Using USB Hub WARNING

[MarsG76]

Hello astronomers,

If any of you are using a lot of USB Devices on a laptop through a USB hub make sure you're using a power supply on it....

I set up two of my old laptops, a HP 17" LCD Pentium 4 WinXP (Very nice screen, best I've seen on any laptop to date) and a SONY 13" VAIO Core2Duo WinVista Laptops, 1TB SSD. The HP is about 15/16 Years old and the Sony is about 9/10... I hooked up the Celestron handcontroller, IS DMK21au618, GP USB autoguider and the Canon 40D to a hub and the hub, first, to the HP Laptop... Soon after, two or three days later, the HP laptop developed some squiggly green lines through it, I changed the res/the features, the refresh, shut down/reboot, etc, but the problem persisted.. might have boot up clean, but soon the same grees lines/squiggles returned, sometimes the lines are on the POST (BIOS) screen... obviously this is a video chip issue.

Due to the age of the laptop, I figured that happened because it's old and it was it's time... although it still worked otherwise and was still usable...

This was until I hooked up the hub to the Sony VAIO and during a autoguiding session the Sony froze with vertical lines through the display... when I powered down and attempted to boot up the sony, it always presented me with the BSOD.. that is during a boot repair, safe mode and attempted reinstall of the OS, all ended with a BSOD. There are vertical lines always during the boot up, on the POST (BIOS) screen, so again it is, potentially, a video chip issue.

The thing is that this happened days apart, so I automatically suspected one of two things:

One is that they're two old laptops, so there is a possibility that this was a coincidence....

BUT I'm steering more strongly to the fact that perhaps the units attached to the USB port drew too much power, caused some kind of surge/spike and the video chip was the weakest link in both situations... I thought that perhaps the power supply on the hub was not capable of outputting enough current/power, but on a closer inspection it turned out that the hub power was not turned on, otherwise it's powered by a 5.5V 2000mA power pack.

Perhaps a combination of both, surge+ old age....

 

Remember to power your USB Hubs and potentially save yourself some cash, but more importantly time re setting up a new computer for your astro work.

 

I scored a 16" Sony VAIO laptop on ebay and won it for $28!!! and I can't fault it... so WIN WIN... this is the replacement for the observatory.

Hopefully the hub not being powered and power hungry combination or peripherals is what caused the problem and I don't lose a third laptop...

 

Clear skies, and screens...

 

 

 

 

[MarsG76]

I connected the Canon 7D to APT along with the DMK21 and also the autoguider and hand controller were connected too, through the hub that was powered 5.5V/2000mA... setup for my next image... 

After playing with it and the OAG trying to find a guide star for about a hour, there were no problems with the laptop... hopefully none will materialize and the unpowered hub theory is what killed both of my laptops.

[IanL]

Erm, nope. That's not how USB power works.

The laptop to hub connection will be able to supply a maximum current. The hub can't draw more than that and nor can the downstream devices.

If there is insufficient power, one or all of the downstream devices will not work or will only work intermittently.

Ageing laptops being used outside in the cold and damp is more likely the cause.

[MarsG76]

14 minutes ago, IanL said:

Erm, nope. That's not how USB power works.

The laptop to hub connection will be able to supply a maximum current. The hub can't draw more than that and nor can the downstream devices.

If there is insufficient power, one or all of the downstream devices will not work or will only work intermittently.

Ageing laptops being used outside in the cold and damp is more likely the cause.

I know the theory behind how USB is meant to work, but two different age and brand laptops with different hardware powered by different power supplies but same damage is very sus.

Some old pre 2005 laptops apparently didn't have over draw protection on USB either so if that happens to the current laptop, again a video problem, than I'll start to suspect a possible short in one of the USB cables... than again the current laptop is more recent so maybe it'll be protected.

If it does fail again than I'll get a brand new laptop for the obsy and it'll be covered by warranty.

 

 

[alexbb]

Now if only I could find my USB 3.0 hub... good thing is that you can use a power bank to power the hub. A large 15600mAh one kept my hub powered on many nights on a single charge.

[MarsG76]

11 minutes ago, moise212 said:

Now if only I could find my USB 3.0 hub... good thing is that you can use a power bank to power the hub. A large 15600mAh one kept my hub powered on many nights on a single charge.

At 15.6A I'm surprised it didn't keep it powered up for a month...

[Juicy6]

Why? Assuming the USB devices together draw 1,5 A from the battery, 15,6 Ah will last for 15,6/1,5 hours, or about 10 hours. Probably voltage will be too low already after maybe 6-8 hours.

[MarsG76]

23 minutes ago, Juicy6 said:

Why? Assuming the USB devices together draw 1,5 A from the battery, 15,6 Ah will last for 15,6/1,5 hours, or about 10 hours. Probably voltage will be too low already after maybe 6-8 hours.

It was a gag, referencing the 15600mA battery level... in reference that most common batteries are 4700mA or 6800mA.

 

[alexbb]

My camera is also powered and has an USB 2.0 hub by itself. The guiding camera and the filterwheel are connected to the imaging camera. They should draw minimum power from the USB, I don't want to draw anything from my mini-PC. It actually could be possible to last a month like this

Anyways, I didn't encounter any issues when I connected all the stuff to my laptop's USB 3.0 port without any hub. I use the hub when I connect any device to my upboard since this requires 4A with the USBs, but I only power it with just above 2A. In theory, you should not have any issues with USB 3.0 on the host machine.

[MarsG76]

14 hours ago, moise212 said:

My camera is also powered and has an USB 2.0 hub by itself. The guiding camera and the filterwheel are connected to the imaging camera. They should draw minimum power from the USB, I don't want to draw anything from my mini-PC. It actually could be possible to last a month like this

Anyways, I didn't encounter any issues when I connected all the stuff to my laptop's USB 3.0 port without any hub. I use the hub when I connect any device to my upboard since this requires 4A with the USBs, but I only power it with just above 2A. In theory, you should not have any issues with USB 3.0 on the host machine.

In theory it all should work. It the way I see it is I already lost two laptops and the equipment used for Astro is not brand new, so as stated above the age of the laptops might be a factor... I'd rather play it safe, take too long to setup a replacement laptop with all of the software and drivers.

The aren't in the open, not at the mercy of the environment but have a corner in the obsy where they are not exposed to any moisture, so that should take the edge off the electronics while imaging.

[skybadger]

I have 3 quad USB cards in the obbo PC as well as the motherboard connectors. So my worry is not that a single connection will draw too much but that the sum of the connections will overwhelm the psu.

 

[MarsG76]

21 hours ago, skybadger said:

I have 3 quad USB cards in the obbo PC as well as the motherboard connectors. So my worry is not that a single connection will draw too much but that the sum of the connections will overwhelm the psu.

 

Now that is a lot of juice for astro gear...What exactly do you connect to need that much power?

 

[skybadger]

Serial hub

USB hub at scope

Game controller

Sx camera

Zwo camera

Nikon video in

Nikon control out

Dome remote serial/wireless

Couple of spare cables for other kit...

It's not really about power, since few items consume that much, it's about those items that take a lot of bandwidth and don't work together through hubs but do work connected directly..

M

 

[MarsG76]

10 minutes ago, skybadger said:

Serial hub

USB hub at scope

Game controller

Sx camera

Zwo camera

Nikon video in

Nikon control out

Dome remote serial/wireless

Couple of spare cables for other kit...

It's not really about power, since few items consume that much, it's about those items that take a lot of bandwidth and don't work together through hubs but do work connected directly..

M

 

Now thats a installation.....

I agree about the bandwidth... I find that when capturing planets at 60fps, I'm better off connecting the DMK21au618 directly, since through the hub with other peripherals I get a lot of black frames.