Test Equipment Anonymous (TEA) group therapy thread

[McBryce]

Pretty sure it has RIFAs inside.
(Attachment Link)

Are those bricks slanted or is your desk seriously tilted??

My guess is: it is a round room.

And a round table, yes

Ok, but in a round room with a round table*, the surface of the table and the mortar between the bricks should be parallel to each other?

McBryce.

* With the same centre point and radius.

[FransW]

I was thinking about the IQB (IQRB1 ±0.05ppb) and Suntsu (SRO10S ± 0.05 ppb) mini-rubidium oscillators with  a mtbf figure of 100000 hrs (11 years).
Both on the market since 2019.
Specs attached.

I bought a refactored and calibrated Datum LPRO 101 from user Testpoint1 last year. Has been working fine since then. I'm planning to put it in a box with a linear power supply and distribution amplifier.

First: congrats with you acquisitions.
I use a double Oscilloquartz Star 4 OEM system with my BG7TBL analyser with which I am quite happy.
What I in practice see are cable length and quality differences in the micro Hz region. All on switched psu's and in a stable non-vibrating environment.

When I think about the shortest possible (sofar) time step (the Planck time) I feel very comfortable with my system and the assistence from NIST/BIPM.

Have fun, owning is different.
Regards, Frans

[mnementh]

I could repurpose the Dell 5200 into a XP machine, I have a licensed copy of XP, not that matters if its not being connected to the internet anyway 

actually you have to activate it, and they have shutdown the activation servers. Which means you have to activate it over the phone.

Only for bundled SP2 & later. You don't want that for MAME anyways; SP2 was where they went full HAL and essentially made you play in a VM on your own computer. VERY poor implementation. SP1 & earlier was the last you actually OWNED your PC.

mnem
*shudder* "I felt a great disturbance in The Ports; as if millions of users screamed out in agony, and were suddenly silenced..."

[Ice-Tea]

Pretty sure it has RIFAs inside.
(Attachment Link)

Are those bricks slanted or is your desk seriously tilted??

My guess is: it is a round room.

And a round table, yes

Ok, but in a round room with a round table*, the surface of the table and the mortar between the bricks should be parallel to each other?

McBryce.

* With the same centre point and radius.

You're overthinking it. Perspective. Lens. Some tilt of the table due to prvious boat anchors. It's fairly parallel if you're at eye level with the table.

[BU508A]

You're overthinking it. Perspective. Lens. Some tilt of the table due to prvious boat anchors. It's fairly parallel if you're at eye level with the table.

We need proof. Send more photos.    
You can add a HP calculator for comparison, this is very appreciated here. 

[mnementh]

You could really fuck with their heads... take the pics with a GoPro. 

mnem
 

[Specmaster]

I could repurpose the Dell 5200 into a XP machine, I have a licensed copy of XP, not that matters if its not being connected to the internet anyway 

actually you have to activate it, and they have shutdown the activation servers. Which means you have to activate it over the phone.

Only for bundled SP2 & later. You don't want that for MAME anyways; SP2 was where they went full HAL and essentially made you play in a VM on your own computer. VERY poor implementation. SP1 & earlier was the last you actually OWNED your PC.

mnem
*shudder* "I felt a great disturbance in The Ports; as if millions of users screamed out in agony, and were suddenly silenced..."

What differance does it make then with SP1 and SP2 if it is not connected to the internet?

[Specmaster]

You're overthinking it. Perspective. Lens. Some tilt of the table due to prvious boat anchors. It's fairly parallel if you're at eye level with the table.

We need proof. Send more photos.    
You can add a HP calculator for comparison, this is very appreciated here. 

A decent calculater needs an = key for balance 

[mnementh]

I could repurpose the Dell 5200 into a XP machine, I have a licensed copy of XP, not that matters if its not being connected to the internet anyway 

actually you have to activate it, and they have shutdown the activation servers. Which means you have to activate it over the phone.

Only for bundled SP2 & later. You don't want that for MAME anyways; SP2 was where they went full HAL and essentially made you play in a VM on your own computer. VERY poor implementation. SP1 & earlier was the last you actually OWNED your PC.

mnem
*shudder* "I felt a great disturbance in The Ports; as if millions of users screamed out in agony, and were suddenly silenced..."

What differance does it make then with SP1 and SP2 if it is not connected to the internet?

IIRC, SP1 or SP2 is when they started making XP phone home to authenticate. Prior to that, it authenticated against a hash internally.

mnem
 

[McBryce]

You're overthinking it. Perspective. Lens. Some tilt of the table due to prvious boat anchors. It's fairly parallel if you're at eye level with the table.

We need proof. Send more photos.    
You can add a HP calculator for comparison, this is very appreciated here. 

A decent calculater needs an = key for balance 

What better example of Parallel than an equal sign.

McBryce.

Oh No! I've accidentally taken sides in the never ending calculator battle! Oh, I know, I'll post a picture of my TI-84 Plus which isn't RPN but also doesn't have a button with an equal sign, that will confuse the fü@k out of them put me back on neutral terrain.



 

[Saskia]

I still have a couple of Casios floating around. Sold all my expensive TIs after some people ripped them outta my hands.

[bd139]

Oh No! I've accidentally taken sides in the never ending calculator battle! Oh, I know, I'll post a picture of my TI-84 Plus which isn't RPN but also doesn't have a button with an equal sign, that will confuse the fü@k out of them put me back on neutral terrain.

Still shifted exponent. Tut tut. Shake head.

Would have some street cred if it was a TI81, 85 or 86. Those were ok.

Edit: just to note I was in calculator arbitrage. Basically you buy all the calculators at the end of the school term on ebay then sell them again at the start. Made quite a bit of money out of the TI83 here 

[mnementh]

https://securitytoday.com/articles/2020/04/24/covid19-thermal-cameras-start-to-hit-the-marketplace.aspx

Jeebus.

mnem
You can't make this shit up...

[McBryce]

My school calculator was a Sharp EL-512 which I still have and use, but I didn't have a choice in the matter, it was a group-buy from the school.

However, when it comes to buttons and shift functions... Real mens Calculators don't have buttons (in case you're wondering about those propellors, my sons mini-drone had an incident with a wall today).

McBryce.

[Specmaster]

You're overthinking it. Perspective. Lens. Some tilt of the table due to prvious boat anchors. It's fairly parallel if you're at eye level with the table.

We need proof. Send more photos.    
You can add a HP calculator for comparison, this is very appreciated here. 

A decent calculater needs an = key for balance 

What better example of Parallel than an equal sign.

McBryce.

Oh No! I've accidentally taken sides in the never ending calculator battle! Oh, I know, I'll post a picture of my TI-84 Plus which isn't RPN but also doesn't have a button with an equal sign, that will confuse the fü@k out of them put me back on neutral terrain.



 

Good idea, I'll even up the score a bit with photo of my 2 TI84 emulators as well 

[bd139]

I love that the normal nSpire doesn't have shifted exponent but the TI 8x keypad for it does because literally the things are taught using muscle memory and if anyone moved a key all the mathematics teachers would turn into a molten gibbering mess.

[Specmaster]

And for good measure, I'll post this one, no = key or ENTER key in sight 

[URI]

But what about something easier to accomplish first?
Looking at that BG7TBL FA-2 counter I see lots of resolution when taking samples with a gate time of 10s.
Seems to be very much maths involved, so what's the precision of that unit?

Supposed to be something like 11digits. I double checked with the HP 53310a and they agree to around +- 0.1 mHz

I searched for the FA-2 a bit and came across a thread here in the eevblog forum:
https://www.eevblog.com/forum/metrology/bg7tbl-fa1-frequency-analyzer/msg2844668/#msg2844668

There's a comparison between a HP 53131A (spec: 10 digits/sec) and the FA-2 (spec:11bits/sec) that suggests that the specs of the FA-2 might not be plausible in all aspects.
Did you compare both counters at equal gate time?      

Perhaps you should first check with a decent counter with high resolution and high precision, for example some nice gear from HP/Agilent/Keysight (53132A, 5370A or newer ones), Fluke/Pendulum (PM91,CNT-91), Stanford Research (SR 620).
I surely missed some. Any further suggestions?   

I was partially joking with the Cesium reference. Honestly, I only really need an accuracy of 1hz at 10Mhz. So I got plenty of resolution with the FA-2 and HP 53310a.

It's never too late to get better/more interesting TE!   
You remember the purpose of this thread? Your argument having enough resolution is void here..   

Secondly, can you improve your GPS antenna setup?
With a good view of the sky and a good antenna you could explore how different GPSDOs compare (even better with step one accomplished -better counter..)   

This is a good point. My setup is really ghetto right now (the antenna standing on the side of my pool). I'm planning to put an antenna on the roof but none of my GPS antenna are working with my Rohde & Schwarz ED170MP. The ED170MP is supplying 15V but my antenna only goes to 5V max. So I tried supplying 5V externally with a biastee but look like the ED170MP doesn't like that. I need to contact Meinberg (the producer of the ED170MP) to see if they can recommend an antenna.

What exactly does your Meinberg ED170MP not like?
Is it monitoring the current of the 15V antenna supply? -> Build a dummy current device could be the solution.

[Saskia]

holy fuck. The Galep-5 went for just 75 effing Euros less than it costs new, and it was missing all its accessories.
Are people just plain stoopeed ?

[bd139]

Yes

[Saskia]

I think I now must bid on this HP48G just out of spite and disdain.

[Ice-Tea]

We need proof. Send more photos.    

Next time something blows up, I will. I doubt the wait will be long. Lots of gear inbound.

[GreyWoolfe]

CPAP machine anyone?

My neighbor got a new CPAP (continuous positive airway pressure) machine and the supplier said to throw this one away. He asked me if I wanted to play around with the old one (he knows me pretty well). Of course I do. It's a ResMed unit and the PCB says Sydney, Australia.

So what it does is give you positive air pressure in your airway all night. It has a control unit which has an SD card. The SD card appeared to have daily files on it giving the prescriber the data on the performance. In the control unit is a blower. The left side connects to the right side which has a water reservoir for humidity control. Then the air comes out a long tube to your mask.

The main unit has a menu system for some simple user settings, but there is no way to control the air pressure in the menu. He said they can do it in the office if needed after a sleep study. There is an interface connector on the back but not one I recognize. I presume that is where they connect an external computer or proprietary unit to set it up.

Some of the parts used, other than the usual suspects such as voltage regulators and the like -

stm32f103zgt6
ARM® Cortex®-M3 STM32F1 Microcontroller IC 32-Bit 72MHz 1MB (1M x FLASH

Sensiron sdp711-01 differential pressure sensor

GE NPA-C02035 Surface-Mount Pressure Sensor

On the top side of the PCB are a whole lot of gold pads, perhaps for testing? In the water reservoir unit is a humidity sensor that sends it's data back through the interconnect between units.

Right now it blows a steady stream of air and doesn't require the humidity unit to run. Might be useful for a project someday. 

I have a Phillips Respironics CPAP myself.  For me, heated humidity is an absolute must.  Otherwise, my nose and throat dries out and is very uncomfortable.  Mine also has a heated hose to keep moisture from accumulating in the hose, causing gurgling sounds.  Very annoying for both Mrs GreyWoolfe and I since I have difficulty falling asleep normally.  Thankfully I don't stop breathing multiple time a night. Mine is also an AutoPAP.  It is programmed with a low and high pressure range and it sets the pressure based on breathing patterns.  It also eases the pressure on exhale so the lungs don't work as hard.  For me, it literally is a life saver.  I keep a spare older model in the closet as a back up just in cases but the current unit is just over a year old, so should be good for some time yet.  Not all units are unhackable.  Both that I have can be user adjusted.  There is documentation on the net on how to do it.  The Doctors don't want you knowing it so you have to pay them money for visits/sleep studies.  Having the ability to hack the unit kept me from blowing cash on another Dr visit/sleep study to get a  script from the neurologist to replace the unit that failed.

[nixiefreqq]

real men have wood.

this was the calculator my old man used in college.

so it is circa 1948.

[bd139]

Dogs looking like "so when the hell are you going to stop posing with your phone and throw the stick?"