anyone have an oscilloscope to borrow?

[vmastro87 0]

Hey guys this might be a stretch but i have to adjust some equipment at work that has trim pots on it. Im not very familiar with adjusting them but I was told by the company they will work me through it if i can get my hands on one. Just cant seem to find anybody with one though. If anyone knows how to do this too my company would be happy to pay you to do it.

 

Thanks ahead of time
 

[Displaced Texan 9,058]

PLease PM me, I may be able to help.

What kind of equipment, and do you have schematics/specs/ect?

[djg0770 470]

I have a scope, you are welcome to use if you need it.  I do not know how to do what you are looking to do though.

 

I work in Asbury Park.

[vmastro87 0]

PLease PM me, I may be able to help.

What kind of equipment, and do you have schematics/specs/ect?

pm'ed

[vmastro87 0]

I have a scope, you are welcome to use if you need it.  I do not know how to do what you are looking to do though.

 

I work in Asbury Park.

awesome thank you! i will see what displaced Texan says and i will get back to you. i could meet you in AP to grab it.

[jm1827 274]

I have a scope as well that you can borrow if the others fall through.

[vmastro87 0]

you guys are all awesome as usual thank you, i will let you know for sure

[sosa9999 5]

How high of freq do you need it for. I could help as well.

[45Doll 4,294]

Now you've done it. I'll have to fire up my Tektronix 465B to see if it's still working. Great scope from the days of microwave troubleshooting and TV repair.

 

Sorry I'm too far away to be of help.

[vmastro87 0]

How high of freq do you need it for. I could help as well.

honestly this is a bit out of my feild. Though i have a good grasp of electronics and i have used a scope before ( a long time ago) im not quite sure exactly what im looking for. http://www.deva.co.uk/product/deva023.shtml that is the device im trying to adjust and it goes on whats called a CMM that uses linear scales and reader heads to interpret a position to check to high accuracy machined parts. 

 

this is the machine

http://www.publicsurplus.com/sms/docviewer/aucdoc/Brown%20Sharp%20Microval%20CMM%204.jpg?auc=496321&docid=2766514

[vmastro87 0]

while looking for the pictures i just found this literature from someone who has done the process, the blue text below outlines it. this was the process for our older machine but i would imagine it is very similar to this. 

 

 

 

Adjusting Brown & Sharpe MicroVal CMM Axis Quadrature Signal

11/25/09 - m. mcdade

Each 9-pin axis plug contains a small circuit board with
four pots for adjusting the quadrature signal waveforms.
I did not trace out and understand the exact function of
the circuitry supporting the sensors but at the time of
this work, both the x and y axes functioned well while
the z axis produced a 'axis error' message. Cleaning and
resetting the sensors on the scales helped (several years
ago, cleaning completely eliminated an error on the y axis)
but, eventually, the z axis could not be used any more and
required adjustment.

What I found was that the 4 pots on each little board in an
axis plug are associated with two test points on the counter
board in the cmm control (into which the plugs are inserted).
There are two test points for each axis. To adjust a given
axis, connect a scope probe for the 'upper' waveform (i.e.,
the one associated with the upper two pots when looking at
the plug board) to the upper test point and a scope probe
for the 'lower' waveform to the lower test point for the
axis. Set both channels to 2v/division on the scope and,
in auto mode, set the upper trace to the middle line of the
screen and the lower trace to the bottom line of the screen.
With power on and while moving the axis in question, you
should see sine waves from each channel. The top two pots
are used to adjust the upper signal (on the upper test pin
for the axis of interest). The upper pot of each pair sets
the offset of the waveform and the lower pot of each pair
sets the amplitude of the waveform. The following numbers
were derived by looking at the two good axes and served to
set the third so it now works perfectly. My z-axis voltages
were way off before my resetting and the fact that it
(mostly) worked for a long time indicates to me that these
are not terribly tight tolerance numbers.

top of upper waveform - 7.1 volts
bot of upper waveform - 2.7 volts
top of lower waveform - 3.5 volts
bot of lower waveform - 1.0 volt

---

Each scale unit has four pairs of emitters and sensors that
see out through a pattern of bars which one of the older
user manuals indicates are spaced a quarter space smaller than
the bars on the scale. It is easy to trace the wiring back to
the plugs and see that the pots on the plug are used to adjust
the voltage level to the emitters, apparently one per pot.
What isn't clear is how that translates to the two (unequal)
sine waves at the test points. These seem to form a
quadrature pair (the phase difference is clearly visible on
the scope) but how the circuitry gets from the four physical
signals to two logical ones is not clear to me.

[45Doll 4,294]

I'm not going to pretend to understand the calibration process for this machine from the above. but in general terms it appears you're adjusting the waveform to some specific levels. I'd want to know if the scope probe should be AC or DC coupled to the test points. (In other words are we measuring and adjusting absolute DC voltages, or an AC waveform?) With respect to the waveform, we can measure and adjust:

 

- The peak-to-peak sine wave amplitude

- The DC offset from zero (if any)

- The frequency (I don't see any evidence of that in the text)

- The phase difference between two wave forms (from the text it seems that will be fixed)

 

That's not a 'how to do it', but those are the typically available options.

[vmastro87 0]

I'm not going to pretend to understand the calibration process for this machine from the above. but in general terms it appears you're adjusting the waveform to some specific levels. I'd want to know if the scope probe should be AC or DC coupled to the test points. (In other words are we measuring and adjusting absolute DC voltages, or an AC waveform?) With respect to the waveform, we can measure and adjust:

 

- The peak-to-peak sine wave amplitude

- The DC offset from zero (if any)

- The frequency (I don't see any evidence of that in the text)

- The phase difference between two wave forms (from the text it seems that will be fixed)

 

That's not a 'how to do it', but those are the typically available options.

ok gothca, id imagine it is DC because the trim devices plug directly into a PCi card in a computer

[45Doll 4,294]

OK, so in typical fashion I decided to read the manual, which I hadn't done. Now I think I see  it.

 

The scope should show you a Lissajous pattern. (https://en.wikipedia.org/wiki/Lissajous_curve) That's the summation of two sine waves where one is driving (displayed on) the scope X-axis and the other is driving the usual Y-axis. Please note this; it is not two scope probes on two scope Y-axis ports with the X-axis trigger being derived from one or the other and comparing the phase offset of two signals in time.  I used to use this technique to 'see' the quality and separation of an FM Stereo broadcast signal.

 

Now see page 1 of the DEV023 manual. The four trim pots are marked with four phase numbers: 0, 90, 180, 270. I would expect these trim pots to adjust the Lissajous pattern until it's symmetrical. When symmetrical, the two sine waves are properly related. Probably a DC offset is not relevant.

 

The company website has a support email address. If I were you I'd email them and ask for a specific calibration procedure. There might be an optimal sequence of adjustment, since you're working with four trim pots. I'd also ask for the specific Lissajous pattern they're looking for.

[Sota 1,174]

45doll: you should just see if the OP's company really will pay you to do the job instead.

[45Doll 4,294]

45doll: you should just see if the OP's company really will pay you to do the job instead.

LOL! Wouldn't be the first time. Well, the OP is down in Jackson, so I'm not sure it would be cost effective.

 

Seriously, if you get the scope setup correctly adjusting for the pattern should be fairly straight forward. I'm pretty sure symmetry is what he'll be looking for. But if I was him I'd like a little guidance from the factory first. You really need to know what you're looking for.

 

Oh, I yearn for the bygone days of hp microwave troubleshooting. (That's Hewlett Packard, the old one.)

[W2MC 1,663]

Wow....actual electrical engineering breaking out in the NJ Gun Forum...

[45Doll 4,294]

Wow....actual electrical engineering breaking out in the NJ Gun Forum...

Hey... I'm the former KV2M. I'd still be if I hadn't let my license lapse. Dummy! And I actually passed the 20 WPM code test. You know, back in the Mesozoic era.

 

Anyone want to talk about storage normalizers? (OK, just kidding.)

[DeerSlayer 241]

I have a scope too. I'm in Sussex County, not sure if that's further from everyone else or not for you.

[W2MC 1,663]

Hey... I'm the former KV2M. I'd still be if I hadn't let my license lapse. Dummy! And I actually passed the 20 WPM code test. You know, back in the Mesozoic era.

 

Dood!....you had t-w-o years! - shouldn't have let your ticket lapse!

 

I know the current KV2M...she's not giving it up anytime soon

 

But you CAN get your ticket back fairly easily.  You do have to re-take element 2 (Technician) so that you have a license again, but you have "lifetime" credit for Element 3 (General) and Element 4 (Extra), as long as you can prove you once held an Extra ticket...so you don't have to take those tests again. 

 

So DO IT!  get your ticket back!

[45Doll 4,294]

LOL! She called me way back when to have me turn in the KV2M plates on my truck, which I never turned in after I realized my license had expired. Give her my regards.

 

My Amateur Extra Class certificate is hanging on my office wall right next to my commercial First Class Radio Telephone Operator license (now defunct and meaningless with today's broadcast equipment). You mean if I take element 2 and pass they'll reinstate my Extra license with a different call sign?

 

Sorry to the OP for this deviation, but this could be important! I'll pick it up in a PM if necessary.

[W2MC 1,663]

LOL! She called me way back when to have me turn in the KV2M plates on my truck, which I never turned in after I realized my license had expired. Give her my regards.

 

My Amateur Extra Class certificate is hanging on my office wall right next to my commercial First Class Radio Telephone Operator license (now defunct and meaningless with today's broadcast equipment). You mean if I take element 2 and pass they'll reinstate my Extra license with a different call sign?

 

Sorry to the OP for this deviation, but this could be important! I'll pick it up in a PM if necessary.

YES

 

https://www.laurelvec.com/?pg=faq

 

look under "grandfathering"

 

 

SJRA conducts exams on the second Wednesday of every month in West Berlin NJ

 

(oh, and they wanted 'his n hers' for their hondas.  her husband is KV2R (Richard) - she is KV2M (Mary)

[45Doll 4,294]

Yes, I remember the pairing up story. Glad they're still enjoying them.

 

I'm looking at Element 2 question pool now. This could be a no-brainer. Thanx! I'll keep you apprised privately.

 

73

[vmastro87 0]

Wow....actual electrical engineering breaking out in the NJ Gun Forum...

i know im very impressed lol!!! I have been talking to displaced texan and it looks like im going to borrow his scope to give this a shot. Between his knowledge and everyone else on here im pretty confident i can do it. If not we will definitely be paying someone to do it. The company is located in bayville.

 

LOL! She called me way back when to have me turn in the KV2M plates on my truck, which I never turned in after I realized my license had expired. Give her my regards.

 

My Amateur Extra Class certificate is hanging on my office wall right next to my commercial First Class Radio Telephone Operator license (now defunct and meaningless with today's broadcast equipment). You mean if I take element 2 and pass they'll reinstate my Extra license with a different call sign?

 

Sorry to the OP for this deviation, but this could be important! I'll pick it up in a PM if necessary.

all good i dont mind at all with all the help you guys are giving

 

 

http://olympic-tool.com/

[45Doll 4,294]

all good i dont mind at all with all the help you guys are giving

 

 

http://olympic-tool.com/

Good. Glad to see a M&T company is still alive and well in the U.S. I see you're actually around Toms River. I thought you were all the way down in south Jersey. I'm up in Sussex county so it would be a hike for me, otherwise I would have offered mine.

 

Let us know how you make out. Firearms are important, but I made my living with many forms of electricity!

[misterwhisker 4]

If you still need one, I have a Fluke Model 95 Scopemeter and I also live in Jackson.

 

You are more than welcome to borrow it for as long as you need it.

 

Just PM me.