RTE1 and RTE2 difference in signal reception

Sam Russell

I have had a strange reception problem for ch 30 and 33.

Both are broadcast from Three Rock at the same power so should be received at the same level. Well, RTE 1 is jumping all over the place with signal at 20% to 50% with quality between 0% to 50%, while RTE 2 is steady but over 50% quality with signal at 40%.

I am using a log periodic that has been at least a decade in service.

I have had to resort to a home made aerial made from a coat hanger that gives 100% Sig and 100% Quality. (I will attach the design later when I get the time - I have been using the design for nearly a decade in my bedroom as I do not have a cable reaching there yet).

I think the problem centres on corrosion in some of the connections, but it does not make sense. Any ideas as to wht two ajacent frequencies should behave so differently.

marclt

If you’re receiving on an alternative “aerial” with no issues at all, it’s probably an issue with your original set up. If it’s temporary, possibly co-channel interference but if it’s long term something needs replacing - the aerial itself or the cabling.

Sam Russell

I tried a different telly with similar result. I have not solved it entirely, but I suspect the terminals are possibly corroded. I have a combiner that mixes the satellite and Saorview signals into the feed cable to both tellies.

I still do not understand why one mux is misbehaving.

Antenna

If you disconnect the satellite receiver (leaving just the terrestrial connected so ensuring LNB powered Off) - does it change the situation?

dxhound2005

I don't know if it is a quirk in my equipment (Doctor HD combi box, chimney aerial up about 40 years), or whether other people can replicate this. I get different Quality readings from the different transmitters at each location. I think the clue is probably in the term Maximum Power. I have no way of knowing what actual power is being transmitted on each frequency. Then again an aerial can behave differently on different frequencies with the same power. If someone can get 100% quality on a coat hanger, there is obviously no transmitter fault.

Clermont Carn maximum 160 Kw power listed by Saorview. Channel 42 85%. Channel 45 82%.

Kippure 63 Kw. 34 52%. 35 45%.

Three Rock 63 Kw. 30 29%. 33 50%. (There is a 50 Kw transmitter at Divis on Channel 30, which may account for the low reading?). Their other two 50 Kw transmitters on 23 and 26 are both 59%

Divis 100 Kw. 21 85%. 24 75%. 27 62%.

Camlough 500 watts. 40 75%. 43 75%. 46 69%.

MBSnr

^^^

Over the last few days RTE1 from the Maghera transmitter has had periods of no signal. Our neighbour asked us if we had an issue (we have Sky) so I checked on our Saorview TV and we did as well. Both RTE1 and plus 1 no signal. Seemingly all other channels, even on the same MUX were working fine.

dxhound2005

https://www.boards.ie/discussion/comment/121142595#Comment_121142595

Look in the Lost Channels sticky at the top of the page. Although it says that the engineering works at Maghera were only on 20 September.

MBSnr

https://www.boards.ie/discussion/comment/121142735#Comment_121142735

Perhaps the first issue we saw of RTE dropping earlier in the week necessitated the engineering works on Wednesday.

Sam Russell

I am fairly convinced the problem is associated with some level of corrosion with the connectors at the aerial/satellite end. Unfortunately, it is over a decade since it was installed, and I cannot find the connectors left over from the installation. I think I would also need a special tool to release the F-type connectors.

So, I need to order them.

dxhound2005

Just continue with the coat hanger if that is getting all the stations.

Sam Russell

https://www.boards.ie/discussion/comment/121143878#Comment_121143878

I must show the design here. It works well because I am in a strong signal area.

Antenna

https://www.boards.ie/discussion/comment/121143720#Comment_121143720

Does disconnecting the satellite receiver (ensuring LNB is powered off) make any difference to the terrestrial problem?

Just in case the LNB is for some reason generating some noise on ch 33 which is strong enough to cross-over the diplexer and cause problems

" I think I would also need a special tool to release the F-type connectors."

a Size-11 spanner (3/8 inch in imperial) would help release stiff F-connectors

Sam Russell

I need a special tool that has a reach like a screw driver, rather than a spanner. A couple of suppliers have them. I might get a low cost sat finder as well as I had the wind move the dish.

Thanks for your suggestions.

Sam Russell

I have opened a new thread with the instructions for how to build an aerial for Saorview.

https://www.boards.ie/discussion/2058315422/saorview-aerial-from-coat-hanger-zero-cost

coylemj

OP, I have the same problem with an indoor UHF aerial picking up Three Rock. It's in the bedroom as a test, I have a VM digital (multiroom) box connected to the same TV. When I select the aerial as the source, RTE1 is occasionally not available while on other days, the RTE1 reception is perfect. I do a rescan every so often but it makes no difference.

I think the problem is that, by design or otherwise, the aerial is optimized for a range that includes one MUX (probably 33) and reception of the other MUX varies, depending on atmospheric conditions. You'd expect an indoor aerial to be wideband so you wouldn't get variable reception in certain parts of the spectrum but that doesn't seem to be the case here.

I disconnect and reconnect the aerial when I'm dusting and cleaning and the issue is always there. So I don't think your problem is down to corrosion but I note that you've fixed the problem with a DIY hanger aerial - well done.

dxhound2005

RTE 1 is not perfect just because you are seeing a perfect picture. That could be coming from a 60% Quality reading, and at 58% the picture would be gone. You need a better aerial set up if you are having intermittent reception.

Sam Russell

https://www.boards.ie/discussion/comment/121158976#Comment_121158976

Try and make the aerial I describe in the other thread.

coylemj

https://www.boards.ie/discussion/comment/121159686#Comment_121159686

Thanks for the advice on the DIY aerial but it's not worth my while. For starters, I don't have a soldering kit. As I mentioned above, the aerial is in the bedroom and the same TV has a VM multiroom box - the aerial is not the sole source so it's no big deal if I can't get RTE1 from Three Rock.

I really only use the aerial if I want to listen to an RTE radio channel off Saorview - saves power by not using the VM box.

Sam Russell

https://www.boards.ie/discussion/comment/121159927#Comment_121159927

You can get away without soldering - just make sure connection are made with the washer and screw. Try it and see.

The only reason I say to solder, is that after 10 years, the connections got corroded. I am sure that it will work if you try it.

dxhound2005

If it is possible to move the aerial around, there might be a location in the room where the signal peaks. Use the menus to look at the signal readings. Anyone doing changes should note the signal readings first, for a Before and After comparison.

Antenna

https://www.boards.ie/discussion/comment/121146317#Comment_121146317

Has the dish definetely moved? It could be the same issue affecting your terrestrial, perhaps water in coax (and/or water in outdoor diplexer?) or whatever seeing as you are diplexing sat and terrestrial

Sam Russell

https://www.boards.ie/discussion/comment/121167741#Comment_121167741

Yes, the dish is prone to move in high wind. It is located at a low level and tends to move down in high wind. I give it a push with a broom to raise it enough to get the signal back. I use the TV signal info to direct me (with assistance). I use Freesat, and not every station is the same. The recent move of BBC stations to be HD has required some realignment and some drop in signal strength. I use a London postcode.

The difference between RTE1 and RTE2 is new, and is due, I think, to corrosion in the F type connectors. Now the current installation is in place over a decade - nearly 15 years, I think. The UHF aerial feeds into a diplexer, along with the four outputs from the LNB.

I intend to redo that whole installation, perhaps moving the UHF aerial to a higher location to give a stronger signal strength.

Perhaps I might get it to match my coat hanger model. :)

ShaneOC

https://www.boards.ie/discussion/comment/121159927#Comment_121159927

I have a similar issue with RTE 1 signal dropping from 98% to 0-3%. I have identified that the signal only drops if the Apple TV 4K is powered on. If it is powered off then the signal on RTE 1 is perfect. RTE 2 is unaffected (98% always). Aerial is in the attic.

I wonder if you see the signal drop if you power off the VM box?

Slightly Kwackers

https://www.boards.ie/discussion/2058314853/rte1-and-rte2-difference-in-signal-reception

No I don't know why signals that close are causing the problem, but you can get reflections from external items or even corroded cable connections that add destructively to the signal.

I had exactly the problem you describe, it had two sources, The first is the trees that come very close to the aerial and if I dont cut them for a couple of years RTE2 goes with a low signal and high error rate.

Last year I had the same problem and cutting the fairly short tree didn't cure it on that occasion. It was an "F" connector plus joiner I had put in in place of a masthead amp. Water somehow got under the self amalgamating tape and corroded the braid.

Sam Russell

I think I have certainly found one culprit which turned out to be corroded braid on a coat hanger aerial I have used for a decade. It then started on the household log periodic which was compounded by corrosion on a small co-ax cable, but persisted after that was sorted.

So now I must revue my aerial and satellite setup, which is also a bit over a decade old.