True RMS vs averaging DMM

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zamproject

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Exactly what makes the 8060A the best studio meter? or better put, what does the 8060A have (besides the now yellowish old plastic) that no other of the newer—and much better— meters have?
already answered by others, but I'll like to repeat :)
the direct dB reading (coupled with the REL function) is really helping in studio, for all kind of alignement/calibration, basic plot check, freq response or fc measure, compression att calibration etc...
I have once to resolder the pcb mounted banana plug, but never recap (for the moment...)
I compare various measures with my brand new 175....spot on...
 

abbey road d enfer

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The product I would like to buy apparently does not exist.
An auto-ranging DVM that displays simultaneously the DC content (average DC), the AC rms value and the peak-to-peak AC value. No need for AC average then.
The missing link netween DVM and 'scope.
 

JohnRoberts

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The product I would like to buy apparently does not exist.
An auto-ranging DVM that displays simultaneously the DC content (average DC), the AC rms value and the peak-to-peak AC value. No need for AC average then.
The missing link netween DVM and 'scope.
maybe invent a programmable hand held scope... You could use cursors to establish relative DC measurements from where to where. Of course this requires stable AC waveforms.

JR
 

abbey road d enfer

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maybe invent a programmable hand held scope...
I'm not up to the task. I have a hand held scope, but the numerical values are too small, and there's a lot of real estate used for buttons that would not be there if autoranging.
You could use cursors to establish relative DC measurements from where to where. Of course this requires stable AC waveforms.
Of course I wouldn't use it as a PGM meter.
 

Gold

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Maybe you could have installed a solar panel up in the canopy to gather more light Paul , never the less clearing an area in the vicinity of your cabin might be a good plan to prevent the chances of fire during the hotter summer months .
Above the canopy is over 30 ft up at least. It's remote. We are over an hours drive from the nearest hospital. I'm not doing work 30ft up. I don't even like climbing on the roofs which are only about 12 ft up. There are some open areas but none large enough that shadows wouldn't interfere. After over five years of trying everything else running electric from the road is the best solution. The only other feasible solution would be a slow quiet generator. They are expensive and need maintenance and fuel. The well pump is 2500W at startup. That's the major electric draw.
 

zmix

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The carrier is the sum of the two.
If 19/20 kHz are at 1:1 ratios the power sum is +3 dB.
I measured the average level, on multiple average-responding meters, to be about 1.4 dB lower when compared to the RMS-responding Fluke and RMS-responding FFT measurements which correctly show a +3 dB sum.

I don't think the 1.4 dB difference makes your bench work suspect.

I like Fluke the 8050A and also own an 8060 I used for field service.

Fluke_8050A_Collection.jpg


The pic is from when I had four, I now have five 8050As in my measurement stack.

One interesting trick I learned is that it can do dB measurements in the DC measurement mode.
For really accurate attenuator measurement I use DC as the stimulus.
The DC dB measurements come in handy.

The 8060s LCD display can often be repaired by cleaning the electro-tin-plated PC board contact to Zebra strip elastomeric connector "interface."
I use a dry Q-tip to burnish the PC board fingers.
When those are cleaned missing segments on the display will often come back to life.
I bought a replacement LCD years ago and never used it because I was able to refurbish the old one.

The 8050As are inexpensive on eBay and usually have two problems: Bad LCDs or NiCd batteries.
The batteries are easily-replaced and the unit won't run without them.
I had three of those 8050s..! I bought them from an electronics surplus store and they all had LCD issues - segments missing. I spent too much time trying to clean and re-seat the various flexible connectors and eventually gave up..


Is there a known fix for that problem?
 

inkster

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I love the 187 after being a staunch 8060A user for years...I use energizer lithiums and they last a long time for me and I use it every day.
I am always talking myself out of buying another 187 as I tell myself I've got 8060A's to utilize......
 

Dualflip

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already answered by others, but I'll like to repeat :)
the direct dB reading (coupled with the REL function) is really helping in studio, for all kind of alignement/calibration, basic plot check, freq response or fc measure, compression att calibration etc...
I have once to resolder the pcb mounted banana plug, but never recap (for the moment...)
I compare various measures with my brand new 175....spot on...
A huge amount of meters are capable of displaying dB, I understand its a useful feature but it is something ubiquitous in most of the high-end meters now.
 

Gold

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A huge amount of meters are capable of displaying dB, I understand its a useful feature but it is something ubiquitous in most of the high-end meters now.
None of the current compact Fluke’s do. The giant battery hog 287 does. The Agilent 1252 has been picked apart as has the Bryman. What others?
 

sodderboy

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The carrier is the sum of the two.
If 19/20 kHz are at 1:1 ratios the power sum is +3 dB.
I measured the average level, on multiple average-responding meters, to be about 1.4 dB lower when compared to the RMS-responding Fluke and RMS-responding FFT measurements which correctly show a +3 dB sum.

I don't think the 1.4 dB difference makes your bench work suspect.

I like Fluke the 8050A and also own an 8060 I used for field service.

Fluke_8050A_Collection.jpg


The pic is from when I had four, I now have five 8050As in my measurement stack.

One interesting trick I learned is that it can do dB measurements in the DC measurement mode.
For really accurate attenuator measurement I use DC as the stimulus.
The DC dB measurements come in handy.

The 8060s LCD display can often be repaired by cleaning the electro-tin-plated PC board contact to Zebra strip elastomeric connector "interface."
I use a dry Q-tip to burnish the PC board fingers.
When those are cleaned missing segments on the display will often come back to life.
I bought a replacement LCD years ago and never used it because I was able to refurbish the old one.

The 8050As are inexpensive on eBay and usually have two problems: Bad LCDs or NiCd batteries.
The batteries are easily-replaced and the unit won't run without them.
That's noice!
DC dB? You're blinding me with science. I'll try that tomorrow with the 8060A. I am bringing a new room into the world and the Fluke will be very busy.
And yes, there are internal connection issues that need to be addressed if they get wiggy, but I do not get much wigginess, touch wood. . .
Mike
 

JohnRoberts

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A huge amount of meters are capable of displaying dB,
most mechanical VU meters have dB scaling
I understand its a useful feature but it is something ubiquitous in most of the high-end meters now.
Back in the 1980s when I designed the TS-1 I incorporated a digital dB readout. It wasn't all that easy.

JR
 

sodderboy

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I checked it, and although the 8060A can calculate dB DC, I cannot think why I would need it.
On the DC scale I am testing blood pressure (+/-V) and nervous system (various) voltages to numerical values not converted to dB. I'll re-read the 8050A post.
"The plus rail is down 3 dB" said me never.
 

sodderboy

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Is there a known fix for that problem?
It's deeper than the ribbons. If it's like the '60A the LCD is connected to the PCB with a conductive rubber spacer that needs to have it's contacts cleaned. Have not had to do that often, but it works.
Mike
 
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