Weird issue where i get better reception with the aerial not conencted to the wall plate!

phoenix_rising

Standard Member
I have a slightly strange issue where my TV gets a stronger signal when my aerial is not plugged into the f-type cable hanging out the back of the TV! The aerial cable is aroun 8m so must be acting as a reasonable passive aerial!

I'm a bit stumped as i'm using a brand new screened f-type module, which i beleve is wired up fine (aerial core is in the middle pin, shielding cage is installed over it and the shielding of the cable is only touching the housing of the module.

I've rewired the socket 4 times and had the same result every time.

The wall plate is connected to the main aerial via a splitter.

Anyone have any ideas?
 

BigA1

Well-known Member
Water in the cable to the socket? Stands to reason if everything is fine until you attach it to the plate and the plate is fine... it must be after that point...?

Does the cable run externally at all? Where is the ariel?

Just guessing
 

TJT1

Member
Sounds strange, especially as the plugs/sockets are F Type. F Types are usually associated with satellite dish/tuners.
Bypass the splitter as a test.
 

Gavtech

Administrator
@phoenix_rising

Can you clarify please - Are you receiving Terrestrial transmissions (Freeview) through an aerial, or satellite transmissions via a dish?
 

Rodders53

Distinguished Member
Has the cable been crushed or kinked? Those screened (modular or standard) plates need extra deep wall-boxes and cable entry from below, ideally.

Remove the 4dB attenuation of the splitter, direct connect the aerial to the downlead to that room, if possible? Any different?

Ensure splitter ins and outs are observed correctly. (TV Y-splitters have a male plug for input.) Is the splitter a powered (amplified) one?
Pictures and/or make and model numbers of the aerial and splitter with cables may help?

Where is the aerial (outside on roof) or in loft or...?

A more precise location (in London?), to estimate transmitter(s) and signal levels available to you?

What signal strength and quality readings does the TV report when connected to the socket and when disconnected and picking up 'directly' on the cable?
{Possibility of that relatively rare overload condition, I'm thinking, when connected properly?}
 

phoenix_rising

Standard Member
Some great info here guys, really appreciate your replies. I didn't want to overwhelm my initial post with too much info as it puts some people off... so i'm glad you guys have requested it! :)

@BigA1 - Water in the cable to the socket? Stands to reason if everything is fine until you attach it to the plate and the plate is fine... it must be after that point...?

Does the cable run externally at all? Where is the ariel?

Just guessing

> Main aerial is on top of the house and goes down to ground level where one of those passive distribution 4 way splitters is. Not sure on the correct term of that these technically are. No water that i can see in the ends, cable or boxes though that i can see.

@TJT1 - Sounds strange, especially as the plugs/sockets are F Type. F Types are usually associated with satellite dish/tuners.
Bypass the splitter as a test.

> I was advised that F-Type connectors, although used predominantly for sat installations, were a better connector that the traditional aerial connectors and generally made better contact so i went with them. I think me using the term splitter may have been incorrect. I think technically it's a 4 way distributor that was installed at the time that the aerial was installed. I cant really bypass the distributor as it's creating the aerial feed to the room. And i'd need to take a feed from this distributor to get anywhere else.

@Gavtech - Can you clarify please - Are you receiving Terrestrial transmissions (Freeview) through an aerial, or satellite transmissions via a dish?

> Sure, when i bought the house i had a load of virgin media and sat cables fed into rooms from a previous installation, i was advised that the cable was of reasonable quality and could be reused to transmit a freeview signal, so i've since had f-type connectors put on the cables and reused them installed by an aerial installer. The issues i'm having are due to me doing some house renovations and have since relocated the master bedroom aerial cable from the aerial installers location to a new location and using a wall plate as opposed to old location which was a trailing cable coming out the wall about 1m high up from the skirting board! I'm using the aerial connections for freeview via the internal digital tv tuner.

@Rodders53 -
Has the cable been crushed or kinked? Those screened (modular or standard) plates need extra deep wall-boxes and cable entry from below, ideally.
TV wall plates

> Nope not kinked that i can see.

Remove the 4dB attenuation of the splitter, direct connect the aerial to the downlead to that room, if possible? Any different?

> As mentioned above, i described this badly. No splitter of sorts just the 4 way distributor coming off the main aerial.

Ensure splitter ins and outs are observed correctly. (TV Y-splitters have a male plug for input.) Is the splitter a powered (amplified) one?
Pictures and/or make and model numbers of the aerial and splitter with cables may help?

Where is the aerial (outside on roof) or in loft or...

> On the roof.

A more precise location (in London?), to estimate transmitter(s) and signal levels available to you?

> Surrey, Kingston way.

What signal strength and quality readings does the TV report when connected to the socket and when disconnected and picking up 'directly' on the cable?
{Possibility of that relatively rare overload condition, I'm thinking, when connected properly?}

> This is an interesting one and where i was up to prior to reaching out the to forums. It's an older TV, a good 8 yrs+ I've attached a picture of the current signal strength of the TV with the aerial connected, I'd removed the aerial extension cable and it seems to have improved the signal a lot. How does the signal strength look to you in terms of attenuation? (I'll grab one with the aerial unplugged from the face plate tomorrow.

I dont want to jinx it, but it seems removing the extension and nipping and tightening the f-type connectors to the wall plate has stabilized the signal quality at "high" on the sony TV technical page (which i take with a pinch of salt.) So fingers crossed. I'll be interested to see how it holds up against the signal with no wall plate connected to see if it's still worse...
 

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Rodders53

Distinguished Member
Sounds to me like the F-plug pin was a tad short and not making full and proper contact with the socket, until fully tightened home?

The picture suggests a very high signal level to me and the AGC (gain control) is reducing things down to compensate. The TV is also having to compensate for reception errors seen (but that's normal) and there are zero un-correctable.

Do check the meter for every multiplex frequency to ensure they are all similar?

Your 4-way "distributor" is a splitter. Passive or powered/amplified? A picture of it, cover removed, would help identify.

A 4-way passive splitter loses 8dB of signal from in to out. Random Kinston postcode kt1 2qj, Wolfbane predicts 76 dBuV/m from Crystal Palace. +10dB for an aerial -8dB for split and -4dB (cable and termination losses) = 74 dB at the outlet(s).
Recommended ideal level is 45 to 65 dB.

10dB gain for an aerial may be generous, but even a small log periodic or 10 element contract will have 6dB gain. So 70dB perhaps?

Overload is a possibility, I think, if you start getting reception problems again.
 

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