Listen Up Octagon sf8008 no output

[Channel Hopper]

plus a high pitched whine from inside. There is also a faint whiff of plastic. I only went out for half an hour as well.

This receiver has an external power supply so I would suspect the only place where the noise might come from is the front panel display, but that is also dead.

Will take the lid off later and have a sniff/listen for any clues.

 

[Terryl]

Well if you let the smoke out of it, it will never work right, you have to put the smoke back in, then it will work again..........The high pitched whine may be from the smoke generators,(plastic IC chips) they could make that noise, and the smoke may smell like plastic.

 

[4wd]

Like in old cars and bikes, if the smoke escapes from within it's sealed confinements, one has to plug the leak, then buy new smoke from Lucas and inject it, and all will be fine.

 

[Tururu]

The power supply, never use it, give what it says, period.
Some source when breaking, you can hear the high frequency oscillator of the commutation by lowering the frequency and being audible.
Inside the receiver has nothing that can produce noise, hopefully it is not a condenser, which I have 3 years ago (2 satellite tuner), I use it with a fatter source and without problems.
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La fuente de alimentacion, no la use nunca, da lo que dice y punto.
Alguna fuente al romperse, puedes oir el oscilador de alta frecuencia de la conmutacion al bajar la frecuencia y ser audible.
Dentro el receptor no tiene nada que pueda producir ruido, esperemos que no sea algun condensador, el que tengo hace 3 años (2 tuner satelite), lo uso con una fuente mas gorda y sin problemas.

 

[Channel Hopper]

The PSU is an external one and the noise comes from the receiver.

I've taken the lid off - warranty sticker now void - and it does appear to come from near the CI slot, possibly the IF tuner but I will remove the PCB from the case to check further / closer.

 

[solly]

it better to buy 12v 5a adapter and replace it

 

[maxi_power]

Some photos would be cool...

 

[Terryl]

Some photos would be cool...

I agree...Photos would be nice.

 

[Tururu]

The PSU is an external one and the noise comes from the receiver.
I've taken the lid off - warranty sticker now void - and it does appear to come from near the CI slot, possibly the IF tuner but I will remove the PCB from the case to check further / closer.

En la zona del lector de tarjetas puede ser un convertidos de tension que tiene para el usb 3.0, luego lo miro.
Tengo unas fotos que le saque el 24-enero-2020, para los compañeros, luego pongo otras mejores.
Queria ver el chip del tuner.
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In the area of the card reader can be a voltage converts that it has for USB 3.0, then I look at it.
I have some pictures that will be taken on January 24, 2020, for colleagues, then I put better ones.
I wanted to see the tuner's chip.

 

[Terryl]

I've had inductors in a power supply circuit make funny noises when they are built too cheap, had too much current pulled through them, or about to go bad or have gone bad, touch the top of the 100 uH inductor inside the red outlined area in the second photo with a plastic or ceramic tuning tool and see if the ringing/whining stops.

If the inductor was under rated for the DC current spec in that circuit, or in someway a power overload was drawn on that circuit, it could smell like burning plastic

 

[Channel Hopper]

First test before the full dismantle.

Audio pitch is 7.5kHz and looks to be from under the PCMCIA housing.

 

[Channel Hopper]

And having dismantled as far as I can (the card slot mechanism is hard soldered to the main board) , the whine appears to come from components buried deep within. I can't see anything that looks damaged, though the whiff of plastic was the second clue after no lights on the front panel.

Pressing on the coil shown doesnt make any difference to the noise I can hear.

I doubt I can get any further to a fix without sending back to Germany.;

 

[maxi_power]

En la zona del lector de tarjetas puede ser un convertidos de tension que tiene para el usb 3.0, luego lo miro.
Tengo unas fotos que le saque el 24-enero-2020, para los compañeros, luego pongo otras mejores.
Queria ver el chip del tuner.
--------------
In the area of the card reader can be a voltage converts that it has for USB 3.0, then I look at it.
I have some pictures that will be taken on January 24, 2020, for colleagues, then I put better ones.
I wanted to see the tuner's chip.

Hi,
You can use both tuners at the same time without overheating problems?

 

[maxi_power]

And having dismantled as far as I can (the card slot mechanism is hard soldered to the main board) , the whine appears to come from components buried deep within. I can't see anything that looks damaged, though the whiff of plastic was the second clue after no lights on the front panel.

Pressing on the coil shown doesnt make any difference to the noise I can hear.

I doubt I can get any further to a fix without sending back to Germany.;

After removing the guarantee seal, maybe it doesn't pay.

 

[Channel Hopper]

Of course, but I can point them back to this thread to know it wasn't dismantled for a reason other than identifying if the fault was something elementary.

So, what components on a satellite receiver front end oscillate at 7.5 - 8 kHz when faulty ?

 

[maxi_power]

I was also tempted to open mine, but maybe I have to send it to RMA first.
The worst thing is that the problem of mine only occurs in certain circumstances, may not detect the problem in tests.
Since I started using the 2 tuners at the same time, the DVB-T tuner loses signal if the box is not being ventilated.

 

[Channel Hopper]

There is, or isn't a power delivery system on the terrestrial side with the SF8008 ? It is odd that you might find the unit overheats unless it is putting power out to something like a masthead amplifier. What is the ambient temperature of the room where you have it installed ?

I used the terrestrial tuner maybe twice in six months, just to look at the updates on UK television. I've not had both ports connected at any one time.

 

[maxi_power]

I only started having problems when I started using the box as a fallback tuner.
I have nothing in the installation that can cause problems.
Now it's winter and it's been cold here by PT.

 

[dreambox1959]

I only started having problems when I started using the box as a fallback tuner.
I have nothing in the installation that can cause problems.
Now it's winter and it's been cold here by PT.

here is 4 power supply :


here is lnb supply

 

[Terryl]

Of course, but I can point them back to this thread to know it wasn't dismantled for a reason other than identifying if the fault was something elementary.

So, what components on a satellite receiver front end oscillate at 7.5 - 8 kHz when faulty ?

The main DC power input to the receiver is from an external +12 DC wall wart right??

So somewhere there is a voltage multiplier circuit or switching circuit to get the +18 volts DC needed to switch to a different transponder on the LNB, this voltage multiplier or switching circuit could have a damaged component in it, (thus the burnt plastic smell) and maybe causing the ringing noise, cant go too much further with out a schematic of the unit.

One way to look for a bad IC or other component would be a thermal scan of the PCB, this would give you an idea on a bad part by it's thermal image.