Date   

Re: Frequency response flatness in conventional sampling (say 7S11/S

 

I think using a sampling oscilloscope for flatness calibration is a
great idea. The sampling heads are both very high bandwidth and have
a very predictable frequency response. The weakest links will be the
SWR match and termination but that applies to any system. You can do
away with cable losses by using a sampling head extender.

If you take the 3db bandwidth numbers I posted earlier and divide by
4, that is the point where the sample head output will be down by 2%.
The second number shown is where they will be down by 1%:

S-1 260 MHz 190 MHz
S-2 1.18 GHz 869 MHz
S-4 3.60 GHz 2.61 GHz
S-6 2.99 GHz 2.17 GHz

I think this is the first time I have had a need to do math involving
a sin(x)/x function.

On Fri, 15 Feb 2013 17:45:49 -0000, "Ed Breya" <edbreya@yahoo.com>
wrote:

Albert, I wouldn't use a sampling scope or even an analog one pushing its BW to calibrate RF generators, except maybe for comparing one against another. A power meter like HP848X heads with HP43X meter is a good way to go, but expensive.

You can also roll your own with modern power level detector ICs - they can also be used directly in the generator leveling loops to improve performance. I'm familiar with some from Analog Devices, but I'm sure the usual companies have plenty to choose from too. These are very common ICs used in huge quantities for all the wireless gear out there.

Here's a place to start looking:

http://www.analog.com/en/rfif-components/detectors/products/index.html#RMS_Detectors

It would take quite a bit of investigation and experimenting, but the trick is mostly to get the desired broadband flatness in the coupling of the signal to the IC, and of course, the right dynamic range. Logarithmic and linear responses are available. With linear, you can expand the measurement for better resolution over a small range for calibration purposes, but have less overall dynamic range.

These devices usually measure true RMS voltage over the entire bandwidth, so if your waves have lots of distortion, the harmonic power will be counted too, up to the BW, then diminished. This also could give a quite different result than looking at the p-p envelope even on a perfectly flat scope - another reason to not use a scope, unless p-p voltage is what's wanted.

Ed


Re: Plastic binders for TEK Manuals By hand

Robert Simpson
 

I Love it! Simple, works, cheap, do it at home = functionally elegant.
Thanks,
Bob

--- In TekScopes@yahoogroups.com, Artekmedia <manuals@...> wrote:

After several requests I have created a short step by step process for
reinstalling the plastic comb bindings on a Tek manual by hand. No
expensive machine required. A 2" manual can be done in about 2 minutes
or less a smaller manual in less than a minute. The only item to
purchase is a letter opener that fits in the slots . You can use a tie
wrap for this step too but the metal opener works better

The photos of the step by step are in the photos area in a folder "Comb
Binding by Hand"

I also have this in a PDF ( what else :-) ) , email me for a copy

Dave
ArtekManuals.com



On 2/12/2013 11:46 AM, Artekmedia wrote:
When I get time ( yeah right !) I will do a photo tutorial of how to
do this without the machine small manual can be done in less than 1
minute by hand a large manual takes 2 minutes worst case

Dave
ArtekManuals
--
Dave Henderson
Manuals@...
www.Artekmanuals.com
PO Box 175
Welch,MN 55089
651-269-4265


Plastic binders for TEK Manuals By hand

Artekmedia <manuals@...>
 

After several requests I have created a short step by step process for reinstalling the plastic comb bindings on a Tek manual by hand. No expensive machine required. A 2" manual can be done in about 2 minutes or less a smaller manual in less than a  minute. The only item to purchase is a letter opener that fits in the slots . You can use a tie wrap for this step too but the metal opener works better

The photos of the step by step are in the photos area in a folder "Comb Binding by Hand"

I also have this in a PDF ( what else :-) ) , email me for a copy

Dave
ArtekManuals.com



On 2/12/2013 11:46 AM, Artekmedia wrote:
When I get time ( yeah right !) I will do a photo tutorial of how to do this without the machine small manual can be done in less than 1 minute by hand a large manual takes 2 minutes worst case

Dave
ArtekManuals

-- 
Dave Henderson
Manuals@...
www.Artekmanuals.com
PO Box 175
Welch,MN 55089
651-269-4265


Re: Tektronix A6901 ground isolation monitor

Dave Wise
 

Thanks, Steve, your description cured me of any desire to acquire an A6901 :)

Dave Wise

-----Original Message-----
From: TekScopes@yahoogroups.com [mailto:TekScopes@yahoogroups.com] On Behalf Of Steve
Sent: Wednesday, February 13, 2013 4:14 PM
To: TekScopes@yahoogroups.com
Subject: [TekScopes] Re: Tektronix A6901 ground isolation monitor

--- In TekScopes@yahoogroups.com, "fred" wrote:

I have one, can anybody tell more about it. I can not find a manual and the info I do find is confusing.

I know it should be used between scope and mains but I read
- it floats the scope and switches off the power if there is > 40V ground difference
- it grounds the scope but over 40V it beeps as warning and then floats the scope.

I use a huge variac and isolation tranfsormer to connect the instruments I'm repairing. I wanted to use this instead in some cases so it is still save but I know when there is a problem ( for instance leaking netfilter caps or transformer)
And in other cases/experiments protect for instance a signal generator or scope . So it's original use.

Fred PA4TIM
In the fault trip mode, it does not float the scope - it grounds it!!!!

I have never figured this thing out. and I can see as a real source of danger if used incorrectly.


Leader counter (project) FS

bonddaleena@...
 

Hi to all.
One of the many things I collect are frequency counters (don't ask me why)....sigh......
In particular, I really like Leader test equipment and have quite a bit. I have one Model 824S counter (520 MHz) that has a problem.
It is not dead, and tries to count, but has a problem somewhere in the display driver(s). It is complete and in pretty nice shape except for a crack in the plastic around the BNC connector, which I have fixed.

Actual shipping from 32094. Make me an offer or I'll just keep it for parts.

I also have 20+ 100% functional scopes (these are 'spares'), which I prefer not to ship. Got a huge collection of everything I need to thin out.

Pix upon request.

n4ue@...

or

bonddaleena@...

tnx
ron
N4UE


Re: Re; TDS520D IC identification.

马林
 

I10412 is DAC with 16way outputs.Control attenuator,preamp,trigger comparator.

--- In TekScopes@yahoogroups.com, "Clive Ainsworth" <crainsworth@...> wrote:

I am currently trying to repair my lab TDS520D and would appreciate help in identifying one of the IC's on the acquisition board.

There are 3 IMP I10412-01's towards the front of the board. Does anyone have data on this device. I have found several sources of supply, but understand IMP went bankrupt and have spent a couple of hours searching for details of the device without success.

Any help would be appreciated.

Clive A.


WTB: 7CT1N Curve Tracer Plugin

chrismh_somenumber <hogancm@...>
 

Anyone have one for sale?

Please contact me off list.

Thanks,
Chris


Re: Re; TDS520D IC identification.

 

Hi Clive,

These are also in TDS700 series scopes. I suspect that they are used to control the attenuators, but that's just a guess.

Jay

--- In TekScopes@yahoogroups.com, "Clive Ainsworth" <crainsworth@...> wrote:

I am currently trying to repair my lab TDS520D and would appreciate help in identifying one of the IC's on the acquisition board.

There are 3 IMP I10412-01's towards the front of the board. Does anyone have data on this device. I have found several sources of supply, but understand IMP went bankrupt and have spent a couple of hours searching for details of the device without success.

Any help would be appreciated.

Clive A.


Re: Frequency response flatness in conventional sampling (say 7S11/S

Ed Breya
 

Albert, I wouldn't use a sampling scope or even an analog one pushing its BW to calibrate RF generators, except maybe for comparing one against another. A power meter like HP848X heads with HP43X meter is a good way to go, but expensive.

You can also roll your own with modern power level detector ICs - they can also be used directly in the generator leveling loops to improve performance. I'm familiar with some from Analog Devices, but I'm sure the usual companies have plenty to choose from too. These are very common ICs used in huge quantities for all the wireless gear out there.

Here's a place to start looking:

http://www.analog.com/en/rfif-components/detectors/products/index.html#RMS_Detectors

It would take quite a bit of investigation and experimenting, but the trick is mostly to get the desired broadband flatness in the coupling of the signal to the IC, and of course, the right dynamic range. Logarithmic and linear responses are available. With linear, you can expand the measurement for better resolution over a small range for calibration purposes, but have less overall dynamic range.

These devices usually measure true RMS voltage over the entire bandwidth, so if your waves have lots of distortion, the harmonic power will be counted too, up to the BW, then diminished. This also could give a quite different result than looking at the p-p envelope even on a perfectly flat scope - another reason to not use a scope, unless p-p voltage is what's wanted.

Ed

--- In TekScopes@yahoogroups.com, "David C. Partridge" <david.partridge@...> wrote:

Well yes it might be, but if you don't have one ...

Also for the uninitiated (i.e. me) how accurate are power meters?

Dave

________________________________

From: TekScopes@yahoogroups.com [mailto:TekScopes@yahoogroups.com] On Behalf Of HankC
Sent: 15 February 2013 14:50
To: TekScopes@yahoogroups.com
Subject: [TekScopes] Re: Frequency response flatness in conventional sampling (say 7S11/S


If you just want to measure amplitude, wouldn't a power meter be easier ?


Re: Frequency response flatness in conventional sampling (say 7S11/S

 

Well yes it might be, but if you don't have one ...

Also for the uninitiated (i.e. me) how accurate are power meters?

Dave

________________________________

From: TekScopes@yahoogroups.com [mailto:TekScopes@yahoogroups.com] On Behalf Of HankC
Sent: 15 February 2013 14:50
To: TekScopes@yahoogroups.com
Subject: [TekScopes] Re: Frequency response flatness in conventional sampling (say 7S11/S


If you just want to measure amplitude, wouldn't a power meter be easier ?


Re: Frequency response flatness in conventional sampling (say 7S11/S

 

If you just want to measure amplitude, wouldn't a power meter be easier ?


OT - Tektronix 067-1039-00 Pattern Generator

Dave Daniel
 

All,

I've posted this question to the tek500 group, but I thought I might be allowed to ask the question here as well.

Does anyone know anything about something listed as a Tektronix 067-1039-00 Pattern Generator? It is listed on eBay, item # 221189634326?

Please reply off-list to me (unless there is general interest from the group).

Thanks,
Dave


Re: Off topic B&K Precision 1801 frequency counter

tikitoteam
 

Hi again,i want to thank you David for your help,the ic 74ls90 came home yesterday and i got up early to work on it,i decide to put a socket in case it need to be changed again on the future and viola the counter is working as new...i really appreciate the help of all of you guys, now i have another piece of equipment on my collection....thanks so much

It,s a picture of the counter measure a 1khz signal....


On Wed, Feb 6, 2013 at 10:59 AM, David <davidwhess@...> wrote:
 

On Wed, 06 Feb 2013 05:55:30 -0500, Mark Wendt
mark.wendt@...> wrote:

>On 02/06/2013 03:11 AM, David wrote:
>> On Wed, 6 Feb 2013 01:33:43 -0500, Chris G tikitoteam@...>
>> wrote:
>>
>>> Well,what a nice lesson of troubleshooting i'm getting with your help
>>> David,your are amazing man...
>> I got a lot of practice last year rebuilding frequency counters. The
>> 7D15 and DC505 I worked on had some interesting problems.
>
>Along with all the fun we had with my SG503. ;-)

I forgot about that. Diagnosing your SG503 was fun. My SG503 had an
intermittent open around one IC which has gone away although I have
not changed the sockets yet.

I suppose technically I also repaired the frequency counter in my
PG506 although it is used to measure voltage. That one had a bad 7475
quad latch and I was able to successfully diagnose the problem just by
watching its behavior without any test equipment.



Re; TDS520D IC identification.

ainsworthcr
 

I am currently trying to repair my lab TDS520D and would appreciate help in identifying one of the IC's on the acquisition board.

There are 3 IMP I10412-01's towards the front of the board. Does anyone have data on this device. I have found several sources of supply, but understand IMP went bankrupt and have spent a couple of hours searching for details of the device without success.

Any help would be appreciated.

Clive A.


Re: Frequency response flatness in conventional sampling (say 7S11/S-2)

Albert <aodiversen@...>
 

Thanks for the offer Raymond. I'll contact you off list.
Albert


2465B what should the Inverter voltage be with a primary test load be?

ykochcal
 

Can any one tell me what voltage you have seen with the "primary test load"?

I have been working on a 2465B that had a burned smell on power on.

(message 87960 and 87620)

I think the primary problem was that the -8V cap C1102 leaked and the board under it turned conductive and fried. I have drilled a hole in that spot now.

Something else is not working

I removed the all the caps on the secondary side of T1060 except for the +5VD and I have two, Two ohm resistors connected for a +5v load.

The inverter runs with a low input voltage (less then 90VAC) but cuts out as the input voltage increases.

To try to track down the problem I made a Primary test load and connected it.

I get about a 120 VDC average across the test load but the voltage swing is more like +/- 10 V to 15 V with a triangle wave with the positive tips flattened.

The Inverter trouble shooting flow chats say that their should be 120V with a 1V P-P triangle wave.

The only thing I can see is that R1071 has been hot. Other then the larger triangle wave I don't yet see what the problem is.


Not making any progress I went to another working 2465B with power voltages that check ok and removed the power supply, I had to change the X2 line capacitors anyway.

I placed it in the original bad scope and it worked.

To compare with the non-working supply I took it back out on the bench and connected the primary test load and get the same looking wave which has a much higher P-P voltage then listed in the manual. 120V with about 20V peak triangle wave (smaller p-p as the load is increase by 75W but still at 10-15 volts p-p)



Can any one tell me what voltage you have seen with the primary test load?

Should it a 1-2V triangle or 20V triangle wave?

If it should be 1-2V what would make it higher?

Thanks
John Snyder


Re: Strange AEROVOX cap on my 564

Don Black <donald_black@...>
 

And sometimes become a voltage source i.e. they become a battery. That can really throw out equipments operation. You can measure the voltage with a voltmeter, it's steady, not just a charge that will leak away.

Don Black.

On 15-Feb-13 12:57 PM, Bob Albert wrote:
 

When insulating materials get old, there is no telling what might happen to their electrical characteristics.  On capacitors like that, the ESR tends to increase with age.  They sometimes leak and sometimes lose capacitance and sometimes short.  You never know.

Bob

--- On Thu, 2/14/13, Max Mazza wrote:

From: Max Mazza
Subject: [TekScopes] Re: Strange AEROVOX cap on my 564
To: TekScopes@...
Date: Thursday, February 14, 2013, 5:30 PM

 

Very interesting. I didn't know these things...
But may these caps become so leaky?
I'm still surprised. I've just finished to recalibrate the CRT storage section of my 564, and still I'm mumbling around these strange capacitors.
Should pay more attention in the future, when I see these types of?

Max

--- In TekScopes@..., Bob Albert wrote:
>
> That is not electrolytic.  The band around one end indicates outside foil.
>
> These are wrapped with alternate layers of conducting foil and insulation.  When it's finished being rolled, one lead is of course on the outside.  It's shown on the case to help when you want to pick one lead to ground, for hum pickup considerations.  Usually it doesn't matter.
>
> Bob



Re: TDS 744A Power Supply Issue - Any Ideas?

Andy
 

Yes, you can cause a LOT of damage by jumping the fuse.

--- In TekScopes@yahoogroups.com, Chin Siang Lim wrote:

Might want to put a 60 watts bulb in series with the mains input to the
744.
Keep going, you can surely repair this.
Cslim


Re: Strange AEROVOX cap on my 564

bonddaleena@...
 

I just love old capacitors. What is interesting (at least to me) is that .01 / 600 VDC cap when put on a decent bridge to check VALUE, it will probably measure right at .01 uf. When tested with a 'leakage' tester, it will fail miserably.
I have replaced thousands of caps in my ham radios and test equipment. The 'leakage' tester test the cap at it's rated voltage. A 'bridge' will typically use a 9 V battery. After many years, I have come to the conclusion for adquately testing caps, you need 3 pieces of TE:
1. A HV leakage tester that tests caps at their rated voltage. (paper, mica, etc)
2. a bridge type of instrument for checking value and for identifying caps (great for measuring variable caps, too)
3. an ESR tester for electrolytics

regards,

ron
N4UE



-----Original Message-----
From: Bob Albert
To: TekScopes
Sent: Thu, Feb 14, 2013 8:57 pm
Subject: Re: [TekScopes] Re: Strange AEROVOX cap on my 564

 
When insulating materials get old, there is no telling what might happen to their electrical characteristics.  On capacitors like that, the ESR tends to increase with age.  They sometimes leak and sometimes lose capacitance and sometimes short.  You never know.

Bob

--- On Thu, 2/14/13, Max Mazza <mmazza@...> wrote:

From: Max Mazza <mmazza@...>
Subject: [TekScopes] Re: Strange AEROVOX cap on my 564
To: TekScopes@...
Date: Thursday, February 14, 2013, 5:30 PM

 
Very interesting. I didn't know these things...
But may these caps become so leaky?
I'm still surprised. I've just finished to recalibrate the CRT storage section of my 564, and still I'm mumbling around these strange capacitors.
Should pay more attention in the future, when I see these types of?

Max

--- In TekScopes@..., Bob Albert wrote:
>
> That is not electrolytic.  The band around one end indicates outside foil.
>
> These are wrapped with alternate layers of conducting foil and insulation.  When it's finished being rolled, one lead is of course on the outside.  It's shown on the case to help when you want to pick one lead to ground, for hum pickup considerations.  Usually it doesn't matter.
>
> Bob


Re: Strange AEROVOX cap on my 564

Bob Albert
 

When insulating materials get old, there is no telling what might happen to their electrical characteristics.  On capacitors like that, the ESR tends to increase with age.  They sometimes leak and sometimes lose capacitance and sometimes short.  You never know.

Bob


--- On Thu, 2/14/13, Max Mazza wrote:

From: Max Mazza
Subject: [TekScopes] Re: Strange AEROVOX cap on my 564
To: TekScopes@...
Date: Thursday, February 14, 2013, 5:30 PM

 

Very interesting. I didn't know these things...
But may these caps become so leaky?
I'm still surprised. I've just finished to recalibrate the CRT storage section of my 564, and still I'm mumbling around these strange capacitors.
Should pay more attention in the future, when I see these types of?

Max

--- In TekScopes@..., Bob Albert wrote:
>
> That is not electrolytic.  The band around one end indicates outside foil.
>
> These are wrapped with alternate layers of conducting foil and insulation.  When it's finished being rolled, one lead is of course on the outside.  It's shown on the case to help when you want to pick one lead to ground, for hum pickup considerations.  Usually it doesn't matter.
>
> Bob

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