开云体育

Have you tried using a external trigger input?
Mike

Hi Steve,
How about starting your search where the A sweep waveform originates on
page 3-10 in the "Theory of Operation" section.
It clearly describes how the waveform is generated.
tom jobe...

Hi,

I use this Hameg feature since 1981. The construction is rather easy, you need an independent winding on the 50(60) Hz power transformer and 2 resistors. One resistor will exhibit voltage and the other will exhibit current. This way, you will obtain a U-I-diagram with 7V RMS and 10 mA RMS. I have measured tunnel diodes this way without destroying them. B&K was a trade name for some scopes in the US.

Regards, Jochen DH6FAZ

Am 17.12.2014 04:49, schrieb David davidwhess@... [TekScopes]:

Hi Michael,

Yes, I have checked LINE (no trace) and EXTERNAL trigger and I get no trace but if it's a clue, when I connect a signal to the external trigger port, I DO get the trigger light on .... but no sweep. That makes me think the trigger is working but not driving the sweep circuitry. Any more thoughts???

Thanks!

Steve

any place I can find. my test bench is in the laundry nook. and that is our single wide in town. our double-wide at the ranch has a 14x12 bedroom that is all mine! my wife plans on working in town another year or so and then it is back to our country home with armadillos and coyotes for neighbors.

Jerry Massengale

As with any piece of equipment it has its nitch the huntron tracker will?evolve I have used and demonstrated the tracker in large?pc board shops they love it. Most of the people who use it are not techs or engineers they are in production. Its a fairly?inexpensive piece of equipment and rather small.Being tied to a AC cord is better than a dead battery. Being extremely limited in their capability is exactly what the production manager wants, find the short.?
? From: "'Dennis Tillman' dennis@... [TekScopes]" <TekScopes@...>
To: TekScopes@...
Sent: Tuesday, December 16, 2014 7:33 PM
Subject: [TekScopes] Huntron Tracker's days are numbered (was: 7704A -just a quickie)

? The underlying idea behind the Huntron Tracker is an old one and there are
many circuit variations on the internet if anyone is interesting in building
one or adapting their scope to do the same thing. All that is needed is a
rudimentary scope with XY capability. Any one of us could build one in an
evening with parts on hand.

I think Huntron's days are limited. Their products have many drawbacks that
makes them ripe for overnight obsolescence:

* They are comparatively large

* They are among the last to use CRT technology

* They are tied to a power cord

* They are extremely limited in their capability

* They are hardware based.

With the advent of chips like the Arduino and cheap 256x256 full color LCD
displays I don't think it will be long before someone in China comes up with
a "Tracer". The solid state Tracer would:

* Be hand held

* Sell for ~$25

* Be software based

* Be battery powered

* Use a full-color touch-screen display

Since the software is so easy to change I would not be surprised if over
time additional functionality was added such as the ability to measure ACV,
DCV, ACA, DCA, R, L, and C. With small changes to the hardware it would not
be hard to add a true curve tracer capability to it as well.

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

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Double wide, half of one to live in and the other one and a half for scopes? That sounds fair.


Peter

On Dec 17, 2014, at 2:28 PM, Daniel Koller kaboomdk@... [TekScopes] <TekScopes@...> wrote:

Wait a minute. you have a mobile home? where on earth do you keep all your scopes?
Dan


On Wednesday, December 17, 2014 1:46 PM, "jerry massengale j_massengale@... [TekScopes]" <TekScopes@...> wrote:




Hi,

I may have found a decent coax tester. I wanted something to check out the TV cables in my double wide mobile home. The Klein VDV Distance Meter does a mice job of that. It comes ready for several cables including Cat6, Cat5E, Cat3,RG-59,RG-11,RG-6. It has a user mode that allows you enter other cables capacitance/foot or meter vales. I entered 25pf/ft for rg-58 and 30.5pf/ft for RG-174 and got very accurate readings. I see it as a poor boys TDR. Total cost was $39+$10.72 shipping.

Jerry Massengale



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

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

Wait a minute. ?you have a mobile home? ?where on earth do you keep all your scopes?
? Dan

Thanks, guys!.
Micheal, there are some good exercises in there. I'll play with some
transformers on my Philips PM5132 and figure out the impedance.
(I tend to 'binge' on this stuff in January and the middle of the summer
when the freelance music scene is dead around here. That means every time I
get back at it, it feels like I'm starting all over. It's just like music.
With no regular drill, stuff just doesn't stick very well.)

Mark, I keep my old Olympus E-500 close by. It really is time to find a
macro lens for it. That borescope is enticing. Waterproof too! Add a couple
of LEDs and it would also be good for the kitchen drain that gives trouble
from time to time.

Dennis, I saved all of that. A few small projects like that will help to
keep my head straight between my 'binges'.

HOLY MACKEREL!!!!! The caps I ordered from Mouser at 10:00 last night just
arrived here (at noon). That's pretty seductive.

Keith



On Wed, Dec 17, 2014 at 8:45 AM, 'Michael A. Terrell'
mike.terrell@... [TekScopes] <TekScopes@...> wrote:

Mark Wendt mark.wendt.ctr@... [TekScopes] wrote:

On 12/16/2014 09:18 PM, 'Michael A. Terrell' mike.terrell@...
[TekScopes] wrote:

My troubleshooting is to always inspect & test the power supply,
then break the problem down into blocks. A quick signal tracing narrows
down the problem stage, then you look for defective components. Today,
ESR testing is a must on any modern equipment. In the past, I could
repair some common items in two minutes with nothing more than a VTVM,
1/4" nut driver and a soldering iron.

I later worked at Microdyne (Now L3-Com), troubleshooting new VXI
based cards for an $80,000 telemetry system that we manufactured. That
required a lot of other techniques, including locating hairline shorts,
and shorted components without damaging a board with over $8000 worth of
components. I used a HP 651, and a transformer to give a very low
impedance 1 KHz sinewave, and followed the signal along traces with a
Fluke 8920 True RMS Voltmeter. (The transformer was from a junked
Commodore 1541 floppy drive power supply and they could be had for free
at the time.) The 10:1 turns ratio took the output impedance of the 651B
down from 50 Ohms to .5 ohms. By using a 100 mV output, the level was
low enough to not turn on any semiconductors, or protection diodes.
Follow the trace while watching the voltage drops. The steps are large,
until you reach the short. Once they level off, go back one point and
start looking. That saved me hours of time on the bench. When I combined
all the little tricks I knew, It made me more than twice as productive
as anyone else in the department. :)

I had a Tek 2465B scope, and about 30 other pieces of test
equipment, with many connected to the in house GPS derived 10 MHz
standard. Each repair is different, but start with the basics before
deciding what you need to do next. Also, it doesn't hurt to keep a
notebook and a good digital camera with Macro capability on the
bench(es) to make notes and keep a photo record of how something was
assembled.

The camera on the workbench is a must. It's saved my bacon more than a
few times, especially with complicated cabling. I now have one
dedicated strictly to the workbench so it's always there when I need it.

Mark

I recently bought a cheap Borescope camera to be able to look under
harnesses, and boards or other places. It can be used to read part
numbers, if you have steady hands. :)



---
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------------------------------------

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Yahoo Groups Links

--
Keith Smith - KeithSmith.ca_Freelance Guitarist & Location Recording Service
<>

Hi,

I may have found a decent coax tester. I wanted something to check out the TV cables in my double wide mobile home. The Klein VDV Distance Meter does a mice job of that. It comes ready for several cables including Cat6, Cat5E, Cat3,RG-59,RG-11,RG-6. It has a user mode that allows you enter other cables capacitance/foot or meter vales. I entered 25pf/ft for rg-58 and 30.5pf/ft for RG-174 and got very accurate readings. I see it as a poor boys TDR. Total cost was $39+$10.72 shipping.

Jerry Massengale

<Any curve tracer (even the venerable 575) can do everything a Huntron
Tracker can do.

In fact a Huntron is just a simple one parameter curve tracer.

The thing that surprises me all the time is how many people think curve
tracers are only for measuring semiconductors.

Curve tracers are very versatile. What they can do is limited only by the
ingenuity of the operator.

Dennis Tillman W7PF >


I'm with you on that Dennis!
Never had a Huntron but had a similar function NLS component comparator.
It would automatically toggle between two inputs to compare the x-y waveform.
My first curve tracer was an Eico which needed an X-Y scope and worked fairly well.
Then I came across a Heath IT-1121 which works real well into one of the Tek X-Y
Scopes.
Found a good deal on a 577 in need of a ps recapping several years ago for the
more serious work and also have a 7CT1N for quick low level audio transistor and
zener diode checking and matching.
With the ongoing problem of clone/fake semiconductors these are good tools to have.
Bill, KB3DKS

Mark Wendt mark.wendt.ctr@... [TekScopes] wrote:

On 12/16/2014 09:18 PM, 'Michael A. Terrell' mike.terrell@...
[TekScopes] wrote:

My troubleshooting is to always inspect & test the power supply,
then break the problem down into blocks. A quick signal tracing narrows
down the problem stage, then you look for defective components. Today,
ESR testing is a must on any modern equipment. In the past, I could
repair some common items in two minutes with nothing more than a VTVM,
1/4" nut driver and a soldering iron.

I later worked at Microdyne (Now L3-Com), troubleshooting new VXI
based cards for an $80,000 telemetry system that we manufactured. That
required a lot of other techniques, including locating hairline shorts,
and shorted components without damaging a board with over $8000 worth of
components. I used a HP 651, and a transformer to give a very low
impedance 1 KHz sinewave, and followed the signal along traces with a
Fluke 8920 True RMS Voltmeter. (The transformer was from a junked
Commodore 1541 floppy drive power supply and they could be had for free
at the time.) The 10:1 turns ratio took the output impedance of the 651B
down from 50 Ohms to .5 ohms. By using a 100 mV output, the level was
low enough to not turn on any semiconductors, or protection diodes.
Follow the trace while watching the voltage drops. The steps are large,
until you reach the short. Once they level off, go back one point and
start looking. That saved me hours of time on the bench. When I combined
all the little tricks I knew, It made me more than twice as productive
as anyone else in the department. :)

I had a Tek 2465B scope, and about 30 other pieces of test
equipment, with many connected to the in house GPS derived 10 MHz
standard. Each repair is different, but start with the basics before
deciding what you need to do next. Also, it doesn't hurt to keep a
notebook and a good digital camera with Macro capability on the
bench(es) to make notes and keep a photo record of how something was
assembled.

The camera on the workbench is a must. It's saved my bacon more than a
few times, especially with complicated cabling. I now have one
dedicated strictly to the workbench so it's always there when I need it.

Mark

I recently bought a cheap Borescope camera to be able to look under harnesses, and boards or other places. It can be used to read part numbers, if you have steady hands. :)

On 12/17/2014 8:59 AM, n4bos@... [TekScopes] wrote:

Hi Michael,

Yup, as I suspected, a signal (1Khz sine) into the X input gives a
full width trace across the screen and into the Y input gives a full
width vertical trace so it looks like both the horizontal and vertical
amps are working fine. Any suggestions where to look for the "lost
trigger". I have looked all over the Miller and Shmidt trigger
circuits and find no voltages out of line but no sawtooth anywhere. I
know I'm overlooking something but (obviously) I don't see it.

Thanks!

Steve

FWIW One of the Tek scopes in my ToBeFixed line really can't do anything
useful and yet it does not have any! electrical problems.
It's just a case of ( front panel ) switches that don't..... switch.
Have you checked external trigger and line trigger functions?

'Dennis Tillman' dennis@... [TekScopes] wrote:

Any curve tracer (even the venerable 575) can do everything a Huntron
Tracker can do.

In fact a Huntron is just a simple one parameter curve tracer.

The thing that surprises me all the time is how many people think curve
tracers are only for measuring semiconductors.

Curve tracers are very versatile. What they can do is limited only by the
ingenuity of the operator.

Dennis Tillman W7PF

Most have never used anything better than the Huntron, or other low grade device. They are shown the one use, and that's it. I had to show another tech how to troubleshoot the HV power supply in the Microdyne spectrum displays. He couldn't figure out how to do it without the output transistors connected to the HV transformer. A simple test fixture to provide suitable resistor dummy loads cured that. :)

Very few people ever learn the full capacity of everything on their workbench. :(

Hi Michael,

Yup, as I suspected, a signal (1Khz sine) into the X input gives a full width trace across the screen and into the Y input gives a full width vertical trace so it looks like both the horizontal and vertical amps are working fine. Any suggestions where to look for the "lost trigger". I have looked all over the Miller and Shmidt trigger circuits and find no voltages out of line but no sawtooth anywhere. I know I'm overlooking something but (obviously) I don't see it.

Thanks!

Steve

On 12/16/2014 09:18 PM, 'Michael A. Terrell' mike.terrell@... [TekScopes] wrote:

My troubleshooting is to always inspect & test the power supply,
then break the problem down into blocks. A quick signal tracing narrows
down the problem stage, then you look for defective components. Today,
ESR testing is a must on any modern equipment. In the past, I could
repair some common items in two minutes with nothing more than a VTVM,
1/4" nut driver and a soldering iron.

I later worked at Microdyne (Now L3-Com), troubleshooting new VXI
based cards for an $80,000 telemetry system that we manufactured. That
required a lot of other techniques, including locating hairline shorts,
and shorted components without damaging a board with over $8000 worth of
components. I used a HP 651, and a transformer to give a very low
impedance 1 KHz sinewave, and followed the signal along traces with a
Fluke 8920 True RMS Voltmeter. (The transformer was from a junked
Commodore 1541 floppy drive power supply and they could be had for free
at the time.) The 10:1 turns ratio took the output impedance of the 651B
down from 50 Ohms to .5 ohms. By using a 100 mV output, the level was
low enough to not turn on any semiconductors, or protection diodes.
Follow the trace while watching the voltage drops. The steps are large,
until you reach the short. Once they level off, go back one point and
start looking. That saved me hours of time on the bench. When I combined
all the little tricks I knew, It made me more than twice as productive
as anyone else in the department. :)

I had a Tek 2465B scope, and about 30 other pieces of test
equipment, with many connected to the in house GPS derived 10 MHz
standard. Each repair is different, but start with the basics before
deciding what you need to do next. Also, it doesn't hurt to keep a
notebook and a good digital camera with Macro capability on the
bench(es) to make notes and keep a photo record of how something was
assembled.

The camera on the workbench is a must. It's saved my bacon more than a few times, especially with complicated cabling. I now have one dedicated strictly to the workbench so it's always there when I need it.

Mark

Just letting you know there are currently a few of these left on ebay, in case you need one for your Tek 2335/6/7. Just ordered one for my 2335.


Tektronix 155-0220-00 Hybrid IC, vertical Amplifier Process 2336, 2336YA, 2337





Tektronix 155-0220-00 Hybrid IC, vertical Amplifier Proc... US $34.85 Used in Business & Industrial, Electrical & Test Equipment, Test Equipment



View on www.ebay.com
Preview by Yahoo

Any curve tracer (even the venerable 575) can do everything a Huntron
Tracker can do.

In fact a Huntron is just a simple one parameter curve tracer.



The thing that surprises me all the time is how many people think curve
tracers are only for measuring semiconductors.

Curve tracers are very versatile. What they can do is limited only by the
ingenuity of the operator.



Dennis Tillman W7PF

Steve Ditter mentioned Bob Pease' Improved Short Circuit Detector the other day so I hunted it down. It is quite simple, portable, battery powered, and provides audible feedback as you get closer to the short. I decided to make one for myself since it looked like such a good idea. It can be found at


You have to click on the "see the figure" link in the article to see the schematic.

Dennis Tillman W7PF

Will borrow another scope to check if the sweep generator is actually generates the sawtooth signal in auto mode.

Make sure you check all supplies are inside spec for ripple with your loaner scope. One plausible cause for false triggering is PSU ripple.


Good luck!