Kitz Forum

Broadband Related => FTTC and FTTP Issues => Topic started by: digit101 on June 26, 2019, 06:00:52 PM

Title: Any way to increase upload? - long way from cabinet
Post by: digit101 on June 26, 2019, 06:00:52 PM
Hi, is there any way to increase the upload? I have replaced modem with zyxel 8924 to gain access to line stats.

There is a ferrite ring on the power cable, twisted rj11 vdsl lead and mk3 filter.

I guess the only thing left is high quality power supply / linear psu?

Line length is long at 1450m
Cabinet is eci :(

on dsl checker it shows upload speed as 3.2 - 1.6 for clean A

The line stats are:

   VDSL Port Details       Upstream         Downstream
               Line Rate:      1.606 Mbps       27.795 Mbps
    Actual Net Data Rate:      1.587 Mbps       27.748 Mbps
          Trellis Coding:         ON                ON
              SNR Margin:        6.3 dB            6.4 dB
            Actual Delay:          0 ms              0 ms
          Transmit Power:        7.0 dBm           7.0 dBm
           Receive Power:       -6.6 dBm         -13.8 dBm
              Actual INP:        0.0 symbols       0.0 symbols
       Total Attenuation:        0.0 dB          31.5 dB
Attainable Net Data Rate:      1.690 Mbps       27.768 Mbps
====================================================================================
  VDSL Band Status        U0      U1      U2      U3      U4      D1      D2      D3
  Line Attenuation(dB):    7.6    61.8    62.2     N/A     N/A    26.1    76.2    90.3   
Signal Attenuation(dB):    7.6    59.2     N/A     N/A     N/A    24.5    77.7     N/A   
        SNR Margin(dB):    7.3    6.3     N/A     N/A     N/A    6.4    6.5     N/A   
         TX Power(dBm):    0.9    5.8     N/A     N/A     N/A    10.6    2.4     N/A   
====================================================================================

Title: Re: Any way to increase upload? - long way from cabinet
Post by: burakkucat on June 26, 2019, 07:13:58 PM
From the information that you have shown, no there is nothing you can do to increase the US speed.  :no:

Your QLN plot is truncated and all sub-carriers (tones) below 3472 are not shown. But I doubt that the missing segment will disclose anything significant.
Title: Re: Any way to increase upload? - long way from cabinet
Post by: digit101 on June 26, 2019, 07:35:26 PM
Hi, thanks for the reply. I just noticed I uploaded the QLN zoomed in

here is the correct one:
Title: Re: Any way to increase upload? - long way from cabinet
Post by: burakkucat on June 26, 2019, 09:01:38 PM
Ah, that's more like it.

There is nothing too out of the ordinary . . . I see the DSPBO notch (a manifestation of the CAL), a very small amount of RF ingress and a slight degree of cross-talk with other VDSL2 circuits. Nothing that you can influence or change.

Look at the Hlog plot. (Yes, I realise that is also zoomed-in). Compare the amount of green with the amount of red. They are your US and DS bands, respectively. Your circuit, due to its length, is only using the US0, DS1, US1 & DS2 bands.