COP 17 Heater | Rosemary Ainslie

[jibbguy]

That is great news

For many years when i worked in the industry, we were in direct competition with Tek in the DSO market. But i always admired them and knew that their products were better made, and better supported, than any of our other competitors'.

And besides, they always had the best "Freebees" at trade shows

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DC offset will show up easy enough: Just set the scope channel to "DC coupling", at "25mV per div" (or the highest gain range)... And press the "GND" button.

[poynt99]

The DC volt meter measurement across the shunt will be very accurate in terms of net voltage polarity, provided the meter reads "0.000V" with the leads shorted and with it on the most sensitive scale (or the scale that will be used for the measurement). The validity of the meter as a polarity indicator can be easily verified by anyone with a FG and meter as I have already posted. The accuracy of this polarity indication can also be easily checked.

The purpose of this measurement is to compare against the real-time Tek scope measurement across the shunt to determine if the net polarity indication on the scope is correct.

.99

[Harvey]

Guys - very good news and many thanks to Lisa - we've been given another month's use of our Tektronix. Cannot tell you how grateful we all are Lisa. Many thanks indeed.

[Harvey]

The DC volt meter measurement across the shunt will be very accurate in terms of net voltage polarity, provided the meter reads "0.000V" with the leads shorted and with it on the most sensitive scale (or the scale that will be used for the measurement). The validity of the meter as a polarity indicator can be easily verified by anyone with a FG and meter as I have already posted. The accuracy of this polarity indication can also be easily checked.

The purpose of this measurement is to compare against the real-time Tek scope measurement across the shunt to determine if the net polarity indication on the scope is correct.

.99

Have a look at the manual for the 3054 (its available online) and tell me what you read there regarding the need for calibration - sort of steals your thunder here eh?

So...what did you learn from Tektronix regarding how the scope reads frequency? Willing to admit you were wrong about the peaks?

After all this is said and done - a Mariner with 2 compasses will never know which is correct. Your test using a DMM introduces the second compass. You either need to trust the one, or you need 3.

[poynt99]

Willing to admit you were wrong about the peaks?

Admitted. Yes.

.99

[Joit]

Dont forget to put a Tinfoil Hat at your Head when you do the measurements. /_\
You can probatly strew electrostatic Energy into the Circuit from your Hairs. mmmhmm.

[Tecstatic]

Aaron,
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I am quite willing to consider the possibility that a circuit or device might exhibit strange behaviour, even OU behaviour. That's one reason why I partake in these forums.

However, before I decide to invest any time and effort on something, it's only logical to investigate the phenomenon fully to the best of one's abilities in an attempt to explain what is observed by conventional means.
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.99

Yes. and please do explain that from your own experiments.

I am <not> quite willing to consider your endless posts advising how to measure when you could do it yourself, and save my time reading "noise" posts, so now you qualify for my personal ignore list (so you can save your time commenting this post).

Should you however start doing experiments, so I see other members gaining value from you, then I will remove you from my ignore list.

Eric

[poynt99]

Have a look at the manual for the 3054 (its available online) and tell me what you read there regarding the need for calibration - sort of steals your thunder here eh?

The SPC routine optimizes the oscilloscope signal path for maximum
measurement accuracy. You can run the routine anytime but you should always run the routine if the ambient temperature changes by 10 °C (18 °F) or more.

What is stated in the manual makes perfect sense. Please explain your point and what thunder?

Are you presuming that the scope has been SPC calibrated recently by someone before Aaron received it?

Are you presuming that the scope was previously SPC calibrated in an environment that was within the specified 10ºC window compared to Aaron's environment?

Are you presuming that a temperature drift of less than 10ºC doesn't affect the scopes accuracy?

Are you presuming that Aaron SPC calibrated the scope prior to his measurements?

Are you presuming that taking measurements down in the fractional mV range does not call for an accurate instrument?

Edit: Are you suggesting that the scope's SPC routine does not need to be run and Aaron's test redone?

Please clarify your statement.

.99

[jibbguy]

Poynt, i was referring to the scope's calibration for DC offset, not anything to do with the signal. And i forgot to mention the leads must be shorted first lol (which would have made that more apparent... Me bad )

Also, regarding that tech support reply, these probes appear to not be "active": Having a "Trim" variable cap screw for tuning, and a "x1/x10 switch" does not mean they are Active... Which usually refers to optional high-impedance Logic, High Voltage, or Isolation Probes. But if Aaron wishes to stop the inevitable question lol, he could just quickly use a BNC cable with a banana adapter at the end and short it, as a check for any difference in offset.

But i gotta say Poynt, that DMM horse is decomposing; you can stop flogging it now

The problem is NO ONE would take the data seriously anyway no matter what the result. It's just too subjective to be of any use at all. Please step back a minute and consider how useless it is to do a measurement that is beyond the capability of the device to perform.

[poynt99]

Also, regarding that tech support reply, these probes appear to not be "active": Having a "Trim" variable cap screw for tuning, and a "x1/x10 switch" does not mean they are Active... Which usually refers to optional high-impedance Logic, High Voltage, or Isolation Probes. But if Aaron wishes to stop the inevitable question lol, he could just quickly use a BNC cable with a banana adapter at the end and short it, as a check for any difference in offset.

You are reading too much into David's response. He does not know what kind of probes Aaron is using, and I did not mention probes to him. He was simply pointing out that IF active probes were used, they need to be warmed-up to stabilize as well.

But i gotta say Poynt, that DMM horse is decomposing; you can stop flogging it now

The problem is NO ONE would take the data seriously anyway no matter what the result. It's just too subjective to be of any use at all. Please step back a minute and consider how useless it is to do a measurement that is beyond the capability of the device to perform.

You tried it did you? The measurement works.

It's quite puzzling that folks will put blind faith into something that is statistically quite improbable such as this net negative current ordeal, yet they will ignore solid grounded science from their own discipline that is not commonly applied perhaps, but quite easily demonstrated. The DC DMM method to determine net polarity works and it is accurate. I surmise that a video demo would not be convincing enough.

.99

[witsend]

It's quite puzzling that folks will put blind faith into something that is statistically quite improbable such as this net negative current ordeal, yet they will ignore solid grounded science from their own discipline that is not commonly applied perhaps, but quite easily demonstrated. The DC DMM method to determine net polarity works and it is accurate. I surmise that a video demo would not be convincing enough.

.99

This isn't my quarrel here but may I ask - why is a video demo not convincing enough? What would convince you? This is really getting laughable. It seems that there is no way that this argument can then be presented. What proof do you require here? I'm just so sorry that Aaron wasted so much time on making that video to show you the polarity bias from the ammeter - and then another to prove he was not distorting the values in the first video? Neither cut it? Nor ever will? Golly. By refusing to accept the data presented - then you've won this argument hands down.

[poynt99]

Rosemary,

I have to tell you, every post of mine--you consistently mis-interpret at least part of it, just as you did again just now.

The video not being convincing is from "your guys'" perspective. If I do a video demonstrating the DC voltage meter method of determining net polarity that is.



.99

[jibbguy]

It is not a question if it working IN THIS CASE or not. It goes to credibility.

You know, we are "using" you... To discover and learn in advance what will happen when this circuit is attacked by professionals in the wider world (as it certainly will be once public awareness of it grows ). So far you have done us a service in that respect, and we can even be somewhat grateful for it. But here, the service is not helpful.

I, and anyone else with half of my background, could give you AT LEAST FIVE reasons off the bat why such readings could be false and completely untrustworthy; and therefor not wise to pursue...And if it was included in the claims in any way, will only act as a red herring to attack the GOOD data.

[witsend]

Rosemary,

I have to tell you, every post of mine--you consistently mis-interpret at least part of it, just as you did again just now.

The video not being convincing is from "your guys'" perspective. If I do a video demonstrating the DC voltage meter method of determining net polarity that is.



.99

Sorry. If that's what you meant. I'm inclined to misread and jump to conclusions. It's my only fault. However and to the poynt. Are you seriously proposing to do this test? And do a video demo? Who could reasonably object. I, for one, would welcome it. I will never be happy about using an ammeter in series as detailed in OU.com. But I would LOVE to see you replicate. Come on Poynt. How about it? It's long overdue and you've been sitting in that armchair far too long. I think you'll enjoy the exercise.

[poynt99]

Once again you are reading incorrectly into my posts Rosemary.

The contention here with Jibbguy et al is that my proposed DC voltmeter test is invalid and/or inaccurate.

The video demonstration would be to validate the use of a simple conventional DC voltage meter set on DC volts to determine the net polarity of a high frequency low amplitude AC voltage (any wave form) applied to its input terminals. I trust that is clear enough.

.99