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Hello
I’ve just bought an HDR-2000T from Argos last Thursday as a replacement for my six or seven year old Topfield 5800, which has become unreliable of late (I lost the last ten minutes of a couple of films I recorded over Christmas).
The antenna feed into the box is straight from the antenna downlead. The antenna is a passive wideband Yagi, no head amp, and the television repeater is approx. 2km away and is line of sight (apart from the roof tiles).
The Toppy worked reliably and reported high signal strengths and >90% quality. The Humax reports 30% signal strengths and >90% reliability.
The Humax, however, suffers from significant video/audio breakup. A direct swap back to the Toppy shows no problems. This is in spite of torrential rain – any rain fade is invisible on the Toppy and although it might lower the power into the Humax receiver’s antenna port, I can’t correlate picture breakup against rain. If the Humax is being overdriven, then rain fade would potentially help avoid degrading of the picture (although I admit that the levels might be all over the place and this is a hit-and-miss approach!).
I note from the Humax manual (now packed away ready to return to Argos) that a signal level >30% is recommended for reliable viewing, and I seem to be right on that threshold. I think the Humax dynamic range was quoted as something like -70 to -20dBm which, from memory, is comparable to the Toppy’s receiver.
It is possible that I either have a bad unit (unlikely), or I am overloading the Humax (3/6/10dB pads needed) or the receiver chain is deaf – which could potentially get sorted out via a firmware update if there are adjustable gain stages.
I welcome any advice – I like the Humax in all other aspects (it was easy to set up, and repeatable, on my network and the picture quality when not breaking up was very good).
Welcome to the Forum
1. Any chance you could be tuning in more then one transmitter – channels appearing in the 800 range are a clue to this.
I agree with Barry. Try pressing Menu then Settings>System>Signal Detection. Press right arrow and tell us the list of multiplex channel numbers that you see and the intended transmitter.
Barry, Martin
Many thanks for these suggestions. Annoyingly for me, I did read about the duplicate channels (>800) scenario but I can’t now remember whether or not I saw them, even though I made a note to … make a note …
However, the Toppy only received from one mast, the antenna hasn’t been re-panned and to the immediate rear of the mast is a large (and blocking) such that only one mast is “seen” on that azimuth. I will certainly check it though.
I aim to re-test to meet the circumstances you both describe, in the next few days, and I will certainly report back.
Thanks for your advice – encouraging. I’ll be in touch.
Not sure how long ago you last used the TOPPY.
Firstly at DSO the power of all transmitters went up considerably, this could easily mean that transmitters you couldn’t get before are now in range.
The new box tunes to DVB-T2 mux. The Toppy wouldn’t have even attempted to tune these.
The two boxes may have tuners capable of hanging on to weaker transmissions (I had a Toppy and must admit it never seemed particulary deaf, but back then nothing else was in range).
Nowadays in a similar location a HDR FOX T2 can pull in duplicates from Sutton Coldfield, Ridge Hill and Lark Stoke despite the aerial direction and orientation.
Never bother with autotuning, it’s much easier to guarantee what you are going to tune. Once you have done it once it’s second nature and doesn’t take very long.
Hello Graham – thanks for the info. I was using the Toppy up until last week, the day before I got the Humax, and then once again the day after I removed the Humax due to problems. You make a good point about the multiplexes being different and I didn’t know that.
I shall certainly recheck it as advised, hopefully tomorrow evening and we’ll see what measurements I can note.
Thanks again
Electronic Battle – 11 hours ago »
Hello Graham – thanks for the info. I was using the Toppy up until last week, the day before I got the Humax, and then once again the day after I removed the Humax due to problems. You make a good point about the multiplexes being different and I didn’t know that.
I shall certainly recheck it as advised, hopefully tomorrow evening and we’ll see what measurements I can note.
Thanks again
The HD channels use DVB-T2.
Right – the results of some tests show that the received signal levels appear to be no different when manually tuned compared with the auto-tuned results.
I did a factory reset, confirmed that there were no stored channels and then manually tuned to the five DVB-T channels and single DVB-T2 channel, and noted that they were all showing receive strengths of 41/42% (and quality = 100%). This was with not much rainfall this evening (some, but not as bad as the weekend).
I then added an attenuator (unknown value) and the signal strength dropped to 25% so that suggests (but does not prove) that the tuners were not being overdriven and falsely reporting the Rx signal level. A brief channel surf showed no picture breakup but that was during a ten minute “play” so not conclusive.
I then did another factory reset, again confirmed that there were no stored channels and allowed the automatic setup to complete.
The signal levels were again 41/42% with 100% quality.
In all cases, no channels above ch.790 were seen i.e. no duplicates from other (distant or overlapping) Tx sources.
Given that a few days ago I was seeing a reported signal strength of approx. 38%, and that was during heavy rain and resulting in observed video breakup, suggests that the link margin, at least with this particular box, is not adequate.
I realise that there are more tests I could complete, all the way from measuring the signal power at the PVR’s antenna input through to doing some calibrated attenuation measurements, but that’s too much like work and not enough like hobby! I’m of the opinion that I will take it back to Argos and either try again, or go for a refund and consider my next move.
Whichever happens, let me say thanks for your help and guidance throughout and I will again report any future success.
Not all Humax boxes are identically performing, there are occasional bad ones, If you can get it swapped the replacement might work better.
Hello Owen
I decided to get a refund my purchase; I might repurchase later in the year once any firmware update(s) occurs. In the mean time I shall keep an eye on this well-informed forum.
I currently have both a 2000t and a Fox-T2 in my house and so can directly compare the two. My Fox-T2 shows an average signal strength of 50% on all MUXs whereas the 2000t shows an average of 33% and I’ve had a couple of signal breakups. Humax are clearly using less sensitive tuners, probably to save money.
moo – 3 hours ago »
I currently have both a 2000t and a Fox-T2 in my house and so can directly compare the two. My Fox-T2 shows an average signal strength of 50% on all MUXs whereas the 2000t shows an average of 33% and I’ve had a couple of signal breakups. Humax are clearly using less sensitive tuners, probably to save money.
I think you’re placing too much trust in the 50% and 33% actually meaning something absolute. It could mean that when the Fox-T2 says 100% the 2000T is simply at 66% with the same signal strength, but they rescaled it so that higher signal levels can be discerned.
You can only compare percentages on identical hardware with identical software.
moo – 5 hours ago »
Humax are clearly using less sensitive tuners
I agree.
But not because of the metre readings for the reason that Owen gave.
http://myhumax.org/forum/topic/hdr-2000t-poor-signal-strength/page/2#post-23224
Owen Smith – 1 hour ago »
I think you’re placing too much trust in the 50% and 33% actually meaning something absolute. It could mean that when the Fox-T2 says 100% the 2000T is simply at 66% with the same signal strength, but they rescaled it so that higher signal levels can be discerned.
You can only compare percentages on identical hardware with identical software.
Well I don’t believe that, as the Fox-H2 has never had issues with signal breakup and has worked flawlessly. The 2000t works most of the time but 20% of the recordings always say loss of signal and I’ve seen it break up on live TV a few times too.
There were also reports of the very latest Fox-T2 models having a different less sensitive tuner than the older models so it would make sense that the two share hardware.
I’m happy to accept hard evidence that the new tuners are less sensitive as given in the quoted post by someone else. But the signal strength meters mean nothing, it’s an arbitrary nunber not comparable on different models.
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