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1
Eeeeeeh. I have a JBC JT-A. It costs about $1600. The quick is under $300.

Is the JBC $1300 better than the Quick? No.
Is the JBC $600 better than the Quick? Maybe.

The handpiece has an antimicrobal texture, and is also slimmer. The Quick 861DW has a fat base. Think of it like trying to write with a sharpie vs. writing with a lysol can. The JBC is quieter, does not cause any disturbance in the room's electricity as well. It's just a higher end piece of kit.

It is egregious that the JBC costs $1600 while the Quick costs $300, but the JBC is better. Especially if you are working on things that require great accuracy, or if you are working for 12 hours a day. It is a joy. I cannot for reasons of practicality justify spending $1600 on a standard desk hot air station, so even though I could afford it, I use the Quick.

Not to mention that the JBC JT-A heating element by itself costs about $205-$220. I'm never buying another JBC station at those prices. I understand if the station were cheap, that they need to make the money back by upping the cost of the heating element. But at $1600+ for the station, $205-$220 for the heating element is an unwelcome kick in the groin.
I was meaning performance, not feelings. Yes JBC JT-A is slimmer and looks better, but offers only 40% of the max airflow compared to 861DW, no wonder it's quieter. 861DW at such airflow is extremely quiet as well. JBCs max 50l/min is already lower that what I generally use (~60-70l/min), not to say I often use max airflow (120l/min) as well.
2
Are you waiting for Royal Mail to bring you something?

You might be waiting a long long time.

3
Eeeeeeh. I have a JBC JT-A. It costs about $1600. The quick is under $300.

Is the JBC $1300 better than the Quick? No.
Is the JBC $600 better than the Quick? Maybe.

The handpiece has an antimicrobal texture, and is also slimmer. The Quick 861DW has a fat base. Think of it like trying to write with a sharpie vs. writing with a lysol can. The JBC is quieter, does not cause any disturbance in the room's electricity as well. It's just a higher end piece of kit.

It is egregious that the JBC costs $1600 while the Quick costs $300, but the JBC is better. Especially if you are working on things that require great accuracy, or if you are working for 12 hours a day. It is a joy. I cannot for reasons of practicality justify spending $1600 on a standard desk hot air station, so even though I could afford it, I use the Quick.

Not to mention that the JBC JT-A heating element by itself costs about $205-$220. I'm never buying another JBC station at those prices. I understand if the station were cheap, that they need to make the money back by upping the cost of the heating element. But at $1600+ for the station, $205-$220 for the heating element is an unwelcome kick in the groin.
I was meaning performance, not feelings. Yes JBC JT-A is slimmer and looks better, but offers only 40% of the max airflow compared to 861DW, no wonder it's quieter. 861DW at such airflow is extremely quiet as well. JBCs max 50l/min is already lower that what I generally use (~60-70l/min), not to say I often use max airflow (120l/min) as well.
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Test Equipment / Re: List your test equipment "scores" here!
« Last post by Ice-Tea on Today at 08:38:44 PM »
Picked up the free 8664A. F*ck it's heavy. I have to check what the calibration code means.

Does it still have the sticker that says you need to carry it with 2 people? (not a joke...)
5
I'm really upset with the latest Windows 10 updates/upgrades.
I carried my laptop to a friend's office as a temporary solution to drive a special printer whose driver had been crashed by one Windows 7 update.
I was in a hurry, and even if I was able to restore (easily) the Win 7 machine, I left the laptop connected to allow them to finish some urgent work.
They could not: Windows 10 wanted to update (some hours), and the result was that the update went bad, and it was automatically removed, and the day after the cycle began again: update, remove update, and so on... Windows did not gave me an explanation (or maybe it did, but where can I find it?).
After one full week I was really VERY upset, so I took my Win 7 DVD and installed Win7....
What I saw was a total loss of respect for the paying customer. The want MY computer to do what THEY want..
I'm not a real IT tech, but I have some experience, and this is unacceptable.
STOP.
6
Test Equipment / Re: List your test equipment "scores" here!
« Last post by scatha on Today at 08:36:46 PM »
Picked up the free 8664A. F*ck it's heavy. I have to check what the calibration code means.

It means the equipment values itself as $8043311 worth

Nah, its the number of calories burnt lugging the thing up the stairs.
7
Yes. A Chinese company was exporting cellphone jammers to US for years, and it was fined by FCC tens of millions of dollars in 2016.

Heh.  How is that payment coming along?

Don't know, it was a fairly big private company, and it made headlines in China. I guess either the company paid the fine and sell to government/military, or the company said F you and withdrew from US market.
8
Test Equipment / Re: bg7tbl gpsdo master reference
« Last post by gr8tfly on Today at 08:35:14 PM »
Here's another shot of the main board that's not cropped. I realized the reflections around the ublox in my first attachment blew out the jumpers a bit. I was more focused on getting all the main components, especially the Atmega's, part numbers to show up.

Chuck
9
Test Equipment / Re: Owon XDS3062A input noise (good) and glitches (bad)
« Last post by rf-loop on Today at 08:34:22 PM »
I took a closer look at  the 12-bit Owon scope to compare the input noise levels to other scopes. Here are the RMS noise for 50 Ohm shorted inputs. It does not depend very much on the time scale of the scope.

Shorted RMS noise   1mV/div        1 V/div
TEK TBS1064          250 uV          16 mV
Instek GDS-1054B  95 uV            14 mV
Micsig TO1104        85 uV            10 mV
Owon XDS3062A     45 uV            3.3 mV

So on high sensitivity settings Owon input amplifier has about a factor of 2 lower noise. On higher voltage settings the 12-bit ADC has about 1 LSB RMS noise, while the 8 bit ADCs are limited by 1-bit flickering.



Is it good?  Not very bad at all but also not very good. (I have here also This Owon 100MHz 3kXA and these some tests can find around forum older messages)



Here for compare Siglent.
500uV/div  20M BW  RMSnoise 27uV
1mV/div 20M BW RMSnoise 30uV

RMSnoise equals SDEV (in this case. It removes mean so it show this noise RMS without possible DC offset. This can use because we measure noise and we are interested only amount of noise itself)
(random noise mean (DC - offset) removed)

Here comparable image for Owon 1mV/div with forced 20M BW. (Because Owon do not have full bandwidth available)

10
Before, I reverse this, maybe somebody already has a schematic of this controller they would share.
Thanks!

https://www.ebay.com/itm/12V-40V-10A-PWM-DC-Motor-Speed-Controller-with-Knob-D7Y1-/172622352700

I have traced it out and drawn it in a haphazard schematic, and then did a search for a similar circuit using search term: 555 pwm motor speed control
Happily, I found this schematic which is essentially the core of what I extracted.  The only difference is that I found a protection diode in series with the power supply connection and a constant current diode feeding a zener diode, providing the positive supply. 

But as far as the pwm circuit, I extracted the identical implementation as shown in this schematic.
Why not use a MOSFET for Q1? It will have a much lower power loss, than a Darlington pair.

The TIP122 is also only rated to 5A continuous, so no good for 10A.

47R is probably too low for the base resistor. The maximum base current of the TIP122 isn't specified on the data sheet, but it's certainly less than the >200mA that would flow, when there's a 12V power supply. The NE555's maximum output current rating is also only 200mA, so you're pushing it to the max.

https://www.onsemi.com/pub/Collateral/TIP120-D.PDF
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