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Thanks to OP for upgrading Apollo 8 title to Apollo 11    :-+ 

FWIW, all this numbering business can be very confusing,
I'm still searching the internet for Windows 9   :-//

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I don't know about the approval being genuine or not but this doesn't seem dangerous, just cheap and nasty. I've seen similar things before.

As with many devices with generic lamp holders, the greatest danger is user error: someone replacing the lamp with a more powerful one and it overheating, causing a fire.
3
Buy/Sell/Wanted / Re: Please help me get a oscilloscope
« Last post by Electro Detective on Today at 06:35:22 PM »
Get a job.  Earn some money.  Buy one.

Pretty piss poor advice. As others have pointed out, it's not that easy, in fact, most countries have a minimum age where someone can be legally employed and be paid. In Australia it's 14 years and 9 months old. That's when I got my first job.

I respect the kid, he knows what he wants and he is doing his best. At least he has a keen interest in something useful, not hanging out with a "bad crowd" or wasting his day away at a skate park.

 :-+ 

...and he's hooked up with one of the better forums   :clap:



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Test Equipment / Re: The Summary Siglent SDS1202X-E Thread
« Last post by rf-loop on Today at 06:35:19 PM »
One of the uses I have for X-Y-Mode is a very simple task for a scope (or at least it should be): In the field of musical instruction I want to show musical students the so called phenomenon "beat frequency", that is, if you detune for example a perfect fifth a bit, you will hear a more or less significant wow and flutter. For example, if you have the two frequencies 400 Hz and 600 Hz and you will detune the 600 Hz to 601 Hz you will hear this beat frequency, it will be a wailing of the sound with the resulting frequency of 1 Hz. (And 0,1 Hz at 600,1 Hz, 0,2 Hz at 600,2 Hz and so on.)
Using the X-Y-Mode of a scope will show this phenomenon simply, because the pattern on the screen will move with the frequency of 1 Hz. And seeing the phenomenon will help to identify and hear it more precise.

But if the scope will be too slow in this mode, the pattern will not move smooth, but will jump jerkily, and this will not help at all to to make the beat frequency visible. So does the 1202X-E (resp. did with the old firmware as I could state).
Unfortunately it will be a shame for a scope with this comparatively modern and fast hardware. Even my first scope, the GW-Instek GDS 1022 manages this simple task with a smooth screen update and movement - and this is certainly one of the most basic scopes ever!
I wanted to replace this simple scope with a more modern one with a much better screen, but i this regard the Siglent seems to fail completely  >:(

By the way, this is not the only task for that I will use a scope. I am musician and I will use it also for maintaining and in case it fails my technical gear. But  the task I described above is a very useful task in my educational practice.

Siglent XY mode looks like it is not at all true XY mode.
 It looks like it is derived from bacround running YT mode (without history buffer).  If it is (and I believe it is).  This may explain why in XY mode there can also do full set of automatic measurements, includind also phase-angle what really is not measured from screen memory, as also example risetime etc. ERES works, wfm average works. (also trigger works )  For build whole XY display it need use lot of YT acquisitions. This is perhaps reason what makes it some slow. Some good, some bad.

Images have same signal. First XY mode and then YT mode.
It can see that it keep same measurement resolution in both modes. With this setting, 7M memory and 500MSa/s XY update speed is quite slow. Roughly in 1 second class.

Of course if this scope do real XY plot from ADC directly to display map memory  it can be very fast. nearly like analog scope without ADC resolution and noise limits.

What I hope is that Siglent add also fast true XY mode. Yes then loose some things but get high speed and perhaps can add even intensity gradation(?).






(my mistake, in this image cursors irrelevant)
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Projects, Designs, and Technical Stuff / Re: Rigol Scope shorting out
« Last post by alm on Today at 06:34:49 PM »
I just got a rigol DS1024Z
Are you sure this model is correct? I could not find any reference to it.

A modern amplifier works with a carrier on the order of 30-50Vpp at a few hundred kHz. Could be enough to get a tiny spark into a capacitive probe.
A few hundred kHz at 50 Vpp should be well within the limits of a 10x probe or even a scope with 1x probe. The Rigol PVP2150 is specified up to 300 VRMS from DC-400 kHz, and derated by 20 dB/decade until ~10 VRMS (see attachment). I could not find a similar graph / data in the DS1000Z manual or datasheet, so apparently that is too much effort for Rigol. A random Tek DSO was limited to 300 VRMS until 2.5 MHz, derated by 20 dB/decade to 50 V above 2.5 MHz. So neither should have had a problem with a few hundred kHz at ~18 VRMS. Assuming the DS1000Z has a similar voltage limit.
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General Chat / Re: What did you buy today? Post your latest purchase!
« Last post by SeanB on Today at 06:29:56 PM »
Everything keeps falling off..... Toyota.
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Do a 4 wire resistance measurement of a 1 Ohm resistor and compare the noise level.

Any kind of RF transmitter, phone, wireless router, neighbors router and so on can have a significant influence on the digits, especially when you measure a 100k resistor with 2 wires. I don't think there is something wrong with your 34465A.

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General Chat / Re: Audiophile Ethernet card! Finally!
« Last post by Simon on Today at 06:17:12 PM »
The best thing you can do is install a PCI audio card as it puts the analogue stuff further away from the unshielded digital stuff on the motherboard causing lots of noise. But I just used an old sound-blaster card that I moved from PC to PC ignoring the onboard sound-card with analogue amplifiers sitting in the middle of digital busses. Have they bothered to come up with an overpriced shielded soundcard ?
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Hello,

Photos of your setup?

Did you only measure the temperature sensor (directly at the TEC) or some components more far on the PCB?
But on the other side: a 5V 1.5A TEC is shurely only intended to cool single chips.

With best regards

Andreas


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Projects, Designs, and Technical Stuff / Re: 400 V Square wave oscillator
« Last post by kridri on Today at 06:14:59 PM »
You can het inspired by looking to some older crt schematics. Especially the high speeds scopes have a broadband 'high voltage' (around 300-400V) x and y deflection drivers.
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