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Bug #2578

Cosmetics: QAM tuner called DVBC in web interface

Added by Olli Salonen over 7 years ago. Updated over 7 years ago.

Status:
New
Priority:
Normal
Assignee:
-
Category:
User Interface
Target version:
-
Start date:
2014-12-29
Due date:
% Done:

0%

Estimated time:
Found in version:
3.9.2182
Affected Versions:

Description

A TV tuner for North American TV standards that supports ATSC and QAM shows up in tvheadend web interface as:

Device LG Electronics LGDT3305 VSB/QAM Frontend : DVB-C #0
Device LG Electronics LGDT3305 VSB/QAM Frontend : ATSC #0

I believe it would be more correct to call the cable tuner as "QAM #0" (or J83 ANNEX B #0) as DVB-C clearly points to the European cable standard.

http://en.wikipedia.org/wiki/QAM_%28television%29

Here's the dvb-fe-tool output of the tuner:

INFO Device LG Electronics LGDT3305 VSB/QAM Frontend (/dev/dvb/adapter1/frontend0) capabilities:
INFO CAN_8VSB
INFO CAN_INVERSION_AUTO
INFO CAN_QAM_64
INFO CAN_QAM_256
INFO DVB API Version 5.10, Current v5 delivery system: ATSC
INFO Supported delivery systems:
INFO [ATSC]
INFO DVBC/ANNEX_B

History

#1

Updated by Jaroslav Kysela over 7 years ago

Your tuner probably can do both (or at least driver thinks so):

INFO DVBC/ANNEX_B
#2

Updated by Olli Salonen over 7 years ago

Jaroslav Kysela wrote:

Your tuner probably can do both (or at least driver thinks so):

No, not really. For some reason the real DVB-C (a.k.a. ITU-T J.83 Annex A) is DVBC/ANNEX_A in DVBV5 and the American QAM (a.k.a. ITU-T J.83 Annex B) is DVBC/ANNEX_B there.

So in order to support DVB-C the tuner must report DVBC/ANNEX_A capability, which my tuner does not report. Also the demodulator (LGDT3305) according to datasheet is only "Compatible with ATSC A/53 8/16-VSB, ITU-T J.83 Annex B 64/256 QAM specification."

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