Freeview reception problem / Netgem advice pls

Tenex

Distinguished Member
Joined
Mar 2, 2003
Messages
7,632
Reaction score
1,056
Points
1,415
Receiving Freeview from Crystal Palace & I'm getting intermittent problems with ITV channels.


I first tried an Panasonic box and it worked OK for 24 hours then it lost the ITV services & C4 & C5 from Friday to Sunday. In case it was the box I swapped it for a Netgem and that seemed OK for the first few days but then it lost ITV services and C4 only (C5 is OK). For the past 3 days there has been an occasional pixellated half picture at best on ITV & 4 and no sound.

When the picture is present it's very good (as are the other channels) - pity about the lack of content though. The aerial signal for terrestrial is good (except for the usual poor BBC1 summer reception and the fact it's hilly around here, so some ghosting on 5). I noticed another poster say reception was bad when cloudy but I'd say reception is bad when there's high barometric pressure - as the past few days.

Does this sound like I need a replacement aerial? I'm tempted to suggest that if it's a new aerial then I wonder whether I shouldn't throw in the towel and get Sky ... :thumbsdow I'm reluctant to do either as I may be moving.

Advice appreciated.




And a couple of questions for Netgem users:

-haven't got a convenient phone point nearby (all DECT) so am I missing out on anything essential 'cos it hasn't dialled home?

-is there a way of viewing the signal strength?

-the quick setup says see the handbook re. connecting a VCR but the handbook seems to miss the topic completely, how do you set the VCR channel?
 
Originally posted by Tenex

-is there a way of viewing the signal strength?

Yes there is. Bring up the menu, then it's My Player -> Help -> Diagnostics -> TV Signal


-the quick setup says see the handbook re. connecting a VCR but the handbook seems to miss the topic completely, how do you set the VCR channel?

Not quite sure what you mean, as the diagrams in the manual seem pretty straight forward from what I remember, although the one for connecting the I-Player plus VCR and DVD to a TV with only one SCART is incorrect if you want to use R1 (and would probably be scuppered by Macrovision).

If you're trying to record from the I-Player, you need to set your VCR to record from whichever AUX input you've connected to - if you're doing a timer recording, you'll need to set the timer on the VCR to record from the AUX channel for the same time that you've set the timer on the I-PLayer
 
Thanks for the comments. What's the difference between signal strength and quality? The ITV channels seem to have poor S/NR - would that be the reason they drop out? Strength seems to be much the same across all channels.

I was trying to set the VCR up without a SCART using RF only but I assume that's not possible? No DVD connected as yet. I'll get another SCART this weekend.
 
Originally posted by Tenex
Thanks for the comments. What's the difference between signal strength and quality? The ITV channels seem to have poor S/NR - would that be the reason they drop out? Strength seems to be much the same across all channels.

I'm not sure what the signal strength actually relates to either, as I get similar strengths across all the channels (although the ITV channels seem to be a bit higher than the norm), yet widely different qualities of recepition.

I believe that Signal Quality, SNR and the BER (I think this is Bit Error Rate) are the important factors. If the BER is high (I've seen it go as high as 99) chances are you'll see the Signal Quality drop extremely low, and you'll be watching the coloured block show on TV, with the occasional bleep of sound.

I'm not sure how much of an effect the SNR has, as channels with low SNR have still had a very low BER level and good reception, so I'm guessing it's not a straightfoward case of "You have low SNR, you're in trouble" situation.


I was trying to set the VCR up without a SCART using RF only but I assume that's not possible?

No, the I-player apparently doesn't have an in-built RF modulator, it's just a pass through. It's a teensy bit annoying as it would certainly save me some hassles until I can get my new main TV (which isn't likely to be for a few months yet unfortuantely)
 
OK connected the third SCART (well second to the Netgem) and recording from it isn't without problem there seems to be a lot of noise in the picture for whatever reason? :confused:

Going back to the problem ITV reception and bit errors etc, there aren't any errors at all on any except the ITV channels and they seem to be there even when the Signal strength is high so I wonder if there's something else contributing to it? :confused:

Also and this surprised me: the Netgem seems to be incredibly sensitive to positioning. I noticed this when attaching the second SCART - suddenly the picture broke up and putting the I-player down stabilised it again. Then I tried to place it on the VCR (which was off) and the picture was lost completely. The I-player appears to need to be placed as far away from anything as possible from the small experiments I tried. Even without the second SCART it's the same.

Does this mean the unit is particularly poorly shielded? Raising it on 2 video tapes seemed to be the best compromise I could come up with (it's under a new Panasonic 32TXPL10 alongside a VCR - I dare not put anything else down there - and on a surge protected socket). There is some picture break up even when I place my hand over the unit, not what I'd expected from a product at the higher end of the market.

Minor Q: a couple of times in the past few days when switching between TV and Netgem and VCR the lipsync has got way out on the Netgem - is this a common problem with STBs? Switching off and on again seems to fix it. :confused:
 
Interesting... I bought one yesterday and updated the S/W and tuned it in and all channels were around 80% signal strength. I was very happy with this since I have a very old dodgy aerial and old cable and wasn't expecting it to be so good.

However, later in the night when I watched again the signal was down to 70% on some channels and 50% on others. I put this down to a change in the weather (but was surprised how much it had changed).

Having read this thread now though, I've just remembered that I moved the box from the carpet where I initially set it up, to on top of my VCR. Could this be the problem?? I will check tonight.
 
I keep forgetting which is first in the list Strength or Quality. Anyway the first is generally 75% +/- 5% on most channels but regularly gets over 80%, but the second (quality?) is only ever 31-37%. No bit rate errors on any channel except ITV.

You can check if moving it makes a difference - mine performed best on its side last night but I ended up having it on 2 video tapes again.

Let us know if moving the I-playr makes difference - it must surely be down to poor shielding if moving it around or placing other things near it actually degrade the signal?

Anyone have an email contact for Netgem?
 
Originally posted by Tenex
OK connected the third SCART (well second to the Netgem) and recording from it isn't without problem there seems to be a lot of noise in the picture for whatever reason? :confused:

Can't say i've noticed this, although I'm recording in LP on a well-used tape, so the picture is never going to be pristine anyway...



Going back to the problem ITV reception and bit errors etc, there aren't any errors at all on any except the ITV channels and they seem to be there even when the Signal strength is high so I wonder if there's something else contributing to it? :confused:

I don't think the signal strength would have anything to do with the BER, as you could have the strongest signal in the world, but if you're getting interference from somewhere, I'd expect the box to start detecting errors. As I think I've said, I'd expect a high BER to affect the Signal Quality



Also and this surprised me: the Netgem seems to be incredibly sensitive to positioning. I noticed this when attaching the second SCART - suddenly the picture broke up and putting the I-player down stabilised it again. Then I tried to place it on the VCR (which was off) and the picture was lost completely. The I-player appears to need to be placed as far away from anything as possible from the small experiments I tried. Even without the second SCART it's the same.

I can't say I've noticed this myself. My I-player is currently sat at the top of a stack of components (in descending order in the stack - DVD player, MD deck, VCR), and is only about six or seven inches from the TV I'm using (which is only a crappy 14" thing), and of the image/sound breakdowns I get, I don't think any of them are attribitual to the proximity of other components to the I-Player, although if I get teh chance I'll try shifting the position of the box.




Minor Q: a couple of times in the past few days when switching between TV and Netgem and VCR the lipsync has got way out on the Netgem - is this a common problem with STBs? Switching off and on again seems to fix it. :confused:

I do seem to have been getting a few moments when I've been in the menus and come out to the main picture where the picture has been frozen until I change channels forward and back
 
Originally posted by Tenex
I keep forgetting which is first in the list Strength or Quality. Anyway the first is generally 75% +/- 5% on most channels but regularly gets over 80%, but the second (quality?) is only ever 31-37%. No bit rate errors on any channel except ITV.

The first one is Signal Quality, the second (with Channel # and Frequency in between) is Strength, then BER, then SNR (Signal to Noise Ratio) (topped off by Demod:).

It might be helpfull for us to try and get an understanding of what's going on if you can keep tabs on the SNR as well, as I'd have thought that the higher this is, the lower the BER should be, and the higher the Quality should be.



Anyone have an email contact for Netgem?

There's this one off the web site for
Netgem customer support
 
Originally posted by cerebros
Can't say i've noticed this, although I'm recording in LP on a well-used tape, so the picture is never going to be pristine anyway...

In my case it's a bar of interference 1/3 of the way down the screen. Having moved the I-player again it seems to have gone but the recording is still "noisy".


I can't say I've noticed this myself. My I-player is currently sat at the top of a stack of components (in descending order in the stack - DVD player, MD deck, VCR), and is only about six or seven inches from the TV I'm using (which is only a crappy 14" thing), and of the image/sound breakdowns I get, I don't think any of them are attribitual to the proximity of other components to the I-Player, although if I get teh chance I'll try shifting the position of the box.

Definitely not my experience.


I do seem to have been getting a few moments when I've been in the menus and come out to the main picture where the picture has been frozen until I change channels forward and back

Cycling the power is all it takes but it's irritating.

I'll try moving it around tonight and note any variations in the stats.

Email away to Netgem, thanks. :smashin:
 
Tried moving my box around a little and it didn't seem to make a lot of difference (may be +/-1 on the quality/strength). Also my quality was back up to >70% on all channels lats night so I guess the poor reception the night before was down to weather. Maybe I do need to upgrade my aerial/cable after all.

I did notice on BBC1 last night that now and again I would get "glitches" in the bottom portion of the display - incidentally where the info bar comes up. Not sure if this is a feature or just a reception problem (seems strange it is always in the same area).

Also when surfing the web and bringing up the channel list only the top part of the list is displayed!

Also when dialling up my ISP and you hear the dial tone and the dialup starting, it is very very noisy - always manages to connect though!

Still impressed overall though.

PS: What are "Channel 14", "Channel 15"? They have been tuned in but are blank. Also "ntl" appears to be blank. What are channels 701, 702, 703.

PPS: Is there a shortcut to the URL bar page when already on a page? It is very long-winded to have to go via the menu route if you want to go to a different site.
 
Originally posted by Tenex
Advice appreciated

Advices found on other forum (from Pascal)
- check that you are using the cable that came with your I-Player
- check that your TV cable (aerial) is correctly shielded
- check that the I-Player is switched on (the tuner needs to be electrically powered, or the quality of your analogue signal will be a little bit faded)
 
Originally posted by lucien
Advices found on other forum (from Pascal)
- check that you are using the cable that came with your I-Player
- check that your TV cable (aerial) is correctly shielded
- check that the I-Player is switched on (the tuner needs to be electrically powered, or the quality of your analogue signal will be a little bit faded)

- I am using the I-player supplied SCART cable.

- do you mean from the outlet jack inside? The outside cable from the aerial is standard coax - I'll check to find a label of some sort.

- well if it isn't switched on or there wouldn't be a digital picture - or do I misunderstand your point? Do you mean the I-player has to be plugged in AND powered on even to receive an analogue signal?

Thanks
 
Originally posted by jase the space
I did notice on BBC1 last night that now and again I would get "glitches" in the bottom portion of the display - incidentally where the info bar comes up. Not sure if this is a feature or just a reception problem (seems strange it is always in the same area).

I get this too and wouldn't mind knowing if this is a problem with all DTT boxes, or just the I-Player



PS: What are "Channel 14", "Channel 15"? They have been tuned in but are blank. Also "ntl" appears to be blank. What are channels 701, 702, 703.

As far as I can tell, channels 701, 702 & 703 are the extra channels the BBC use when, for example, they do Wimbledon and give you a choice of 4 different matches, so if you call up the special Wimbledon menu and select the third or fourth tennis match, you'll actually be taken to one of the 7xx channels (the 2nd match will probably be the one on BBC2 if they're using that at the time).

Not sure about 14 & 15, they may do the same thing as the 7xx's for ITV or Channel 4, but I've seen anything use this (and I also hardly ever watch ITV, so I'm unlilkey to find out)
 
Originally posted by Tenex
- I am using the I-player supplied SCART cable.

I wouldn't think the SCART you are using would make that much difference compared to the cables taking the signal in... I doubt the supplied one is going to be much better than the boxed ones that come with your VCR or DVD player. (Personally though, I'm using THOR SCART's as I've found them pretty good)


- do you mean from the outlet jack inside? The outside cable from the aerial is standard coax - I'll check to find a label of some sort.

The cable you're using between the I-Player and the wall aerial socket could well make a bit of a difference, but I'd have thought you'd have to have a pretty poor cable to seriously hamper digital pictures. The cable run from the aerial to the sockets would probably make more difference.



- well if it isn't switched on or there wouldn't be a digital picture - or do I misunderstand your point? Do you mean the I-player has to be plugged in AND powered on even to receive an analogue signal?

I think when it's in standby it actually gives a boost to the signal, as I've noticed an improvement in analogue picture quality when the I-Player is in the loop and switched on, as opposed to being in the loop and switched off.
 
I did read somewhere on Netgem site that there will be a slight loss of analogue reception via loop-through if the i-Player is off.
 

The latest video from AVForums

TV Buying Guide - Which TV Is Best For You?
Subscribe to our YouTube channel
Back
Top Bottom