43 replies to this topic

[Erik Slagter]

That surely suggests it's related to power supply, as my switch is self-powered (and also delivers power to the LNB's).

[littlesat]

Nope... When i do the same with another receiver do not have dropouts.. I can not see power supply drops on the tuner output too with a scope... I must be something internally....

[roldon]

I'm actually tending to agree with Erik. The only thing I am sure is that it is related to the tuner on/off/switch or something like that. And it is something internally indeed. Does it suggest that the DM8000 is bugged ? Or the power supplied by the tuner is not strong enough for both the diseq and the LNB ? A 800 € box ?

I have the same LNB's and the same dise'q since many years. I've never experienced that with the Technisat. But : the technisat doesn't switch tuners. It always uses different tuners while recording and watching even on the same transponder.

[Erik Slagter]

It doesn't have to be power supply itself that gives the problem, it can also be the tuners that interfere with each others power supply.

On a side note, do you use only the built-in tuners, or do you have extra tuners?

[littlesat]

In suggest turning on a tuner might glitch internally the other tuner... Verified with a scope that the output of the current tuner does not glitch...
So I would recommend when when tuner is turned on to keep also the other tuner being turned on..

With a power supply switch you do not have a sudden increased currentdraw that might glitch the other tuner somehow...

[Erik Slagter]

With a power supply switch you do not have a sudden increased currentdraw that might glitch the other tuner somehow...

I guess you mean a switching power supply Any good power supply will prevent glitches (or in fact surges), it's not a trademark of a switching power supply . Still you will always be able see some small glitch on a power rail if anything is switched on or off. Depending on how sensitive the connected devices are, they may or may not suffer from it.

The fact that with a self-powered multiswitch there is no such problem says a lot, imho.

I think pieterg is very well in the right direction here, the dmm enigma probably works around the problem by switching tuners off less often.

[littlesat]

Enigma does not switch off tuners

[Erik Slagter]

Oh yes it does! Try the loop-through, it will work when enigma does not use the tuner and will stop work when enigma uses the tuner!

[roldon]

It doesn't have to be power supply itself that gives the problem, it can also be the tuners that interfere with each others power supply.

On a side note, do you use only the built-in tuners, or do you have extra tuners?

I only have the built-in tuners.

[roldon]

Nope... When i do the same with another receiver do not have dropouts.. I can not see power supply drops on the tuner output too with a scope... I must be something internally....

Assuming that it may be power related or an interference between tuners, why doesn't it occur on timed recordings while in standby ? When the second recording starts, the first one is not affected. It only occurs while watching.

[littlesat]

Where are the tuner off and on calls the. In enigma2...?

[Martin_B]

I had the same "problem" (xtrend 9500).

Default value:

cat /sys/module/dvb/parameters/lnb_power_off_in_standby
=1

edit
/etc/modules-load.d/_et9x00.conf
dvb lnb_power_off_in_standby=0

reboot and it works without these dropouts.

cat /sys/module/dvb/parameters/lnb_power_off_in_standby
=0

This works perfectly and 100% reproducibly for me.

The dafault value seems to be different in different types of boxes ET 9000 (=0), 9100 (=0), 9200 (=1), 9500 (=1)

Regards Martin

Edited by Martin_B, 17 February 2013 - 06:14.

[littlesat]

It should be power off in standby as the description suggests and not power off a tuner when it is not used???.....

[Martin_B]

Yes... but it definitely causes "power off" in in operating (not standby) mode...

Edited by Martin_B, 17 February 2013 - 07:30.

[Dimitrij]

Yes... but it definitely causes "power off" in in operating (not standby) mode...

I can prove that it is not, at least on my 9000...
_et9x00.conf

....
dvb lnb_power_off_in_standby=1 simul_hdmi_scart=0

View channels with tuner А(fixed antenna)
Tuner В connected via motor( Moteck rSG 2100A)->look at the engine and see that the lights up green
Switch to standby ->indicator on the motor stopped working(no green power)

Edited by Dima73, 17 February 2013 - 09:28.

[Martin_B]

Hi Dima,

maybe (because of my poor english) I was not able to express myself properly.

dvb lnb_power_off_in_standby=1
Tuners are switches off in standby.

But there is also an effect in operation mode.
Tuners are switched on/off when in/not in use.
And this causes exactly the behaviour described in post #7.

Regards Martin

[Erik Slagter]

IMHO it was quite clear.

[malakudi]

lnb_power_off_in_standby=1 means exactly that, turn LNB power off when tuner is in standby. Not when receiver is in standby. So tuners turn off power to LNB when idle.

[roldon]

Well, just another idea someone perhaps could investigate. Could it be related to the LNB polarity change rather than power on/off ?

[littlesat]

Indeed it could also be related on switching at the LNBs.... but then I suggest something is bad regards the LNBs