OK guys, I'm going to need some help here -
The hard drive I had in my MG35 went PFFT (spindle motor driver).
The Mediagate has suffered in that SMD chip U29 has blown. The box will power up fine, the hard drive (new one) has power, but won't spin up.

This isn't a problem to me (work on electronics everyday), what is a problem is identifying U29. The code marking is CU4F, it's a 5-pin SOT-153, it seems to run off 5V and connect to the nearby 74LVC32 logic.

I'm trying to work out what it is, but if someone knows - please tell me!

Thanks.

Another (frustrated) Ian

Well, my current thoughts are that the device is a single-gate logic device.
The pinouts seem to match, but I still don't know which type of gate.

Oh well, more searching.

Another Ian

Identified:
Texas Instruments SN74LVC1GU04 single-gate unbuffered inverter, code mark CU4_

Another happy Ian

Hmmm. I'm surprised that such a simple device would be the first to go... Was this part overheated or what?

The magic smoke escaped!
Looks like both the single gates are damaged.

The box boots up fine, the front panel works, remote control isn't sensed, and when it's powered down it just powers up again.

I've found a source for the gates so I'll replace them and see if it works.

Another Ian

Update:
Both single-gate inverters replaced, 74LVC08 and 74LVC32 replaced.
Mediagate now operating but audio is missing.

Another Ian

The magic smoke escaped! Sometimes I wonder if we speak the same language! :D Does this mean that your unit actually got so hot that smoke came out? The box boots up fine, the front panel works, remote control isn't sensed, and when it's powered down it just powers up again. Urp. Missed this fact until you posted in the other thread. Now, since the other chap did NOT have a hd failure, but nevertheless suffered the same symptoms, I am wondering if it's possible that your Mediagate "smoked" your disk, and not vice versa. Both single-gate inverters replaced, 74LVC08 and 74LVC32 replaced. Mediagate now operating but audio is missing. Now that's very interesting. If you are about to resort to following traces from the RCA jacks on the back to other components upstream, can you tell us whether the audio comes from the EM8511 or the Wolfson (part no. WM8728S) 192kHz Stereo DAC?

Well, hmmm. I will now offer my own answer and prediction. The EM8511 has an audio decoder DSP, but the outputs are SPDIF and I2S. According to Wikipedia,
I2S, or Inter-IC Sound, is an electrical bus interface standard used for connecting digital audio devices together. It is most commonly used to carry PCM information between the CD transport and the DAC in a CD player. The I2S bus separates clock and data signals, resulting in a very low jitter connection. Jitter can cause distortion in a digital-to-analog converter. The bus consists of three lines, a clock line, a word select line, and a multiplexed data line. So... That being the case, the EM8511 does not produce an analog audio signal for the RCA jacks on the back. The latter must be connected to the Wolfson DAC instead. You could hook up the Mediagate's SPDIF output and see if it has a valid signal. If so, it's likely the EM8511 survived and your DAC is toast.

Sometimes I wonder if we speak the same language! :D Does this mean that your unit actually got so hot that smoke came out? Urp. Missed this fact until you posted in the other thread. Now, since the other chap did NOT have a hd failure, but nevertheless suffered the same symptoms, I am wondering if it's possible that your Mediagate "smoked" your disk, and not vice versa. Now that's very interesting. If you are about to resort to following traces from the RCA jacks on the back to other components upstream, can you tell us whether the audio comes from the EM8511 or the Wolfson (part no. WM8728S) 192kHz Stereo DAC?

Well, hmmm. I will now offer my own answer and prediction. The EM8511 has an audio decoder DSP, but the outputs are SPDIF and I2S. According to Wikipedia,
So... That being the case, the EM8511 does not produce an analog audio signal for the RCA jacks on the back. The latter must be connected to the Wolfson DAC instead. You could hook up the Mediagate's SPDIF output and see if it has a valid signal. If so, it's likely the EM8511 survived and your DAC is toast.
I know you probably already checked, but one of the items in the "setup" menu is how to output the audio. It can be set for analog audio or digital. If set wrong for your cabling and receiver, no output might result.

Also.... the MG-35 has no way to decode DTS streams.... those must be output as a digital output and decoded in your reciever.

Try a different avi file, or a different ISO image.

Great news you got the MG-35 booting again.

Joe L.

Thanks for the wishes guys.
Audio is a digital stream from the RealMagic into the Wolfson. The WM8728 is set to hardware mode (simple interface), 24-bit I2S.

I don't blame the Mediagate for the HDD failure - the spindle driver has a nice hole in it (its an old Western Digital), but because the Mediagate uses low-voltage components (6V - 7V maximum Vcc) it can be sensitive to spikes on the 5V line.

Sounds like a 1W 5.5V zener might be useful. ;)

I don't have a digital receiver, only a good-old analogue stereo amp.
Files are MP3 audio, Setup double-checked as analogue output.

I'm convinced the WM8728 has died too. :(

Another Ian

Yes, the unit did actually smoke - mostly from the harddrive, but also one of the single-gate chips had a burn-out too.

I dropped mine soon after purchase :( After powering on the same U29 "smoked" literally... I've seen at least one other post with a similar problem (they claimed a reversed supply input though). Now I'm thinking perhaps a design issue.

Bert

Sometimes I wonder if we speak the same language! :D Does this mean that your unit actually got so hot that smoke came out?

LOL. I remember the first time I heard about the magic smoke, and I was like "Huh?".

Essentially the theory goes that all those neat little electronic parts contain magic smoke that allows them to work, and they cease to function when you let the magic smoke out. ;)

LOL. I remember the first time I heard about the magic smoke, and I was like "Huh?".

Essentially the theory goes that all those neat little electronic parts contain magic smoke that allows them to work, and they cease to function when you let the magic smoke out.

That's the one! :cool:

Guys new to the website and forum however not really that new to the MG35, I have been using the USB way of transferring files from the PC HDD's in the past.
I have recently purchased a set of ethernet network electical plug devices and am suffering from a few things.
Firstly the MG35 can see the network and the shared drives intermitantly, when it does see them I can navigate via my PC, HDD's and see shared folders there in. However, when I get to the last navigatable shared folder it comes up with incorect sharing permissions etc.
The PC/network set up is via as I said the ethernet LAN electrical plug devices (netgear 200mbps), into a linksys ADSL wireless router (with 4 port switch).
I have set up the IP and subnet mask as per instructions, is there something Im doing wrong and can anyone point me in the right direction?

Mick
mickhilton@hotmail.com

@ Mick..

Welcome..

My first thought here is that your network may be dropping out intermitantly, I have head very "mixed" reports about networks that use "ethernet network electical plug devices".As often they are effected by various interference sources.

Have you tried do a Extended "ping" of your MG-35 from your PC - I mean set the ping to ping all night (or a few hours) and then look at the log in the morning to check for any dropouts.You wiil need to setup NDAS todo this , so your PC can "see" your MG-35.

Also have you check your firewall/anti-spyware software is off or letting thru the needed ports?

Regards,


Teddy

Teddy,

Many thanks for the reply, NDAS is up and running however it does have problems seeing the MG35 at times so your assumption would appear to be spot on so far, I have run ping tests but only for short periods and it would appear from the results that intermitent network problems are the cause as I generically get 1 receive and 3 packets timed out/lost.
The only other solution would be to run a 20m ethernet cable at this rate, if anyone knows of any other solution (not wireless) Im all ears.

Mick

Teddy,

Many thanks for the reply, NDAS is up and running however it does have problems seeing the MG35 at times so your assumption would appear to be spot on so far, I have run ping tests but only for short periods and it would appear from the results that intermittent network problems are the cause as I generically get 1 receive and 3 packets timed out/lost.
The only other solution would be to run a 20m ethernet cable at this rate, if anyone knows of any other solution (not wireless) Im all ears.

MickIf your "ping" results are that bad, you will not be able to play media files over the link.

I originally tried an equivalent "slingbox" ethernet over powerline extender for the MG-35 in my bedroom. It gets between a half and two thirds of the throughput of a direct LAN connection.

It is NOT fast enough to watch a DVD ISO image, but is OK for MP3 or smaller compressed .avi files.

I replaced it with a wired lan connection. (Now, my wife and I can get to and play anything on our media server)

Your poor "ping" performance seems to indicate a really poor signal. Make sure you do NOT plug your POE units into surge-protectors, but directly into the power outlet. Many surge protectors will filter out most of the signal.

Joe L.