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Bill Mullin
06-04-03, 10:38 AM
I spent a LOT of time on the phone with Dish advanced support working on the pixelation and sound dropout problem, and a LOT of time on my own before resolving the problems on my 721. In retrospect, 90% of this effort was because the problem was intermittent. Had there been continual problems, the situation would have been cleared up weeks ago.

Background: I got my 721 in August, 2002, at which time it worked perfectly. In December, I left town for a week, but before leaving I programmed the 721 to record 14 movies. When I returned, all 14 had been recorded and all were flawless ~ I was a happy camper! In January, just about the time software version 109 was released, I started seeing pixelation and sound dropouts in my recordings. I also had "acquiring tuner" messages, but these were rare. Since the new software version had just come out, of course software was suspect, but in my case this turned out not to be the cause of the problem.

Last week I decided to simply sit in front of the TV for as long as it took and watch for the pixelation to start up. Whenever it did, I performed tests. Needless to say, I wasted a lot of time watching clean video between short bursts of pixelation. Here's some of the things you can do to pinpoint and cure the problem:

(Print out the caveat and #1 - #9, then have the printout beside you as you work on your problem.)

Lawyer caveat: Note that you're performing the following tests at your own risk!

1. There are 5 different areas where pixelation can occur. These areas are the LNBF, the coax between the LNBF and the grounding block (GND), the GND itself, the coax between the GND and the 721, and the 721 itself. The following tests will help you isolate where the problems originate. Of course once you have identified the source of the problem, the fix will be easy.

2. On the back of the 721 are the two tuner inputs, clearly labeled "1" and "2". Set up some kind of way of quickly disconnecting both coax connectors and switching them between tuners. A coax switching system would be best, but in my case what I did was to disconnect both coax lines to the 721, screw coax "barrels" into each coax connector, then add 3' cables with quick disconnects (push-on connectors) to the coax line. Use a pieces of masking tape, label the lines T1 and T2, then connect them to the appropriate inputs on the 721.

3. If you've noted that any single channel has problems more constantly than others, bring this channel up full screen. Additionally, bring up the PiP picture and put the same channel into the PiP window.

4. While watching the set and seeing pixelation on one tuner only (more later on problems in both tuners), reverse the two connectors at the back of the 721. If the problem stays on the same tuner, your problem is internal to the 721, most likely the hardware. Call Dish advanced support for a replacement 721, but be prepared to tell them in great detail how you determined that you have a defective tuner. If this solved your problem, go to "Tips" below.

5. Replace the labeled T1 connector to 1 at the back of the 721, and T2 to 2. Go outside and disconnect one cable from the GND, then check your TV to see if T1 or T2 is now trying to acquire a picture. Using masking tape, label both coax lines between the GND and the 721 appropriately, then reconnect the cable.

6. Disconnect the GND input and output T1 and T2 lines, then reconnect them to each other through coax barrels, thereby bypassing the GND. Ensure that the metal outside of each connector does not touch the GND, each other, or any other metal surface. View your TV, if the pixelation has gone away, your problem is that you have a defective GND ~ replace it. If this solved your problem, go to "Tips" below.

7. Reconnect all lines to the GND, but reverse the lines between the GND and the 721 from where they were in step 5. If the pixelation has switched tuners, chances are that you have a bad run of coax or a bad LNBF. But rather than going out and buying a new run of coax, the smart thing would be to have a piece the right length available for testing. Note that your coax must be RG-6 that is rated for satellite (2.3 GHz or higher), normal TV coax will not do the job. Substitute this test piece for the suspect run of coax, then if the problem goes away, all you need to do is replace a section of coax, then put away the test coax for future problems. If this solved your problem, go to "Tips" below.

8. If the test coax did not solve the problem, try a short run of test coax between the LNBF and the ground block on the side that goes to the tuner that is showing pixelation. If eliminates the problem, replace the short piece of coax and your problem is over. If this solved your problem, go to "Tips" below.

9. Reverse the 2 coax lines at the LNBF. If the problem switches tuners, you have a defective LNBF, replace it and your problem is solved.

Tips

- Someone is going to point a finger at me and say that their unit only pixelates once every two hours or so, so why should they go through all this hassle? In this case the problem probably originates on the incoming transmission and there's nothing you can do about it. This write-up is for those that are seeing excessive pixelation (each user can define excessive for themselves).

- If in step 4 you see pixelation on both tuners at the same time (rare), and bypassing the GND in step 6 does not solve the problem, you need to try substitution to determine where the problem is. Substitute the following one item at a time until your pixelation problem is resolved: Coax sections between the GND and the LNBF, coax sections between the GND and the 721, the LNBF itself, and finally the 721.

- If your problem originates in a single tuner only, but you haven't yet isolated the cause, you can still record programs. Just use the quick coax disconnects at the back of the 721 to insure that the pixelated picture is full screen, then DO NOT turn off the 721 ~ any recordings your have programmed will be taken from the good tuner. Note that just about anything you do with the 721 (turn it off/on for an instant, view the EPG, play back a recording, etc.) can result in the tuners changing places, so be sure the LAST thing you do before recording is ensure the bad tuner is full screen, then leave the 721 alone.

- The problem in my 721 was identified in step 4 as being T2 in the 721 itself. I explained what I had done to Dish advanced support, and they agreed that my 721 needed replacing. They sent me a new one via 2-day UPS, and once it was installed my problem was gone!

- I was told by Dish advanced support that my replacement 721 was guaranteed for 90 days. Since my first 721 became defective after 5 months, I was concerned that my unit might become defective after the guarantee period, and since I owned rather than leased my unit, I'd end up with a $500 paper weight. The technician suggested I get their $1.99/month insurance, which would cover the 721 as well as the LNBF. Since this amount would be automatically added to my bill monthly, this turned out to be cheap and convenient insurance. Additionally, I think it was smart to take this insurance, since 721's seem prone to pixelation problems, so it is very likely that I will be returning this unit sooner or later.

- The worse part of pinpointing the problem is the waiting that you'll have to go through if your problem is intermittent. Be prepared to spend a lot of time in front of your set waiting, waiting, waiting . . .

I have a background in computers and electronics. The toughest problems to fix in both areas are those that are intermittent, especially when the problems originate in the hardware. Note that intermittent hardware problems are somewhat rare in digital circuitry, but that turned out to be exactly what was wrong in my system! Of course hardware problems being so rare, I had suspected software from day 1. When subsequent software upgrades made no difference, I finally decided to take a hard look at the hardware! This delay caused me to miss a lot of good programming, but no longer! :)

Good luck,
Bill

Mark Lamutt
06-04-03, 10:49 AM
Bill, thanks so much for your really excellent post! I hope that it helps out people having this problem.

Big Bob
06-04-03, 10:55 AM
Well done. Thank you.

A couple of questions.
1. couldn't a switch also cause pixelation?
2. did you ever check the temperature when you saw problems?
3. did you note the serial number or some other identifier of you bad unit. I am wondering if there was a bad run of units or if we can identify a sequence of serial numbers that are more prone to this problem. Perhaps there was a board update that would could be identified by serial number or some other identifier.

Thanks for a fine lesson in troubleshooting :)

Kevin Elm
06-04-03, 11:13 AM
Bill, thanks for troubleshooting. My problem has disappeared for now, so it may be some time before I can isolate it. Besides I am moving in the next 2 months.

I agree with Big Bob, temperature seems to play some role. It may be that a bad tuner is more sensitive to high temperatures. My unit is in an enclosed space with little clearance above, but lots of airspace to the sides.

Bill Mullin
06-04-03, 11:19 AM
>>>1. couldn't a switch also cause pixelation?<<<

For purposes of this writeup, the switch and the LNBF are the same thing.

>>>2. did you ever check the temperature when you saw problems?<<<

My old 721 hovered at around 100 degrees, but gave me a lot of problems. The new unit seems to operate at around 115 degrees (which sort of worries me), but no problems yet.

>>>3. did you note the serial number or some other identifier of your<<<

No, but this was something that might have been useful in the future had I thought of it.

- Bill

Mike D-CO5
06-04-03, 06:10 PM
I noticed these symptoms on my son's 508 in his room , but not with my 721 in the living room. I just wonder if shaking or kicking jarring the receiver ,while it was turned on or plugged in ,could cause this pixelation and stuttering that I was seeing with his receiver. My son, who is almost 3, kicks his tv stand and often crams a vcr tape into his vcr under his 508 receiver. His receiver was having all these problems for months.
I just got the replacement receiver ,(free with $1.99 warrenty and credit card autopay), and I am going to put it in my bedroom and use audio /video sender to send the picture to his room.
It might not be related but it does say on all their receivers not to jar or move etc while plugged in because of sensitive hard drive .
Just a thought.

Kevin Elm
06-05-03, 06:20 AM
Originally posted by Mike D-CO5
I noticed these symptoms on my son's 508 in his room , but not with my 721 in the living room. I just wonder if . . . My son, who is almost 3, kicks his tv stand and often crams a vcr tape into his vcr under his 508 receiver

Your 3-year-old son has a PVR in his room? What does he record? Is the hard drive crammed full of every epsidoe of Bob the Builder ?

Bill Mullin
06-05-03, 06:32 AM
Originally posted by Mike D-CO5
I noticed these symptoms on my son's 508 in his roomGreat toy for a 3-year old - I wish I'd had a dad like you!

Yes, shaking a plugged-in 508 can cause damage, but this is not what is going on with the problem 721's that you've read about in this forum.

- Bill

Mike D-CO5
06-05-03, 07:13 AM
He watches Blues Clues , Dora the Exporer, Wiggles, Sesame Street etc, and he has had it since he was just 2 and he comes tome each and every time he wants a new program, " Daddy remote!!"
I wanted to give my son what I didn't have when I was a boy, a choice. My Dad hogged the Tv and we had to watch Sports, Westerns, Documentaries, and very little children's programming. I still remember when my Aunt gave me my own used black and white Philco 13 inch tv. I was in Heaven!!! A lot like when I first got Satellite tv with Primestar then Dish.

Kevin Elm
06-05-03, 07:36 AM
Cool! My kids are a little older, and they have figured out how to use the 721 to time shift. It saves arguing over which show to watch!

My dad tells me what it was like growing up with no TV, just radio.
I tell my kids about B/W TV, only 3 or 4 channels, and NO remote control.
What will my children tell their kids? "I remember when we only got 180 channels with the Dish Everything package." Or, "We could only record 90 hours worth of programming - how primitive!"

Bill D
06-05-03, 09:24 AM
I haven't been following all of the pixelation posts, but this seems like a lot of work for what is almost likely a hardware problem. There have been several documented bad tuner's in 721's. Started back in the fall, I replaced mine in December. It was pretty simple to trouble shoot, leave up the PIP and just watch if one tuner starts dropping in and out, then you more then likely have a bad tuner, if you want to swap cables, probably a good idea since Dish will ask you to do so. Swap cables and do the same, chances are the problem will stay with the same tuner (it did for me).
I mean this is a lot of troubleshooting for Dish's problem. Call them up and get a replacement with as many bad tuners as they have had I can't imagine you are going to get a hard time. I understand you will lose your recordings, watch what you will really miss and get a new one so you don't have to hope that your favorite show is ruined with drop outs.
Just my thoughts after having the same problem.
Bill

jcrash
06-05-03, 09:35 AM
I'm sorry but GADS!

My cabinet is a royal pain in the you know what to get into, all my cabling is in the walls, as I just built this house a year ago. At least for me, this is WAY too much work to find out where the problem MIGHT be.

Thanks for the effort, I'm sure it might help some folks with exposed wiring and hardware, but it doesn't help me.

Bill Mullin
06-05-03, 10:53 AM
Originally posted by Bill D
I haven't been following all of the pixelation posts, but this seems like a lot of work for what is almost likely a hardware problem.Yes it is, but Dish would not agree to replace my 721 until it was 100% established that the problem was truly within the 721. I wrote the full troubleshooting procedure to cover instances when the problem might be anywhere, but if the problem was a tuner within the 721 and you followed the procedures in the order I've listed them, your time would be minimal.



Originally posted by jcrash
I'm sorry but GADS! My cabinet is a royal pain in the you know what to get into, all my cabling is in the walls, as I just built this house a year ago. At least for me, this is WAY too much work to find out where the problem MIGHT be.Yes it is a LOT of trouble, but until Dish will say, "Yes, we've had a lot of bad tuners in the 721", there's not a good option. Trust me - if you call Dish and say that you have a bad tuner, they will say that you are the first to ever report this problem and they will make you go through a lot of the steps I've described. :(

- Bill

Bill D
06-05-03, 07:45 PM
I would think the only step that you would have to go through to rule out anything else is to swap cables going to the tuner. If the problem stays with the tuner... bad tuner, if the problem moves then it could be other equipment.
This is the only thing they asked me to go through.. if they want you to go outside and start switching cables elswhere they should send an installer out. I admire that you made this great list to troubleshoot but if anyone else calls dish, before you do swap the tuner cables and see what that does. Tell them you did this and there shouldn't be any questions, otherwise I would move on to another tech person.
Tell them you had a friend with the same problem and to check this website, there are lost of us that went through this already.

Bill Mullin
06-06-03, 04:13 AM
Originally posted by Bill D
if they want you to go outside and start switching cables elswhere they should send an installer out.Agreed, but if the problem is an item that's not under warranty, you will pay for the service visit. AFAIK, neither the ground block nor the cables are ever warrantied.

Jacob S
06-06-03, 06:21 PM
I have done those steps. Swapped lnbf, then swapped cables, then switched wires to have the same result on the one tuner that pixellates, then try other receivers on the same coax's in which those other receivers worked just fine.

Dish has said that it was the first they ever heard of the problem just as Bill Mullin has said. They will also blame the ground and blame you for why there is a problem.

Bill D
06-07-03, 07:09 PM
Jacob, do you get a new receiver?? Obviously you have a bad tuner, did Dish send you another

Jacob S
06-07-03, 07:47 PM
They told me that it was the first they ever heard of it and to check my ground. I been too busy to mess with it but when I get back home I am going to going to have them replace it.

I have been through this crap with the 501, bad tuner 2 times and hard drive failure once. Now the 721 in which I thought would be different. I dont move the receivers around, they stay right where they are at. I dont have any trouble out of any other receiver than these pvr's. Even the dishplayer never gave me this kind of trouble when I had it for probably around a year or so.