465B Horizontal Sweep help

 

If both deflection plates are stuck at 100V+, the problem is not likely to be the sweep, rather, the horizontal amplifier itself. A sweep problem would leave one plate high and the other low.
--
Bob Haas


Re: 500-series plugin connector (for DIY plugin or extender)

David Kuhn
 

I can see that useful for making an extender cable. I wonder if there ever
were any official extender cables for the 500 series?

On Fri, Aug 13, 2021 at 8:24 AM nicmatfr <nic_o_mat@...> wrote:

I forgot to mention that I'm in France. Shipping outside Europe may be
expensive.

Nicolas
________________________________
De : TekScopes@groups.io <TekScopes@groups.io> de la part de nicmatfr <
nic_o_mat@...>
Envoyé : vendredi 13 août 2021 11:32
À : TekScopes@groups.io <TekScopes@groups.io>
Objet : [TekScopes] 500-series plugin connector (for DIY plugin or
extender)

Hello all
Would anyone be interested in connectors for the 500-series plugins ? I
have found a connector reference and a distributor in the UK but I strongly
suspect they wouldn't sell me 2 pieces only, and the price will certainly
depend on the quantity.

Nicolas











Re: Tek 7623A - Source of 151-0271-00 transistor (A5T4261) or a currently available equivalent.

Miguel Work
 

Did it work?


Re: 500-series plugin connector (for DIY plugin or extender)

Nico F4IAN
 

I forgot to mention that I'm in France. Shipping outside Europe may be expensive.

Nicolas
________________________________
De : TekScopes@groups.io <TekScopes@groups.io> de la part de nicmatfr <nic_o_mat@...>
Envoyé : vendredi 13 août 2021 11:32
À : TekScopes@groups.io <TekScopes@groups.io>
Objet : [TekScopes] 500-series plugin connector (for DIY plugin or extender)

Hello all
Would anyone be interested in connectors for the 500-series plugins ? I have found a connector reference and a distributor in the UK but I strongly suspect they wouldn't sell me 2 pieces only, and the price will certainly depend on the quantity.

Nicolas


Re: 500-series plugin connector (for DIY plugin or extender)

Jonathan Pyle
 

I bought a 013-019 / EP-54 plug-in extender and I found it wasn't as helpful as I thought it would be, so I was thinking of taking it apart and using the connectors to make a cable. However, I'd rather keep that unit whole and buy separate connectors for the cable. So count me in!


500-series plugin connector (for DIY plugin or extender)

Nico F4IAN
 

Hello all
Would anyone be interested in connectors for the 500-series plugins ? I have found a connector reference and a distributor in the UK but I strongly suspect they wouldn't sell me 2 pieces only, and the price will certainly depend on the quantity.

Nicolas


Re: What was the first oscilloscope to have cursors?

ditter2
 

As the reader wrote the original question : “What was the first oscilloscope to have cursors? “ the answers were if the question was “which was the first Tek scope to have cursors?” (include the word Tek)

The first digital scope to include cursors was not from Tek or HP, but rather Nicolet. The engineers at Nicolet really took an “out of the box” approach to thinking about digital scopes whereas both Tek and HP treated the initial offerings of digital scopes like analog – more so for Tek. For example, putting the standard dual/delay time base knob on a digital scope really made no sense when you could control the scope to capture all pre trigger data. Nicolet, not having a long heritage of analog scopes took a different approach. Their first DSO did not have a graticule – only cursors for measurements. Their point was as the graticule was only a crude way to visualize a measurement, why make the user count grid spacings when you can directly measure the time and amplitude of any point of the screen to 3 digit resolution using cursors.
Nicolet’s first DSO (I can’t remember the model number) used the same off the shelf 8 bit ADC as the 468. It was originally designed by TRW for military applications.


575 Bottom panel - questions, sources, etc.

Keith
 

Hi guys and gals,

So the 575 restoration is progressing nicely. I made it through calibration today for the first time! :-) Now I'm looking forward to the moment when I can put the cases on it and start to build Dennis Tilman's VTCT, (yea, Dennis!)

but...

I am lacking the 575 bottom panel. :-/

I see some "500 series" panels on Fleabay, but nothing specific to a 575. And, to figure out interchangeability, I've looked at the various Tek 500 series bottom panel part numbers. So far, the 575 has an unique part number, a couple of them, actually. It is 387-089 for mine, and 386-620 for early serial number units - below #2266.

However, some have suggested that this unique number isn't that significant - perhaps a cosmetic or other minor difference. Some folks feel that lots of 500 series bottoms might physically interchange. Unfortunately, I just have no idea.

So...can anyone comment from a position of certainty? Will (for example) a 535 or 545 or 585 bottom panel fit a 575?

FWIW, this is a working instrument, not a museum piece (not making fun of numbers-correct restos, either. This is just isn't one)

Any wisdom would be much appreciated.

Keith
coolblueglow


Re: Members in Australia

Robert Dixon
 

G'Day All from Brisbane (4306).

I have 7904, 7104, and numerous 7000 plugins (but there is always room for more ...)

Robert Dixon

On 18 Jul 2021, at 07:24, Ken Goodhew <kgoodhew@...> wrote:

another covid free new south welshman from mount warrigal ,wollongong.
VK2TKE





Re: 465B Horizontal Sweep help

 

On Thu, Aug 12, 2021 at 02:12 AM, Ozan wrote:


TP93 should be a clipped sine wave clamped at top by CR4111 (~100V) and
clamped at the bottom by CR4112 (~ 15V to 95V depending on intensity setting).
What do you observe on a scope?
Also, compare the waveshape and voltages at point 91 (TP4217) with the waveform as shown in the diagram. Horizontal settings as under "AC Waveforms" above the image of point 91.

Raymond


Re: 465B Horizontal Sweep help

Ozan
 

On Wed, Aug 11, 2021 at 04:24 PM, Robert Simpson wrote:

The HV meter I am using is a Fluke 27 kit that came with a 6KV HV (80k-6)
probe adapter. According to the Fluke website the probe has 1000:1 75Mohm
resistance for use with a 10Mohm meter. I didn't see a meter resistance
statement but since this probe is one of the options, I would expect the meter
to be 10Mohm
Bob
------------
Hi Bob,
C4010 (47pF) in series with R4112 (390k) replenishes the charge on C4118 (connected to grid) at 50kHz rate. Extra 75M-ohm load should be fine.

TP93 should be a clipped sine wave clamped at top by CR4111 (~100V) and clamped at the bottom by CR4112 (~ 15V to 95V depending on intensity setting). What do you observe on a scope?
Ozan


Re: 465B Horizontal Sweep help

 

On Thu, Aug 12, 2021 at 01:24 AM, Robert Simpson wrote:


The HV meter I am using is a Fluke 27 kit that came with a 6KV HV (80k-6)
probe adapter. According to the Fluke website the probe has 1000:1 75Mohm
resistance for use with a 10Mohm meter. I didn't see a meter resistance
statement but since this probe is one of the options, I would expect the meter
to be 10Mohm
The resistance between the probe tip and the common connection is what counts, apparently 75 MOhm in your setup.

Raymond


Re: 5B12N Op Manual Rework

Liam Perkins <hifi@...>
 

Dennis:
Will you scrub this thread please.
It shouldn't be here in the first place and having provided valid, lowest
cost freight quotes WEEKS ago I'm about to lose my temper.
So, for the third and LAST TIME: this has no business being here and
burning everyone's time

On Wed, Aug 11, 2021 at 4:48 PM Liam Perkins via groups.io <hifi=
telus.net@groups.io> wrote:

On list is not the place.

On Wed, Aug 11, 2021 at 3:52 PM Liam Perkins via groups.io <hifi=
telus.net@groups.io> wrote:

No you didn't, you paid for Canada Post on the 3567A already received in
good order.
You paid $US50.00 against a shipment cost of $US100.00 by Surface Mail or
$US150.00 by Airmail .
On-list is not the place for this in any case

On Wed, Aug 11, 2021 at 1:12 PM cheater cheater <
cheater00social@...
wrote:

Liam,
please get in touch regarding the price of shipping of the manual I
paid for using UPS.

Thanks

On Wed, Aug 11, 2021 at 6:34 AM Liam Perkins <hifi@...> wrote:

I just re-did the somewhat tatty TekWiki Op manual for the 5B12N

https://www.pearl-hifi.com/06_Lit_Archive/15_Mfrs_Publications/35_Tektronix/Tek_5B12N_Timebase_Horiz_Amp.pdf

I don't know how to up' to the 'Wiki so if anyone cares to do so . .
.

Liam

















Re: 465B Horizontal Sweep help

Robert Simpson
 

The HV meter I am using is a Fluke 27 kit that came with a 6KV HV (80k-6) probe adapter. According to the Fluke website the probe has 1000:1 75Mohm resistance for use with a 10Mohm meter. I didn't see a meter resistance statement but since this probe is one of the options, I would expect the meter to be 10Mohm
Bob


Re: 5B12N Op Manual Rework

 

You haven't replied off list. Reply off or on list, I don't care
which, but after you've disappeared for two months, I don't want you
to disappear for another two.

On Thu, Aug 12, 2021 at 12:48 AM Liam Perkins <hifi@...> wrote:

On list is not the place.

On Wed, Aug 11, 2021 at 3:52 PM Liam Perkins via groups.io <hifi=
telus.net@groups.io> wrote:

No you didn't, you paid for Canada Post on the 3567A already received in
good order.
You paid $US50.00 against a shipment cost of $US100.00 by Surface Mail or
$US150.00 by Airmail .
On-list is not the place for this in any case

On Wed, Aug 11, 2021 at 1:12 PM cheater cheater <cheater00social@...
wrote:

Liam,
please get in touch regarding the price of shipping of the manual I
paid for using UPS.

Thanks

On Wed, Aug 11, 2021 at 6:34 AM Liam Perkins <hifi@...> wrote:

I just re-did the somewhat tatty TekWiki Op manual for the 5B12N

https://www.pearl-hifi.com/06_Lit_Archive/15_Mfrs_Publications/35_Tektronix/Tek_5B12N_Timebase_Horiz_Amp.pdf

I don't know how to up' to the 'Wiki so if anyone cares to do so . . .

Liam
















Re: 5B12N Op Manual Rework

Liam Perkins <hifi@...>
 

On list is not the place.

On Wed, Aug 11, 2021 at 3:52 PM Liam Perkins via groups.io <hifi=
telus.net@groups.io> wrote:

No you didn't, you paid for Canada Post on the 3567A already received in
good order.
You paid $US50.00 against a shipment cost of $US100.00 by Surface Mail or
$US150.00 by Airmail .
On-list is not the place for this in any case

On Wed, Aug 11, 2021 at 1:12 PM cheater cheater <cheater00social@...
wrote:

Liam,
please get in touch regarding the price of shipping of the manual I
paid for using UPS.

Thanks

On Wed, Aug 11, 2021 at 6:34 AM Liam Perkins <hifi@...> wrote:

I just re-did the somewhat tatty TekWiki Op manual for the 5B12N

https://www.pearl-hifi.com/06_Lit_Archive/15_Mfrs_Publications/35_Tektronix/Tek_5B12N_Timebase_Horiz_Amp.pdf

I don't know how to up' to the 'Wiki so if anyone cares to do so . . .

Liam













Re: 5B12N Op Manual Rework

 

Liam,
I've asked you a week ago to check with UPS.

You haven't replied about this since. You just kept on rushing me to
pay for the courier you chose. I asked you to look up another one and
you ignored that.

If I can't get in touch with you off list, and you only answer to
on-list emails, what am I supposed to do? You've been ignoring my
emails.

On Wed, Aug 11, 2021 at 11:52 PM Liam Perkins <hifi@...> wrote:

No you didn't, you paid for Canada Post on the 3567A already received in
good order.
You paid $US50.00 against a shipment cost of $US100.00 by Surface Mail or
$US150.00 by Airmail .
On-list is not the place for this in any case

On Wed, Aug 11, 2021 at 1:12 PM cheater cheater <cheater00social@...>
wrote:

Liam,
please get in touch regarding the price of shipping of the manual I
paid for using UPS.

Thanks

On Wed, Aug 11, 2021 at 6:34 AM Liam Perkins <hifi@...> wrote:

I just re-did the somewhat tatty TekWiki Op manual for the 5B12N

https://www.pearl-hifi.com/06_Lit_Archive/15_Mfrs_Publications/35_Tektronix/Tek_5B12N_Timebase_Horiz_Amp.pdf

I don't know how to up' to the 'Wiki so if anyone cares to do so . . .

Liam












Re: 465B Horizontal Sweep help

 

On Wed, Aug 11, 2021 at 11:34 PM, Ozan wrote:


To add to Raymond's comments:
Amount of negative bias depends on the voltage swing at TP93. Higher the swing
at TP93, dimmer is the beam. The swing at TP93 is set by two diode clamps:
CR4111 and CR4112. Checking voltages at the cathode of CR4111 (schematic says
~ 100V expected) and TP91 (schematic says 15 to 95V expected depending on the
intensity setting) can help you pinpoint the issue. It could be as simple as
an accidental setting change of grid bias trimpot.

As a side note in the service manual I am looking at grid bias trimpot is
R4109, and the neon bulbs are DS4124 and DS4125. Most HV probes would have
input resistance much higher than 10M-ohm (the one I have is spec'ed at
1000M-ohm) so loading is probably OK.
Thanks for your comments, Ozan. My component references were for the 465 whereas Robert's is a 465B, sorry about that.

As regards the -2500V: Of course, you're right, hardly any standard DVM (e.g. with 10 MOhm input resistance) would be suitable for measuring above 1 kV or so. I often use a 1:100 probe with 66.67 MOhm input resistance if I want to use a 'scope, or a P6015, with 100 MOhm input impedance at DC. For DC, a Fluke 80K-40 with 1 GOhm does a nice job but is "a bit" big.

Raymond


Re: 5B12N Op Manual Rework

Liam Perkins <hifi@...>
 

No you didn't, you paid for Canada Post on the 3567A already received in
good order.
You paid $US50.00 against a shipment cost of $US100.00 by Surface Mail or
$US150.00 by Airmail .
On-list is not the place for this in any case

On Wed, Aug 11, 2021 at 1:12 PM cheater cheater <cheater00social@...>
wrote:

Liam,
please get in touch regarding the price of shipping of the manual I
paid for using UPS.

Thanks

On Wed, Aug 11, 2021 at 6:34 AM Liam Perkins <hifi@...> wrote:

I just re-did the somewhat tatty TekWiki Op manual for the 5B12N

https://www.pearl-hifi.com/06_Lit_Archive/15_Mfrs_Publications/35_Tektronix/Tek_5B12N_Timebase_Horiz_Amp.pdf

I don't know how to up' to the 'Wiki so if anyone cares to do so . . .

Liam









Re: 465B Horizontal Sweep help

Ozan
 

To add to Raymond's comments:
Amount of negative bias depends on the voltage swing at TP93. Higher the swing at TP93, dimmer is the beam. The swing at TP93 is set by two diode clamps: CR4111 and CR4112. Checking voltages at the cathode of CR4111 (schematic says ~ 100V expected) and TP91 (schematic says 15 to 95V expected depending on the intensity setting) can help you pinpoint the issue. It could be as simple as an accidental setting change of grid bias trimpot.

As a side note in the service manual I am looking at grid bias trimpot is R4109, and the neon bulbs are DS4124 and DS4125. Most HV probes would have input resistance much higher than 10M-ohm (the one I have is spec'ed at 1000M-ohm) so loading is probably OK.

Ozan


On Wed, Aug 11, 2021 at 10:33 PM, Robert Simpson wrote:


Pin 3 on the CRT goes from 2528V to 2512V varying the intensity control. the
manual (page 3-22) indicates a control grid voltage of about 2465 volts.
Looks
like Pin 3 has too many volts and I am wondering if that could cut off the
beam?
Pin 3 is the beam current control grid. Unless it's at least several tens of
volts more negative than the cathode (pin 2), beam current will be very high
under normal conditions and you could expect a very bright spot or trace. The
"grid bias" is used for static adjustment of minimum brightness. Beam cutoff
is at about cathode -70V I guess. Playing with the grid bias setting (R1480)
should quite visibly influence the voltage that you measure and allow setting
full brightness and full blanking. It's easily reset to the right position
later on, so some experimenting won't harm.
OTOH, pin 3 is a very high-impedance point and depending on your meter's input
impedance, the voltage you see will be quite a bit off, IOW too high (less
negative). I'd expect high brightness just connecting your meter, unless its
input resistance is well above 10 - 11 MOhm.
To conclude, I don't think the voltage you see at pin 3 indicates a problem,
on the contrary. Are neon lamps DS1425 and DS1426 off? They should be.

Raymond

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