[linux-dvb] Preliminary support of Hauppauge Nova-T 500 Dual
patrick.boettcher at desy.de
Wed Sep 20 11:55:02 CEST 2006
On Wed, 20 Sep 2006, Jose Alberto Reguero wrote:
> I made a experiment, and take the agc params from dib3000p_mt2060_agc_config
> from dibusb-common.c line 170 and put in bristol_dib3000p_mt2060_agc_config
> from dib0700_devices.c line 26 except ".setup" and I have much beter results.
> I can tune to this frquency with LNA off and with LNA on with good results
> (similar ber, a little better with LNA on).
Uh la la. Never ever do that. AGC settings are (most of the time)
determined by a process of calibration (checking for sensitivity, high
power, backoff in different adjacent channel scenarios (Nordig, MBRAI)).
The settings which are there are optimized for the nova-t 500 (knowing
that there is an LNA).
If you now use different settings, they may work very good for you, but
most likely very bad for others (with other reception conditions). The AGC
calibration is always a compromise to achieve usable reception for
That reception is working with LNA on and off is, btw, no indicator. The
LNA should be used, if you live in an area, where signal are very low.
That the Nova-T 500 has only one LNA for both channels is a bit unlucky,
that's why it is now switchable with a module parameter.
So once again: unless one is not 100% sure of what he/she is doing, DO NOT
TOUCH AGC parameters. Otherwise it will be quite impossible to support
people reporting bad reception quality.
Mail: patrick.boettcher at desy.de
More information about the linux-dvb