Author Topic: What did you buy today? Post your latest purchase!  (Read 1349840 times)

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Online McBryce

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Re: What did you buy today? Post your latest purchase!
« Reply #5025 on: December 12, 2017, 07:40:15 am »
Those Amazon $10/4-pack DC/DC modules are actually quite efficient -- they run very cold, not even warm to touch, while stepping down 19V to 12V, ~1.5A, without any thermal solution, wrapped in electrical tape.

It would be the EMC they're spewing out into the computer case that would worry me more than thermal issues.

McBryce.
 

Offline blueskull

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Re: What did you buy today? Post your latest purchase!
« Reply #5026 on: December 12, 2017, 07:49:09 am »
Those Amazon $10/4-pack DC/DC modules are actually quite efficient -- they run very cold, not even warm to touch, while stepping down 19V to 12V, ~1.5A, without any thermal solution, wrapped in electrical tape.

It would be the EMC they're spewing out into the computer case that would worry me more than thermal issues.

McBryce.

Conductive noise is taken care of by CM ferrite beads.
 

Offline Specmaster

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Re: What did you buy today? Post your latest purchase!
« Reply #5027 on: December 12, 2017, 09:33:33 am »
Bad news. My previous RX 560 purchase was proven to be wrong. My old R9 nano is not faulty, and the fault was a WiFi card shipped with my motherboard. 15% restocking fee down the drain.

Lesson learned: never buy cheap motherboards from AsRock. I knew $200 for an X99 mobo with WiFi and USB3.1 can't be good, but anyway. It's indeed very stupid to put a $200 mobo in a multi-thousand-dollar dream setup.

Arrived today is a Mediasonic external HDD raid box which I'm using in my NAS setup. I no longer want my HDDs to be in my main computer chassis, so I need to find a place to plug them into.

I did 2 modifications on the enclosure, first by adding a DC/DC module in fan cable to step down the noise, then by adding another DC/DC module to convert 19V to 12V, so I can tap power from my Intel NUC power brick to power my HDD enclosure. The NUC PSU is a 65W unit, and the NUC will never suck more than 25W from it.

Those Amazon $10/4-pack DC/DC modules are actually quite efficient -- they run very cold, not even warm to touch, while stepping down 19V to 12V, ~1.5A, without any thermal solution, wrapped in electrical tape.
I've had a few motherboards from Asrock in the past and they've been OK.
Who let Murphy in?
 

Offline blueskull

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Re: What did you buy today? Post your latest purchase!
« Reply #5028 on: December 12, 2017, 09:49:48 am »
I've had a few motherboards from Asrock in the past and they've been OK.

My AsRock X99E-ITX/ac had problems since day 1. At first, it refused to boot OEM-only E5v3 CPU (E5 2696v3), while MSI and Asus boards both boot them well. Then after a BIOS update and this issue fixed, it starts to BSOD, again, BIOS issue, solved by painstakingly waiting for new BIOS update. During this time, it experienced various problems, mainly Win7 compatibility issues (X99 is supposed to support Win7, but mine had all sorts of bizarre USB issues). It also had WiFi and USB3.1 issues. Since both USB3.1 and WiFi are connected via PCH PCIe, I don't know if PCH PCIe is f*ed, but hay, I don't use them anyway.

It also has this RAM compatibility issue. I know I was not using a qualified RAM stick, I was using a sever-only, not officially supported RAM, but the Xeon CPU on an Asus/MSI/GB X99 can boot with that RAM perfectly. I had to swap the RAM for another non supported server RAM, this time my guesswork worked.

Moving on, a year later (which is just few days ago), its broken WiFi started to prevent system form cold boot in a cold day, I guess it's some sort of PCH PCIe-related balls crack, but my solution is to just remove WiFi card and disable USB3.1 in BIOS and hope this problem will never be triggered again. My SSD and GPU are all hooked up to CPU PCIe lanes directly, so I don't need even a single PCH PCIe lane.

So maybe if you use all qualified parts, then an AsRock will do, but for people like me who use highly experimental component combinations, maybe a more compatible mobo is better.

Still amazingly, almost all my computer parts are not officially natively supported.

CPU: E5 2696v4 (previously 2696v3), OEM-only SKU, not officially supported by any mobo
RAM: Micron server LRDIMM, not supported by X99, but supported by C612 (same silicon as X99, different configuration bits)
SSD: Intel 750 (officially supported by X99 after successive BIOS update, released after initial debut of X99)
CPU cooler: incompatible with AsRock's special narrow ILM, had to be mechanically modded
USB3.1: AsMedia first gen 3.1 chip with more silicon bugs than STM32

I probably should be glad that with all those non compatible things combined, I can still type on this computer.
 

Offline Decoman

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Re: What did you buy today? Post your latest purchase!
« Reply #5029 on: December 12, 2017, 12:14:28 pm »
Hakko 633-01 Soldering iron holder

Being a newbie to soldering, I am confused as I find so called "brass" products for cleaning soldering irons, but then later down the page I see the same product being described as "gold" "color" "steel". Looking for a tumbled brass ball, I am having difficulty finding it on eBay. Update: Ok, I finally found a sales listing that at least clearly promises brass, and not steel.
« Last Edit: December 12, 2017, 12:34:00 pm by Decoman »
 

Offline edgelog

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Re: What did you buy today? Post your latest purchase!
« Reply #5030 on: December 12, 2017, 09:38:37 pm »
An adjustable isolation transformer. Seems to consist mainly of two regular transformers and a toroid variable transformer. I haven't figured out how they make this work, though. Anyone knows? The beast weights 25 kg, BTW.

 

Offline Free_WiFi

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Offline Mr. Scram

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Re: What did you buy today? Post your latest purchase!
« Reply #5032 on: December 12, 2017, 09:44:23 pm »
Bad news. My previous RX 560 purchase was proven to be wrong. My old R9 nano is not faulty, and the fault was a WiFi card shipped with my motherboard. 15% restocking fee down the drain.

Lesson learned: never buy cheap motherboards from AsRock. I knew $200 for an X99 mobo with WiFi and USB3.1 can't be good, but anyway. It's indeed very stupid to put a $200 mobo in a multi-thousand-dollar dream setup.

Arrived today is a Mediasonic external HDD raid box which I'm using in my NAS setup. I no longer want my HDDs to be in my main computer chassis, so I need to find a place to plug them into.

I did 2 modifications on the enclosure, first by adding a DC/DC module in fan cable to step down the noise, then by adding another DC/DC module to convert 19V to 12V, so I can tap power from my Intel NUC power brick to power my HDD enclosure. The NUC PSU is a 65W unit, and the NUC will never suck more than 25W from it.

Those Amazon $10/4-pack DC/DC modules are actually quite efficient -- they run very cold, not even warm to touch, while stepping down 19V to 12V, ~1.5A, without any thermal solution, wrapped in electrical tape.
Expensive motherboards aren't any better. I've seen people having huge issues with Asus, Gigabyte, Intel and other motherboards. If you get a bad hand, you get a bad hand.

A lot of people seem to be using Asrock motherboards with few issues, so YMMV.
 

Offline bitseeker

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Re: What did you buy today? Post your latest purchase!
« Reply #5033 on: December 12, 2017, 09:52:26 pm »
An adjustable isolation transformer. Seems to consist mainly of two regular transformers and a toroid variable transformer. I haven't figured out how they make this work, though. Anyone knows? The beast weights 25 kg, BTW.

The two regular transformers are probably back-to-back to end up with 1:1 turn ratio. I'm not sure why they didn't just do that with a single 1:1 transformer. Perhaps to be able to change the input voltage and/or range.

The auto-transformer (a.k.a., Variac) provides the adjustable output voltage. The front panel knob appears to be attached to the auto-transformer shaft, but it could also go to a pot or rotary encoder and use a servo or similar mechanism to enable electronic control.

Kerry Wong did a video on a voltage stabilizer that used a servo-controlled auto-transformer to control the output.
I TEA.
 

Offline tooki

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Re: What did you buy today? Post your latest purchase!
« Reply #5034 on: December 12, 2017, 09:53:10 pm »
My latest purchase, if you will, is about $2500 of tattoo work. So much left to go... ::sigh::
 

Offline edgelog

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Re: What did you buy today? Post your latest purchase!
« Reply #5035 on: December 12, 2017, 09:57:30 pm »
The two regular transformers are probably back-to-back to end up with 1:1 turn ratio. I'm not sure why they didn't just do that with a single 1:1 transformer. Perhaps to be able to change the input voltage and/or range.

That makes sense.

The auto-transformer (a.k.a., Variac) provides the adjustable output voltage. The front panel knob appears to be attached to the auto-transformer shaft, but it could also go to a pot or rotary encoder and use a servo or similar mechanism to enable electronic control.

The knob is physically connected to the shaft, adjusting the position of the roller tap. There's no servo in this device.
 

Offline Mr. Scram

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Re: What did you buy today? Post your latest purchase!
« Reply #5036 on: December 12, 2017, 10:00:42 pm »
My latest purchase, if you will, is about $2500 of tattoo work. So much left to go... ::sigh::
I'd be willing to stab you for half of that. PM me for details.  >:D
 

Offline Macbeth

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Re: What did you buy today? Post your latest purchase!
« Reply #5037 on: December 12, 2017, 11:27:10 pm »
Quote from: edgelog
The two regular transformers are probably back-to-back to end up with 1:1 turn ratio. I'm not sure why they didn't just do that with a single 1:1 transformer. Perhaps to be able to change the input voltage and/or range.

That makes sense.
Quote from: tooki
My latest purchase, if you will, is about $2500 of tattoo work. So much left to go... ::sigh::

That makes no sense whatsoever.  :palm:
 

Offline Specmaster

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Re: What did you buy today? Post your latest purchase!
« Reply #5038 on: December 12, 2017, 11:38:36 pm »
The two regular transformers are probably back-to-back to end up with 1:1 turn ratio. I'm not sure why they didn't just do that with a single 1:1 transformer. Perhaps to be able to change the input voltage and/or range.

That makes sense.

The auto-transformer (a.k.a., Variac) provides the adjustable output voltage. The front panel knob appears to be attached to the auto-transformer shaft, but it could also go to a pot or rotary encoder and use a servo or similar mechanism to enable electronic control.

The knob is physically connected to the shaft, adjusting the position of the roller tap. There's no servo in this device.
It could also be that transformer 1 is a step down transformer feeding a small low voltage variac which then feeds into a low voltage primary on transformer 2 which is a step transformer. This way round I think that they will require a far smaller physical size of variac to help keep the overall size of the unit down?
Who let Murphy in?
 

Offline Cubdriver

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Re: What did you buy today? Post your latest purchase!
« Reply #5039 on: December 12, 2017, 11:44:27 pm »
The two regular transformers are probably back-to-back to end up with 1:1 turn ratio. I'm not sure why they didn't just do that with a single 1:1 transformer. Perhaps to be able to change the input voltage and/or range.

That makes sense.

The auto-transformer (a.k.a., Variac) provides the adjustable output voltage. The front panel knob appears to be attached to the auto-transformer shaft, but it could also go to a pot or rotary encoder and use a servo or similar mechanism to enable electronic control.

The knob is physically connected to the shaft, adjusting the position of the roller tap. There's no servo in this device.
It could also be that transformer 1 is a step down transformer feeding a small low voltage variac which then feeds into a low voltage primary on transformer 2 which is a step transformer. This way round I think that they will require a far smaller physical size of variac to help keep the overall size of the unit down?

If anything, at a lower voltage you'd probably need a bigger, heavier variac - remember, as voltage goes down, current goes up for a given power.

-Pat
If it jams, force it.  If it breaks, you needed a new one anyway...
 

Offline Specmaster

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Re: What did you buy today? Post your latest purchase!
« Reply #5040 on: December 12, 2017, 11:49:37 pm »
That is correct but you would also need fewer windings as well surely?
Who let Murphy in?
 

Offline bitseeker

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Re: What did you buy today? Post your latest purchase!
« Reply #5041 on: December 13, 2017, 01:15:15 am »
The auto-transformer (a.k.a., Variac) provides the adjustable output voltage. The front panel knob appears to be attached to the auto-transformer shaft, but it could also go to a pot or rotary encoder and use a servo or similar mechanism to enable electronic control.

The knob is physically connected to the shaft, adjusting the position of the roller tap. There's no servo in this device.

OK. That works fine and is certainly simpler having the knob just turn the variac. With the digital displays, I just couldn't tell how far they went with digital-ness.
I TEA.
 

Online BU508A

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Offline blueskull

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Re: What did you buy today? Post your latest purchase!
« Reply #5043 on: December 13, 2017, 07:13:17 am »
I bought for my self this awesome set of screwdrivers!!!
https://www.banggood.com/XIAOMI-Wiha-25-in-1-Screwdrivers-Kits-With-24pcs-S2-Steel-Screw-Bits-and-Aluminium-Alloy-Screwdriver-p-1187158.html

The genuine ones can be found here:
https://www.wiha.com/

The Xiaomi one is a collaboration between Xiaomi and Wiha, it's basically made in China under Wiha's license and Xiaomi's branding.
The handle and case are definitely made by Xiaomi or its OEMs, the tips are likely to be made by Wiha. I have a set of these.
 

Online BU508A

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Re: What did you buy today? Post your latest purchase!
« Reply #5044 on: December 13, 2017, 07:28:34 am »
The Xiaomi one is a collaboration between Xiaomi and Wiha, it's basically made in China under Wiha's license and Xiaomi's branding.
The handle and case are definitely made by Xiaomi or its OEMs, the tips are likely to be made by Wiha. I have a set of these.

I've bought one set and will check it out.
“Chaos is found in greatest abundance wherever order is being sought. It always defeats order, because it is better organized.”            - Terry Pratchett -
 

Offline blueskull

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Re: What did you buy today? Post your latest purchase!
« Reply #5045 on: December 13, 2017, 07:33:09 am »
The Xiaomi one is a collaboration between Xiaomi and Wiha, it's basically made in China under Wiha's license and Xiaomi's branding.
The handle and case are definitely made by Xiaomi or its OEMs, the tips are likely to be made by Wiha. I have a set of these.

I've bought one set and will check it out.

FYI, https://www.wiha.com/en/press-reports/detail/wiha-proud-of-co-branding-partnership-with-chinese-smartphone-manufacturer-xiaomi/
 
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Offline neo

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Re: What did you buy today? Post your latest purchase!
« Reply #5046 on: December 13, 2017, 07:47:38 am »
Blueskull, i just plugged my headphones into my sony amp and turned it all the way up, way past anything i would ever play through.

You were right there is alot of noise actually, high pitched squealing and digital static. Though below volume level 28/75, a sane listening volume, it is inaudible.
A hopeless addict (and slave) to TEA and a firm believer that high frequency is little more than modern hoodoo.
 

Offline Decoman

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Re: What did you buy today? Post your latest purchase!
« Reply #5047 on: December 13, 2017, 10:26:51 am »
Being new to soldering, and having to wait for stuff to arrive in the mail, I decided to get four more soldering tips in addition to the one that came with the soldering station I also ordered somewhere on eBay:

As I understand it, the flat ones will transfer more heat over to a flat surface. And I will have to guess that the thin and curved one is for soldering tiny spots that maybe are hard to get at.

Edit: Unsurprisingly, I have a lot to learn about soldering. :)

« Last Edit: December 14, 2017, 07:15:37 pm by Decoman »
 

Online McBryce

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Re: What did you buy today? Post your latest purchase!
« Reply #5048 on: December 13, 2017, 02:10:38 pm »
The fourth one you've circled isn't really for soldering. These are usually used for modelling plastics or woodwork. The first and third you've marked will cover you for 95% of what you want to do.

McBryce.
 

Offline rdl

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Re: What did you buy today? Post your latest purchase!
« Reply #5049 on: December 13, 2017, 02:47:14 pm »
Yep, I got my first good soldering iron in 2004. It was a Hakko 937 and came with the usual pointed conical tip. I replaced that tip with one that looks like the first on the left in your picture and that's been just about all I've ever used.
 


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