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968.911
07-24-02, 10:39 AM
Curiosity got the better of me...

I took the cover off to check out the guts of the 721. The attached picture shows the 721, a close-up of the Broadcom 7021 video/mpeg processor, the National Geode CPU (I think thats what it is under the heat sink), and the Connexant tuners on the tuner blades.

Notice the pci style connector to the left of the processor? Ethernet card anyone? How about video sharing like Replay TV?

The power supply (left of the pci connector) is absolutely huge? The power supply generates most of the heat in the system. Hard drive is probably the second largest heat source.

The fan is under the hard drive (under the bracket on the right side of the tuner blades). It does not move much air.

I installed a second plastic squirrel cage fan that fit below the tuner blades and to the left of the hard drive. It draws air from underneath the hard drive, through the original fan and blows it across the motherboard, through the power supply and out the vents on the left side.

The system is now cool to slightly warm to the touch. It was burning hot to the touch before the mod. The fans now turn off after running for about 5-10 minuts and seem to come on ever hour or so. With the system "powered off" the fans have not come on yet (overnight).

The fan noise was driving me nuts. Now, I love this thing. Best piece of hardware out of Echostar to date. Keep it coming!!!

I want software updates. Make it like Tivo... PLEASE!!!

SParker
07-24-02, 11:00 AM
Thanks for making the sacrifice so all of us can see the internal workings! It looks awesome!!

Scott Greczkowski
07-24-02, 11:01 AM
Metro25 showed me some pics from inside the 721 last week.

Good pictures, the picture of the PCI slot is suprising. :) I don't think it will ever be for consumer use, as I don't think that they want everyone opening the cover of the 721 to put a card in.

I am kind of suprised they don't put tamper switches in their PVR units to prevent folks from tinkering in the units. :)

SParker
07-24-02, 11:11 AM
Mine will never be opened unless it is by Dish Network I don't want to void my warranty. So the HD is at the front of the unit?

jerryyyyy
07-24-02, 12:27 PM
Could you explain a bit more about how you put in the fan and a better description of the fan itself- whereyou got it and maybe a photo?. I assume you wired it onto the connections for the other fan so it would shut on and off as well?

The warranty will be gone in a year anyhow and by then it may be fried without good cooling.

I have not examined it well myself but I think that there in now way for air to enter the unit from the right side to blow out the left side. We have SGI computers in our lab that do this and act like small vaccum cleaners- stay cool but have to watch the filers.

marshalk
07-24-02, 12:36 PM
I wonder if one could figure out a way to output to vga/xga. That would be bad to the bone. I use a large 16:9 RP monitor (a sony) that has video, svideo and rgb. I use a skyworth dvd that has rgb output and the image is stunning. I would love to have the 721 output in vga but I realize that is probably wishful thinking. I will probably do the fan mod if 968 woudl be good enough to provide some pix and direction.

SParker
07-24-02, 12:37 PM
I have Dish's extended warranty so it will go beyond a year on mine most likely.

968.911
07-24-02, 01:13 PM
The fan is a PC fan. Its the type that plugs into a PCI card slot (no actual edge connector). It sucks air from the side and blows out the back.

Its called a 'slot' cooler fan.

I took off the metal bracket and installed the fan with the exhaust pointed to the left (at the power supply when looking down on the 721 unit with its front towards you).

The fan fits perfectly between the front of the unit and the two tuners. I zip-tied it to the plastic post between the tuners. I'll do a better mounting job once I am convinced that this works.

In this arrangement, the fan intake is on the bottom and exhaust to the left.

I connected it in parallel with the existing fan.

So air is being sucked in from the bottom (original fan opening)and possibly behid the unit.

One note: I have a 501 that has been running HOT for the past year. The fan has always been on, and the case is HOT to the touch. No problems with functionality. Its noise did not bother me since its running the TV in the den. I ended up moving this up to the top shelf of the entertainment unit, and its fan is now turning off when the 501 is powered off.

Here is a picture of the fan I used...

http://www.hobbytron.net/media/slf-01.jpg

Another picture if the above does not work...

http://www.mikhailtech.com/articles/cooling/pciroundup/pciroundup-logo.gif

MrAkai
07-24-02, 04:38 PM
Looks like it might be an AGP slot. anyone daring enough to plug a video card into it? :)

jerryyyyy
07-24-02, 05:06 PM
This looks like one for $5?

http://www.pcbay.net/coolfanforsy.html

This looks like yours for $14:

http://www.cablesnmor.com/fan-card.html

Was it hard to take the case off? Zip tie sounds simple (permanent by my standards). Constant fan drives me wild too.

JohnnyConfidence
07-24-02, 05:06 PM
The pictures are great. Anyone know a place to find some documentation on the hardware and what can be done with it. I know there are lots of docs out there for Tivo's and such that let you upgrade drives and things of that sort. Does anyone know what OS this thing runs, how the drives are setup those sorts of ideas? I'm ready to chop this thing up, warrenty be damned :D

KhakiBoy
07-24-02, 09:29 PM
I'm thinking AGP slot too, judging from the dark brown color. Wish I had one of these bad boys. I'd love to pop a vid card in and see what happens.

Bill D
07-24-02, 09:51 PM
I just purchased but have not installed a small DC voltage fan, that I was going to mount in the back of my entertainment closet. I am really not up for cracking the 721 open to do the fan install there. On the back wall of my cabinet I was going to add the fan, should I cheat it towards one side or the other. I was going to put it near back right side, since the front left seems to be the hottest. Also I was going to exhaust outward, there is a few inches between the cabinet and the drywall.
any comments or suggestions on this setup..
This is the fan I just ordered
http://www.pcpowercooling.com/products/alarmandaccesories/silencerfan/index.htm
thanks

Sherlock
07-24-02, 11:44 PM
Originally posted by KhakiBoy
I'm thinking AGP slot too, judging from the dark brown color. Wish I had one of these bad boys. I'd love to pop a vid card in and see what happens. Good luck with the driver!:D

rbird
07-25-02, 05:18 AM
That's the beauty of Linux...there may be a driver already available. :)

Still the Linux kernel would have to be told to look for it. THAT'S the kicker. Unless E* has released their kernel source (which they should be required to do under the GPL).

Not sure why you'd want a graphics card in the 721 anyway. Do you REALLY want to blow up an E* signal to computer monitor resolutions? :D

Bob

Neil Derryberry
07-25-02, 06:48 AM
AGP slots are smaller than pCI.... and that definitely looked like pci.

Forget the video... what about plugging in a firewire card...?!!!

P Smith
07-25-02, 01:54 PM
968.911

can you please make a picture of bottom side main PCB ?
or may be some macroshots from top where is a "JTAG" letters persist ?

what is main CPU type ?

P Smith
07-25-02, 01:56 PM
Originally posted by Neil Derryberry
AGP slots are smaller than pCI.... and that definitely looked like pci.

Forget the video... what about plugging in a firewire card...?!!!

this slot looks familiar for me - it shoud be VESA type - High Speed Extention Slot ...

968.911
07-25-02, 02:30 PM
Getting pix from the bottom side of the board would not be easy. I don't want to take anything more than the case apart.

The processor is a National Semiconductor Geode GX1. (http://www.national.com/news/item/0,1735,720,00.html).

JTAG? hmmmm... :bang: :crying:

kyoo
07-25-02, 03:09 PM
VESA type? as in VESA Local Bus? I have a VLB video card in my junk pile somewhere..

Can anyone confirm the slot type?

Perhaps it's time to break my 721...

Mike123abc
07-25-02, 05:55 PM
I wonder what features are planned for that slot.... Maybe a future 8PSK upgrade or conversion to the new platform after the merger. Probably would have to take your box to a dealer to have them pop in a new card.

If they were thinking hard when they designed this box they probably would want to make it merger upgradable proof and maybe 8PSKable if they decide to move more than just HDTV to 8PSK.

Kagato
07-25-02, 06:30 PM
It could be a lot of things. Just because it fits a certain form factor doesn't mean it's going to be what you think it is. Example, the edge connector on the STB Tivo fits a PCI bus form factor, but it's not a PCI bus.

Here's my guess. And it's just a guess. From what I see you have a pair of tuner card that most likely are self contained STBs for the most part. It's all very modular. I think the slot is most likely PCI. I think it's a modular design that would allow the 721 to become a 921 by simply adding a card with a HD chipset and updating the software and chasis. There is a lot of economy you can get between the two models if you reuse 80% of the parts.

One of the chips in your pic appears to be a broadcom product. Most likely the MPEG decoder (BCM7040 or BCM7041).
Broadcom makes 4 HD chips now. Two are PCI based.

968.911
07-26-02, 09:25 AM
The Broadcom product is a BCM7021. This has PCI and it can do HD resolutions. (http://www.broadcom.com/products/7021.html)

The PCI'ish bus is most likely for things like terrestrial HD tuner or component video out (whats the use of HD without component or digital out?). Actually, this connector could support just about anything. (wireless lan, sattelite upstream?)

By the way, the 7021 can to HD and standard definition outputs simultaneously. Possibly you can connect two monitors in the future? or PIP with HD/Standard mixed?

One other cool piece of info. Future boxes sound like might have the feature where it only requires one cable to run in the house and serve multiple receivers. Its most likely going to need a new switchbox at the dish(es).

P Smith
07-26-02, 09:48 AM
968.911,

yes, the processor have JTAG signal pins - so, could you please make close look into the IRD for discover pad/pins with words : JTAG, TCK, TMS, TDI, TDO, TRST ? and make a micro picture ?

I wrote VESA _TYPE_ connector - nothing here related to VESA bus itself .
More, I was point to HSEP - look likes nobody knows that .

SParker
07-26-02, 10:11 AM
so this might be able to do HD in the future?

P Smith
07-26-02, 12:34 PM
may be ... it's will be 921 unit ...

Mike123abc
07-26-02, 03:11 PM
Has anyone found out if they are using the broadcom 8PSK chip set too in the 721? This would be a big clue if they were planning to use a common platform for the 721/921.

The 8PSK chipset that they now have in the 6000 does QPSK (all but the new HDTV channels) 8PSK (the new HDTV) and 16QAM the next step above 8PSK.

I would hope that they would put the new chipset in all new reciever designs. Maybe, just maybe someday they could decide that everyone should have the new chipsets or it become econimically feasable to upgrade the last holdouts.

Dmitriy
07-26-02, 03:16 PM
Originally posted by P Smith
may be ... it's will be 921 unit ...

You mean same case? Maybe....:rolleyes:

Actually 921 will probably look like this http://www.dishretailer.com/ts2002/Disk3/MVC-014S.JPG

Kagato
07-26-02, 04:31 PM
The single box for mutliple TV's in an interesting idea, but you'd still need 4 runs to cover all the LNBF combos. (Or 6 for us 61/148 users).

Looking at the chipset it appears to be able to handle 2 SD channels to do all the fun PIP stuff. However, it's limited to a single display when dealing with HD content, (i.e. no PIP). But like 968.911 said, it will output both HD and a scaled SD at the same time. Which is more than you can say for the 6000.

Furthermore the chipset does all the PVR fuctions as well. Including scheduling. This might explain all the funky promblems myself and others had the first couple days of use as it appeared the guide (most likely in Linux) was in sync, but the scheduler was not.

A little bit of a let down is the fact that the chip set is nice enough to encypt the PVR content with 3DES. Soooo, Dish most likely didn't have to go through half the R&D Tivo went through to create their own MFS filesystem to keep the the content locked up. You might even be able to mount the HD with little or no modification because they don't have to care.

I don't see anything about it being able to decode anything other than ATSC though. So my guess is for this to become a 921 you'd need to mod the board or put in a serious daughter card. From the look of Dmitriy's picture it looks like the 921 on display has a similar form factor, but is taller to fit extra "stuff" in.

P Smith
08-01-02, 10:10 AM
I mean handle HD signal for PVR features ... size ? who cares ?

jd1866
08-10-02, 12:36 PM
Can someone take a picture of the JTAG port on the 721? I would like to take a look at it. Also could someone take a pic of the TSOP and EEPROM chips on the receiver? It would be much appreciated!

P Smith
08-10-02, 01:03 PM
jdk ? no one know what are you talking about here ...