Date   
Re: 244x 246x Ebay kit discount code PSWEET20

 

Barry

I have no idea.

Would you mind doing a Buy-it-now, and insert the Ebay discount code PSWEET20 on the line just before the total.

You don't have to complete the Buy.

Just let me know if the code reduces the price.

Thanks

Menahem

Re: 244x 246x Ebay kit discount code PSWEET20

n4buq
 

Hmmm. I just opened that link and there's no discount showing. I wonder if that's country-specific?

Thanks,
Barry - N4BUQ

----- Original Message -----
From: "M Yachad" <@yachadm>
To: TekScopes@groups.io
Sent: Thursday, October 17, 2019 6:01:56 AM
Subject: [TekScopes] 244x 246x Ebay kit discount code PSWEET20

https://www.ebay.com/itm/252865418970

On my listing, I just noticed that Ebay is offering a $25 discount (Kit +
S&H) on my kits.

Valid until 18th October.

I just saw it by chance - Ebay didn't notify me, and I still get paid my full
price.

That means that they are making money hand-over-fist, if they can afford to
offer discounts like that.

So, courtesy of Ebay, if any of you have been holding back on buying my kit,
take advantage of this discount now.

I'll need to see photos of your A1 A2 A3 A5 A9 (and A4 and A14, if
installed), in order to make up the custom kit.

Menahem Yachad
CondorAudio



Re: Yahoo Groups are deleting all files in December

Richard Tyner <shawneesdad@...>
 

I was not sure if any of the old group files might be be on Yahoo or not. Just wanted to let others know just in case

Re: 2465A channel 2 problems

Chuck Harris
 

Hi Gerry,

First, you are not supposed to get a trace, just a pair
of dots, approximately 10 divisions apart.

This is a crucial step, as it affects all future steps.

I would suggest that you always put it in VAR mode, as it
will always give you an adjustable range to hit the mark.

But note: It is most important that the VAR knob be back
in its click before you start the next, and all subsequent,
steps. If you do not do this, you will achieve out-of-range.

If you repeat this step after having done it recently, you
will usually find that the dots are perfectly spaced.

There is no linkage between the 50 ohm annunciator light and
the 50 ohm relay in the preamp. Unless your preamp is broken,
it is in 50 ohm mode.

As a test, when the scope is in normal mode, put the preamps
in 50 ohm mode, and measure them with an ohmmeter. If they
are other than 50 ohm, you have the ever popular burned out
50 ohm load. Unless you are very clever you will be replacing
your preamp, as the resistor is printed on the ceramic substrate.

-Chuck Harris

GerryR wrote:

Another question or two for those in the know: At the beginning of the Cal 02 procedure, it states to connect a 0.5 V standard-amplitude signal to CH 1 and to use CH 2 Position to vertically position the "trace" to within 1 division of the center graticule line, and then to use the CH 1 Position and Volts/DIV VAR controls to obtain a 10-division horizontal signal. I don't get a "trace," only 2 dots. I can position the dots with the controls to put one dot on the first graticule line and the other on the 10th.
Question 1: "Is this "normal," or am I doing something wrong?" I've read and re-read the procedures and can't find any references to this.

Also, at the beginning of the Cal 01 procedure, it states that, "Upon entering Cal 01, the Input Coupling is automatically set to 50 ohm DC ....." This doesn't appear to be true for the other Cal procedures (2,3,4,etc), as I had to install a terminator on my generator to get the actual levels called out in the test procedures (monitored on another scope).
Question 2: "Is this correct, or am I missing something here, as well?

Thanks in advance for any input!

Gerry

Re: 2465A channel 2 problems

GerryR
 

Another question or two for those in the know: At the beginning of the Cal 02 procedure, it states to connect a 0.5 V standard-amplitude signal to CH 1 and to use CH 2 Position to vertically position the "trace" to within 1 division of the center graticule line, and then to use the CH 1 Position and Volts/DIV VAR controls to obtain a 10-division horizontal signal. I don't get a "trace," only 2 dots. I can position the dots with the controls to put one dot on the first graticule line and the other on the 10th.
Question 1: "Is this "normal," or am I doing something wrong?" I've read and re-read the procedures and can't find any references to this.

Also, at the beginning of the Cal 01 procedure, it states that, "Upon entering Cal 01, the Input Coupling is automatically set to 50 ohm DC ....." This doesn't appear to be true for the other Cal procedures (2,3,4,etc), as I had to install a terminator on my generator to get the actual levels called out in the test procedures (monitored on another scope).
Question 2: "Is this correct, or am I missing something here, as well?

Thanks in advance for any input!

Gerry

------ Original Message -----
From: "machineguy59 via Groups.Io" <machineguy59=yahoo.com@groups.io>
To: <TekScopes@groups.io>
Sent: Wednesday, October 16, 2019 6:48 PM
Subject: Re: [TekScopes] 2465A channel 2 problems


How does Channel 2 work when using the scope in the "normal" mode? If it seems about right (just not precisely calibrated) when measuring known voltages then the attenuator is switching.
On Wednesday, October 16, 2019, 03:31:47 PM CDT, GerryR <totalautomation1@...> wrote:

A little history first: Acquired the 'scope recently and everything was working fine. Old battery dated 07-87. Decided to change battery and took all known precautions, but somehow screwed up and requires re-cal. I have attempted re-cal, and went from a "Test 04 Failed 04" to a "Test 04 failed 02" which is a limit failure. Channel 2 "calibrates" up to the 10V input (cal 02), and I get a Limit 130 error, no matter what I try, so I assume that is my problem. In the non-calibrate run mode, the channel 2 input only works up to the 500 mV range (Hi-Impedance input with co-ax) and with the 10X probe, up to 5V. The display range readout works, but in the 1V, 2V and 5V ranges, it appears to stay in the 100 mV, 200 mV and 500 mV ranges, so it appears the attenuator isn't switching properly.

Is there a way to tell whether it is the attenuator, or if the proper outputs are not getting to the drivers for the attenuator relays, or is this still a calibration problem? I have no way to monitor a "word" from the processor at this point. I did try monitoring channel 1 at the drivers and comparing them to channel 2, but found it difficult to get any meaningful data. Any help will be appreciated.
GerryR

244x 246x Ebay kit discount code PSWEET20

 

https://www.ebay.com/itm/252865418970

On my listing, I just noticed that Ebay is offering a $25 discount (Kit + S&H) on my kits.

Valid until 18th October.

I just saw it by chance - Ebay didn't notify me, and I still get paid my full price.

That means that they are making money hand-over-fist, if they can afford to offer discounts like that.

So, courtesy of Ebay, if any of you have been holding back on buying my kit, take advantage of this discount now.

I'll need to see photos of your A1 A2 A3 A5 A9 (and A4 and A14, if installed), in order to make up the custom kit.

Menahem Yachad
CondorAudio

Re: 2465A channel 2 problems

GerryR
 

That's the problem, in the normal mode, the 1, 2 and 5 volt ranges are all off, for example, a 1V signal on the 1V per division scale, displays as if on the 100 mV scale, etc., so I am assuming the attenuator is not switching for those ranges, but don't know if the relays in the attenuator, or the logic telling which tells them to switch that is bad. The digital readout shows 1V on the 1V scale but the display of the wave is as if it is on the 100 mV scale.
Is there a list of digital words for the different scales or a way to tell if the logic is bad?

GerryR

----- Original Message -----
From: "machineguy59 via Groups.Io" <machineguy59=yahoo.com@groups.io>
To: <TekScopes@groups.io>
Sent: Wednesday, October 16, 2019 6:48 PM
Subject: Re: [TekScopes] 2465A channel 2 problems


How does Channel 2 work when using the scope in the "normal" mode? If it seems about right (just not precisely calibrated) when measuring known voltages then the attenuator is switching.
On Wednesday, October 16, 2019, 03:31:47 PM CDT, GerryR <totalautomation1@...> wrote:

A little history first: Acquired the 'scope recently and everything was working fine. Old battery dated 07-87. Decided to change battery and took all known precautions, but somehow screwed up and requires re-cal. I have attempted re-cal, and went from a "Test 04 Failed 04" to a "Test 04 failed 02" which is a limit failure. Channel 2 "calibrates" up to the 10V input (cal 02), and I get a Limit 130 error, no matter what I try, so I assume that is my problem. In the non-calibrate run mode, the channel 2 input only works up to the 500 mV range (Hi-Impedance input with co-ax) and with the 10X probe, up to 5V. The display range readout works, but in the 1V, 2V and 5V ranges, it appears to stay in the 100 mV, 200 mV and 500 mV ranges, so it appears the attenuator isn't switching properly.

Is there a way to tell whether it is the attenuator, or if the proper outputs are not getting to the drivers for the attenuator relays, or is this still a calibration problem? I have no way to monitor a "word" from the processor at this point. I did try monitoring channel 1 at the drivers and comparing them to channel 2, but found it difficult to get any meaningful data. Any help will be appreciated.
GerryR

Re: Yahoo Groups are deleting all files in December

 

It doesn't impact us at all - we moved over to groups.io lock stock and barrel (including all files and pictures) ages ago.

D.

-----Original Message-----
From: TekScopes@groups.io [mailto:TekScopes@groups.io] On Behalf Of Abc Xyz
Sent: 16 October 2019 20:52
To: TekScopes@groups.io
Subject: Re: [TekScopes] Yahoo Groups are deleting all files in December

Is that a Good Thing or a Bad Thing???

On Wed, Oct 16, 2019, 12:06 PM Richard Tyner <shawneesdad@...> wrote:

Yahoo has made the decision to no longer allow users to upload content to
the Yahoo Groups site. Beginning October 21, you won't be able to upload
any more content to the site, and as of December 14 all previously posted
content on the site will be permanently removed. You'll have until that
date to save anything you've uploaded.

73 Richard W4MCD



Re: 2465A channel 2 problems

 

How does Channel 2 work when using the scope in the "normal" mode?  If it seems about right (just not precisely calibrated) when measuring known voltages then the attenuator is switching.

On Wednesday, October 16, 2019, 03:31:47 PM CDT, GerryR <totalautomation1@...> wrote:

A little history first:  Acquired the 'scope recently and everything was working fine. Old battery dated 07-87.  Decided to change battery and took all known precautions, but somehow screwed up and requires re-cal.  I have attempted re-cal, and went from a "Test 04 Failed 04" to a "Test 04 failed 02" which is a limit failure.  Channel 2 "calibrates" up to the 10V input (cal 02), and I get a Limit 130 error, no matter what I try, so I assume that is my problem.  In the non-calibrate run mode, the channel 2 input only works up to the 500 mV range (Hi-Impedance input with co-ax) and with the 10X probe, up to 5V.  The display range readout works, but in the 1V, 2V and 5V ranges, it appears to stay in the 100 mV, 200 mV and 500 mV ranges, so it appears the attenuator isn't switching properly.

Is there a way to tell whether it is the attenuator, or if the proper outputs are not getting to the drivers for the attenuator relays, or is this still a calibration problem?  I have no way to monitor a "word" from the processor at this point.  I did try monitoring channel 1 at the drivers and comparing them to channel 2, but found it difficult to get any meaningful data.  Any help will be appreciated.
GerryR

2465A channel 2 problems

GerryR
 

A little history first: Acquired the 'scope recently and everything was working fine. Old battery dated 07-87. Decided to change battery and took all known precautions, but somehow screwed up and requires re-cal. I have attempted re-cal, and went from a "Test 04 Failed 04" to a "Test 04 failed 02" which is a limit failure. Channel 2 "calibrates" up to the 10V input (cal 02), and I get a Limit 130 error, no matter what I try, so I assume that is my problem. In the non-calibrate run mode, the channel 2 input only works up to the 500 mV range (Hi-Impedance input with co-ax) and with the 10X probe, up to 5V. The display range readout works, but in the 1V, 2V and 5V ranges, it appears to stay in the 100 mV, 200 mV and 500 mV ranges, so it appears the attenuator isn't switching properly.

Is there a way to tell whether it is the attenuator, or if the proper outputs are not getting to the drivers for the attenuator relays, or is this still a calibration problem? I have no way to monitor a "word" from the processor at this point. I did try monitoring channel 1 at the drivers and comparing them to channel 2, but found it difficult to get any meaningful data. Any help will be appreciated.
GerryR

Re: Yahoo Groups are deleting all files in December

Abc Xyz
 

Is that a Good Thing or a Bad Thing???

On Wed, Oct 16, 2019, 12:06 PM Richard Tyner <shawneesdad@...> wrote:

Yahoo has made the decision to no longer allow users to upload content to
the Yahoo Groups site. Beginning October 21, you won't be able to upload
any more content to the site, and as of December 14 all previously posted
content on the site will be permanently removed. You'll have until that
date to save anything you've uploaded.

73 Richard W4MCD



Re: Yahoo Groups are deleting all files in December

Chuck Harris
 

You know, of course, that tekscopes is not on yahoo? Right?

-Chuck Harris

Richard Tyner wrote:

Yahoo has made the decision to no longer allow users to upload content to the Yahoo Groups site. Beginning October 21, you won't be able to upload any more content to the site, and as of December 14 all previously posted content on the site will be permanently removed. You'll have until that date to save anything you've uploaded.

73 Richard W4MCD



Yahoo Groups are deleting all files in December

Richard Tyner <shawneesdad@...>
 

Yahoo has made the decision to no longer allow users to upload content to the Yahoo Groups site. Beginning October 21, you won't be able to upload any more content to the site, and as of December 14 all previously posted content on the site will be permanently removed. You'll have until that date to save anything you've uploaded.

73 Richard W4MCD

Re: Ths730 alternative to p5102 probe

Chuck Harris
 

For audio use, any bnc probe that can handle the voltage
will work just fine. Look at the P6007 and P6009.

-Chuck Harris

Scott Adams via Groups.Io wrote:

Most of my high voltage measurement needs are in the audio frequency range, I like to repair and build vacuum tube stereo amps.



Re: Ths730 alternative to p5102 probe

Scott Adams
 

Most of my high voltage measurement needs are in the audio frequency range, I like to repair and build vacuum tube stereo amps.

Re: Ths730 alternative to p5102 probe

Neil Gruending
 

The industry standard probes for portable oscilloscopes are made by Staubli. They are $60-$80US new and are CAT rated for these types of measurements. Allied/Farnell sells some of the models and you can buy direct if you meet the minimum order ($100US?). Their application people are also very good at matching your requirements to their probes.

Will it be a perfect high fidelity match to the THS370? Probably not but safely measuring high voltages with more than 1MHz of bandwidth can be challenging on a budget. The biggest downside of these safety rated probes are their size compared to the Tek probes although the do have some physically smaller models.

Cheers,
Neil
________________________________
From: TekScopes@groups.io <TekScopes@groups.io> on behalf of Chuck Harris via Groups.Io <cfharris=erols.com@groups.io>
Sent: October 15, 2019 6:52 AM
To: TekScopes@groups.io <TekScopes@groups.io>
Subject: Re: [TekScopes] Ths730 alternative to p5102 probe

The usual rule of thumb is unless your probes are
specifically designed for high voltages, don't subject
your probes to any voltage higher than your scope's
input rating.

So, don't skimp on the probes that are going to protect
you and your scope.

I tend to use P6007's (1.5KV, 25MHz), P6009's (1.5KV, 100MHz),
and P6015's(20KV, 75MHz) for HV applications. The 6007's and
6009's are usually pretty cheap.

Virtually all of the modular, high performance, probes are
rated for less than 400V.

Remember most probes HV rating is for *DC*, or low freq AC,
not RF HV! RF HV is a whole 'nother kettle of fish.

-Chuck Harris


Scott Adams via Groups.Io wrote:
I have a ths730 and want to do measurements on vacuum tube amp circuits that have between 240vdc to 500vdc. I was wondering if there are any recommended alternatives to the p5102 probes, these this sell between $250 to $600 on fleabag.



Right angle extender board, CG50XX...

Chuck Harris
 

Hi,

I am in the middle of a frustrating intermittent problem
with a CG5011, and need a right angle extender board for
lifting the internal pc boards out of their slots.

Anybody have a spare, or know where I can get one?

It is tek part number: 067-0975-00

It is a fairly simple double sided adapter with a 30 pin
0.1" spacing connector.

I've thought about making one, but it would be easier if
I could buy one.

-Chuck Harris

Re: "liquid crystal driver" sighting

Vince Vielhaber
 

It's $56 shipping across the US or I would've.

Vince.

On 10/15/2019 07:29 PM, Craig Sawyers wrote:
At $22 BIN I'm surprised no one in the US has taken a punt just to find out what that plugin does!

The thing that puts me off doing precisely that is $104 shipping to the UK!!!

Craig

This "lot of 3" item on eBay includes a couple of 5A1xN scope plugins and a "liquid crystal driver"
plugin:

https://www.ebay.com/itm/LOT-OF-3-TEKTRONIX-PLUG-IN-5A18N-DUAL-TRACE-AMP-5A15N-AMP-
LIQUID-CRYSTAL-DRIVER/312803078179

The only mentions of a "liquid crystal driver" plugin that I've found are in Dennis T's list of
TM500/TM5000 plugins at davmar.org & TekWiki.

The eBay listing has crude front & back pictures. I might get around to adding the pix to TekWiki.
Feel
free to beat me to it.

Just for curiosity, does anyone here know anything about this mysterious object?


Re: "liquid crystal driver" sighting

Craig Sawyers <c.sawyers@...>
 

At $22 BIN I'm surprised no one in the US has taken a punt just to find out what that plugin does!

The thing that puts me off doing precisely that is $104 shipping to the UK!!!

Craig

This "lot of 3" item on eBay includes a couple of 5A1xN scope plugins and a "liquid crystal driver"
plugin:

https://www.ebay.com/itm/LOT-OF-3-TEKTRONIX-PLUG-IN-5A18N-DUAL-TRACE-AMP-5A15N-AMP-
LIQUID-CRYSTAL-DRIVER/312803078179

The only mentions of a "liquid crystal driver" plugin that I've found are in Dennis T's list of
TM500/TM5000 plugins at davmar.org & TekWiki.

The eBay listing has crude front & back pictures. I might get around to adding the pix to TekWiki.
Feel
free to beat me to it.

Just for curiosity, does anyone here know anything about this mysterious object?

"liquid crystal driver" sighting

p mc
 

This "lot of 3" item on eBay includes a couple of 5A1xN scope plugins and a "liquid crystal driver" plugin:

https://www.ebay.com/itm/LOT-OF-3-TEKTRONIX-PLUG-IN-5A18N-DUAL-TRACE-AMP-5A15N-AMP-LIQUID-CRYSTAL-DRIVER/312803078179

The only mentions of a "liquid crystal driver" plugin that I've found are in Dennis T's list of TM500/TM5000 plugins at davmar.org & TekWiki.

The eBay listing has crude front & back pictures. I might get around to adding the pix to TekWiki. Feel free to beat me to it.

Just for curiosity, does anyone here know anything about this mysterious object?