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reception problems

MartinOnline said:
Thanks for the information. I think your reported strengths are "average" rather than "belting".
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I don't know what Emley Moor used to use but Sheffield used to use 21, 24, 27 and 31 and aerials used to be highly tuned to that range. I couldn't get Channel 5 (mid range here) until my aerial was changed. With a portable aerial upstairs on the PC there was no problem.

I still reckon a small portable aerial in a window pointing at Sheffield would better those signal strength figures!

bixieupnorth: does your aerial have to be at that height? Would it be possible to fit a small wall mounted one at a lower height or are there obstructions? You might be able to fit one yourself using the existing cable.
 
bixieupnorth, the fact that you receive a good signal from a single vertical element (a monopole, if it does not have a plastic blob in the middle) with no reflector or parasitic elements means that the signal strength from Sheffield is very good. It will be reduced on a lower floor where the signal is blocked by other buildings, but that's why a test is required.

[Before I moved to Sheffield I lived close (~10miles) to a main transmitter and could easily receive using a stubby monopole antenna on a wire mesh in-tray basket to feed the USB DVB-T tuner attached to my PC.]

As recommended by Mike0001, a reasonable unamplified directional indoor antenna would probably serve you best and save further expenditure on your outside antenna. Something like this: http://www.amazon.co.uk/Lloytron-Pa...cs-accessories&ie=UTF8&qid=1390989146&sr=1-11. It must be able to rotate the elements to point upwards like your existing indoor antenna - some don't.

Martin
 
MartinOnline said:
[Before I moved to Sheffield I lived close (~10miles) to a main transmitter and could easily receive using a stubby monopole antenna on a wire mesh in-tray basket to feed the USB DVB-T tuner attached to my PC.]
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AKA a wet piece of string

MartinOnline said:
http://www.amazon.co.uk/Lloytron-Pa...cs-accessories&ie=UTF8&qid=1390989146&sr=1-11
Click to expand...
That's more what I would expect of an indoor aerial. Forget the things that look like a car radio aerial.
 
but the aerial man said what i have already is performing a great job, i dont see the need to put a different aerial on the outside of the house, or clutter up the place with an unsightly indoor aerial when the one we have is doing the job its paid to do!

or are you all expecting another dramatic loss of signal soon?
 
bixieupnorth, your own experiences have shown you that (a) your existing installation is temperamental; (b) your aerial installer made recommendations that were dubious and you had to correct his actions and (c) your signal strengths are average.​
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All the people here are trying to help you end up with the best and most reliable reception. Both Mike0001 and I are very local, we know what great reception you should be getting.​
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Just take it one step at a time and prove us wrong.​
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BH, A wet piece of string; I must try that one day. Need to work out the right lengths, number of elements, spacings and will have to go for vertical polarisation, for ease of use. :)​

Martin
 
BH said:
'Scuse me, but isn't this the same chap who said you don't need a booster, and yet you had to put it back none-the-less?
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Strange you should say that BH, that's pretty much my line of thought also.
@Martin. The wet bit of string just works in a high signal area. You don't have to ponce around with lengths, directors or reflectors or anything like that, you just need to keep it damp. If it doesn't work, get a proper aerial.
 
bixieupnorth said:
but the aerial man said what i have already is performing a great job, i dont see the need to put a different aerial on the outside of the house, or clutter up the place with an unsightly indoor aerial when the one we have is doing the job its paid to do!

or are you all expecting another dramatic loss of signal soon?
Click to expand...


Yes. Particularly if this snow continues.

We are only trying to help you, but if you prefer us not to then I, for one, will stop.
 
i'm assuming that everything is weather related, and he also informed me that they had been doing some tinkering at the transmitter recently, i imagine he was trying to save me money, i get a great picture from the current set up, maybe sheffield signal would be stronger, but i cant see the quality being any better, and i'd be £80 down on the deal, could be a lot more as he said we may require scaffolding, due to the 4 storey drop from our chimney stack!

i assume he knew what he was talking about, i imagine he didnt check the reception/signal on all muxes, so when i rescanned after he left then it hadnt pulled in the lower strength muxes ie 51/52 and the new HD one.

he merely told me what he recorded on that day, maybe it will drop out again, maybe it wont, time will tell. i didnt want to sound ungrateful mike0001, and i dont think i did looking at my posts, and i want you all to keep helping me, and any others, who are less technically minded that your good selves

i'll quickly go and look at the strengths on the sheff muxes and report back, and maybe even try the indoor aerial

cheers
 
plus the strengths only dropped AFTER had i had changed all the cables, when he left it all appeared well, perhaps i hadnt connected everything as tightly as they should be?
 
sheffield muxes results, but its absolutely shocking weather, raining and blowing a gale!!

21 27 100
24 20 10
25 25 50-80 fluctuating
39 21 10
42 0 0
45 28 20

too dark to test the indoor one, but will try over weekend if i get the time
 
I was in Cardiff yesterday, with a few minutes to kill, and happened to look at the TV aerials on the roofs. Bear in mind this is line-of-sight to Wenvoe (250kW) 8 miles away, "wet piece of string" territory.

Given the numbers of aerials per chimney, the local tradesmen do a roaring trade fitting an aerial per room rather than one aerial and distribution. Also a good number of aerials/masts show wind damage (pointing all over the shop) and probably still achieve reception. One aerial I noticed in particular was a high gain X-element "digital" jobbie (talk about overkill, even before DSO). A fair population (maybe even the majority) are pointing at Mendip. Some don't look as if they are pointing at Wenvoe or Mendip!

I'll bung up a photo when I get the chance.
 
right then, i taken the indoor car aerial type down and plugged it directly into the samsung smarttv, this was its first ever tuning, its picked up 79 TV channels, i selected region as sheffield, the hd pictures appear perfect, however channels such as dave and 4+1 appear a bit blocky. when i laid the aerial on its side the HD pictures went blocky or froze

hope some of you can draw a conclusion from that?? i cant find anywhere to check the signal strengths on the tv's menu i'm afraid

cheers
 
was thinking of upgrading my booster/splitter as the one i have now is so flimsy (this one http://www.amazon.co.uk/Philex-27813HS-4-Way-Signal-Booster/dp/B0026IANHE/ref=pd_cp_ce_0 )


i thought this one looks ok? and has decent reviews

http://www.amazon.co.uk/Cables-ALL-Amplifier-Distribution-Digital/dp/B00904UZCK/ref=sr_1_2?s=electronics&ie=UTF8&qid=1391185694&sr=1-2&keywords=booster splitter aerial

or this one, as i have owned one for all products in the past and been pleased with them

http://www.amazon.co.uk/ONE-FOR-Amp...6070&sr=1-30&keywords=booster+splitter+aerial
 
bixieupnorth, thank you very much for continuing this conversation. You have provided significant information.

As Mike0001 explained previously, for maximum signal strength your antenna's elements have to be pointed Horizontal for Emley Moor and Vertical for Sheffield.

Your outside antenna is horizontal and is matched to Emley Moor, thus, as expected, it receives a lower signal level from Sheffield - but the strength of the Sheffield Transmitter is high enough to force its way in, but not good enough to give you a stable signal. That would only come if you rotated the outside antenna so its elements were pointed upwards. [I can understand that this the least attractive solution.]

I note that you experimented with the indoor car aerial type without any amplification and received a level of signal sufficient to produce a picture. The aerial points upwards so receives maximum signal from Sheffield. By laying it horizontal you create a mismatch and the signal strength reduces significantly leading to blocky and frozen pictures.

*** Before you spend any more money could you just try connecting this aerial to your amplifier and onto your Humax and report the signal and quality levels on the Sheffield Multiplexes. ***

[Manufacturers "measure" signal strength in different ways so you must use the same box.]

Without clear specifications for all the amplifiers it is difficult to make a recommendation. On a surface level your existing amplifier and your first choice have the same level of amplification; the second choice increases that. It may work.

If you are happy with your current set-up and a decision to replace your amplifier then go ahead.

If you provide one more set of results, I can offer my best list of options.

Martin
 
thanks for advice once more you two, i'll have a look at the strengths with indoor aerial plugged into the amplifier when i get a chance and report back

but it does sound like the sheffield signal coming thru a correctly alligned aerial is indeed the way forward. when we get the house painted next and the scaffolding is up then i'll bite the bullet and get one installed, should be in the early part of the summer i think

in the mean time, my fingers remain crossed, clear day today so will just write down todays figures for your digestion

cheers
 
todays sheffield muxes with a clear blue sky

21 29 100
24 10 10
25 27 90
39 22 10
42 0 0
45 30 10-40 fluctuating

so not a huge amount of difference considering the fair weather

is there a simple explanation why some muxes fare less well than others, whys 42 not picking up anything??
 
Having been up into my loft today and looked at my 4-way distributon amplifier it turns out to be this one:

http://www.amazon.co.uk/Philex-2782...58312&sr=1-4&keywords=philex+aerial+amplifier

This gives a gain of 10.5db for each output. My indoor aerial, pointed towards Emley Moor, plugs directly into it so there is minimal signal reduction due to cable loss before the amplifier.

Just checking, bixieupnorth, but are those the latest figures for (a) the indoor aerial through the amplifier or (b) using your external aerial?


Let me try to answer the question about the variability of detection, assuming that the Transmitter sends out the same signal strength across all the MUX frequencies. Note that all the variabilities mentioned below can be minor but they all add up.

1. The signals reduce as they travel out from the Transmitter and the frequencies are reduced differently as the pass through the air, clouds, trees, buildings, people, etc

2. The signals are reflected by objects and, depending on where the receiving antenna is, the reflections will increase or decease the unreflected signal.

3. The Receiving Aerial does not give out the same signal voltage for the same received RF signal across all the frequencies - most have a hump around a particular frequency.

4. The cable reduces the aerial signal voltage and this reduction is dependent on the frequency - the variation being dependent on the type of cable, its condition (age, water ingress, quality), the cable-run length etc.

5. Connectors reduce the signal strength, again dependent on the number and quality of connection.

6. The Humax's tuner is not perfect and will not detect/amplify/process the signal equally across all frequencies.

7. The Signal Strength "Meter" logic may be frequency-dependent and will have a minimum detection level.

One more specific and great variability is the case of receiving a vertically-polarised signal (ie from Sheffield) using one oriented to receive horizontally-polarised signal (ie from Emley Moor). This "cross-polar" ability of an aerial is much more complicated than the normal "co-polar".

Hope that explains the issue simply.

I think you are right to look to re-orient your aerial - you probably do not need another aerial just rotate this one.

If you hit problems then a cheap indoor aerial would probably tide you over.

Good luck.

Martin
 
MartinOnline said:
Having been up into my loft today and looked at my 4-way distributon amplifier it turns out to be this one:

http://www.amazon.co.uk/Philex-27820R-4-way-Aerial-Amplifier/dp/B00828AA2K/ref=sr_1_4?s=electronics&ie=UTF8&qid=1391358312&sr=1-4&keywords=philex aerial amplifier

This gives a gain of 10.5db for each output. My indoor aerial, pointed towards Emley Moor, plugs directly into it so there is minimal signal reduction due to cable loss before the amplifier.
Click to expand...

Same as mine, Martin, though mine is behind the TV.

There is also this one, which is cheaper, and contains a 4G filter:

http://www.amazon.co.uk/SLx-27820HSG-Output-Distribution-Amplifier/dp/B00DCVX2I6/

I thought it only boosted the signal at each output back to the original strength, but you are right. The last one is a 12dB boost.

I can't recommend the plug-in boosters from Philex. I tried one before Sheffield was boosted and it did nothing to the signal or quality, even at 1 mile line-of-sight.
 
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