Omega Owners Forum
Omega Help Area => Omega Electrical and Audio Help => Topic started by: tigers_gonads on 25 September 2013, 22:46:35
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http://www.ebay.co.uk/itm/Connects2-CTDAB-2-Universal-DAB-Digital-Radio-Tuner-for-all-FM-car-stereo-radios-/190790935692?pt=UK_In_Car_Technology&hash=item2c6c06a48c
I have already fitted the ipod unit from the same manufature with no problems at all by splicing it inline into the ariel wire in the drivers side footwell.
Looking for dab in the car now :-\
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Whats the reception like with the glass mounted aerial.
I had poor reception when using the Highway unit with the provided glass aerial but when replaced with a Hirchman as advised it was trully brilliant
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The problem with any device that goes in line with the existing aerial lead is one of signal quality.
Whilst the device you have added may work well enough, the extra joints and inline circuitry is often just enough to prevent the very poor quality radio signal from the car antenna to actually reach the radio.
Used with an external aerial should be fine, but an internal or amplified aerial, and you may have signal strength issues when listening to your radio.
;)
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The problem with any device that goes in line with the existing aerial lead is one of signal quality.
Whilst the device you have added may work well enough, the extra joints and inline circuitry is often just enough to prevent the very poor quality radio signal from the car antenna to actually reach the radio.
Used with an external aerial should be fine, but an internal or amplified aerial, and you may have signal strength issues when listening to your radio.
;)
Is that why I loose most of the fm signal for the other radio channels when the ipod is switched on ? I've found that as soon as I turn the Ipod off, it returns as good as new or is this down to the inline transmitter drowning out the weaker signal from the roof ariel ?
I did try out the various frequencies and settled on 88.0 mhz.
The ipod unit is powered from the switched live at the back of the head unit with a tiny inline fuse ;)
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Whats the reception like with the glass mounted aerial.
I had poor reception when using the Highway unit with the provided glass aerial but when replaced with a Hirchman as advised it was trully brilliant
Just using the ipod one at the moment amba.
No aeriel, its hardired inline
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Agree with what Dave has said and it was on his excellent advise that I bought the Hirschamn aerial that has been fitted in place of the existing stubby aerial on my M/f Elite for well over a year now.
Signal strength is very good and only rarely do I loose the signal this being only when in the "outback"
Best £50,s worth of entertainment I have spent out on for many years
External aerial is the way to go with a direct lead from aerial to the unit.
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External aerial is the way to go with a direct lead from aerial to the unit.
You would never put a TV aerial in the loft and expect a watchable picture
And yet you would all argue that the INTERNAL aerial in the Omega is sufficient
It isn`t :-X
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Is that why I loose most of the fm signal for the other radio channels when the ipod is switched on ? I've found that as soon as I turn the Ipod off, it returns as good as new or is this down to the inline transmitter drowning out the weaker signal from the roof ariel ?
I did try out the various frequencies and settled on 88.0 mhz.
The ipod unit is powered from the switched live at the back of the head unit with a tiny inline fuse ;)
Thats because the transmiter in the Fm device is crap and is kicking out way more than the frequency it should.
Add in that the signal output will also be high so the RF demod AGC will wind right down reducing the signal strength on the other channels.
I ahev to say, I never had issues with signal strength for the radio on any of the Omegas though.
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As some know on here, I have a Harmon a kardon fm modulator hard wired into the fm aerial on the back of the 2015.
There's a clear difference in reception with it.
1 fine before it was connected (obviously)
2 roughly a 20% loss in signal strength when the device is off.
3 roughly 50% signal loss when the device is on. (Which doesn't matter if your listening to the device)
%loss is a guess based on radio stations available! just yo give an idea.
So there will be a loss of fm signal.
Iirc TB said expect 30% loss of signal per connection/join in the aerial
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External aerial is the way to go with a direct lead from aerial to the unit.
You would never put a TV aerial in the loft and expect a watchable picture
And yet you would all argue that the INTERNAL aerial in the Omega is sufficient
It isn`t :-X
I'm a fair way from our TV transmitter, in Oxford (the one that famously caught fire when "testing" for DSO, so spent several months on a smaller tower at reduced power), and I have an indoor aerial. It just needs to be suitably sized ::)
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As some know on here, I have a Harmon a kardon fm modulator hard wired into the fm aerial on the back of the 2015.
There's a clear difference in reception with it.
1 fine before it was connected (obviously)
2 roughly a 20% loss in signal strength when the device is off.
3 roughly 50% signal loss when the device is on. (Which doesn't matter if your listening to the device)
%loss is a guess based on radio stations available! just yo give an idea.
So there will be a loss of fm signal.
Iirc TB said expect 30% loss of signal per connection/join in the aerial
3db from memory...
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Nah, coax socket of half decent quality will have an insertion loss of of 0.2-0.4dB
An active device if well designed similar......the 'well designed' bit being the key.
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External aerial is the way to go with a direct lead from aerial to the unit.
You would never put a TV aerial in the loft and expect a watchable picture
And yet you would all argue that the INTERNAL aerial in the Omega is sufficient
It isn`t :-X
I'm a fair way from our TV transmitter, in Oxford (the one that famously caught fire when "testing" for DSO, so spent several months on a smaller tower at reduced power), and I have an indoor aerial. It just needs to be suitably sized ::)
Indoor one works fine for me, too.. Practically in line of sight from Rowridge (but a fair distance away!).
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While they chat amongst themselves about stuff nobody understands.
Accept. The fm signal will suffer.
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Now how many times have I had posts deleted due to thread drift :-X :-X :-X
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While they chat amongst themselves about stuff nobody understands.
Accept. The fm signal will suffer.
Er no, if the device in question was/is designed to any level of quality then the FM signal will suffer practicaly nothing.......
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While they chat amongst themselves about stuff nobody understands.
Accept. The fm signal will suffer.
Er no, if the device in question was/is designed to any level of quality then the FM signal will suffer practicaly nothing.......
But they're invariably not. So it will :P
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While they chat amongst themselves about stuff nobody understands.
Accept. The fm signal will suffer.
Er no, if the device in question was/is designed to any level of quality then the FM signal will suffer practicaly nothing.......
Can you expand on that Mark because i'm genuinly interested :)
Are you saying that the transmitter is pushing out that much power regardless of what frequency it is set to that it is swamping the other frequencys ?
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The first stage that the FM signal goes through is a pre-amp with auto gain control, next stage will be a mixer to reduce the received signal from its 100Mhz spectrum to an intermediate frequency. These will be in the metal screened can associated with the antenna connection.
So if the injected FM signal is many times higher than that of the received signal, the PLL section will lower the gain of the preamp and consequentaly the received FM stations.
Whats more, the FM transmitters are horrific quality so they will be far from broadcast standard and will emit a wide spectrum of frequencies which will mask radio stations close in the frequency range due to bleedover.
Stereo is also questionable as the FM setup is actualy for a mono channel (Left plus right), the stereo is produced by transmitting a further audio channel with L-R using AM supressed carrier at 38Khz above the base frequenc plus a pilot tone at 19Khz.
There is also pre-emphasis on the audio signal (they boost the amplitude of the high frequency audio before transmission and then reduce it in the reciever to improve the signal to noise ratio).
A simple low cost solution by the designers would have been to shut off the internal transmitter after a period of no audio input.
Similarly, the cost of a decent RF stage would run into the few pence to reduce losses in the device (I suspect that actualy there are very few losses and that the main issues is the AGC)
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While they chat amongst themselves about stuff nobody understands.
Accept. The fm signal will suffer.
Er no, if the device in question was/is designed to any level of quality then the FM signal will suffer practicaly nothing.......
But they're invariably not. So it will :P
If anyone finds an emulator that doesn't weaken the Fm signal, do tell. :)
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While they chat amongst themselves about stuff nobody understands.
Accept. The fm signal will suffer.
Er no, if the device in question was/is designed to any level of quality then the FM signal will suffer practicaly nothing.......
But they're invariably not. So it will :P
If anyone finds an emulator that doesn't weaken the Fm signal, do tell. :)
Your uphill gardener has an aux out IIRC? I may possibly have a solution, as I've done on the MV6, but needs further development on the NCDC. Let me get it working on mine (TBE) first, job for those winter days... ...once I've got one of my scopes replaced.
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While they chat amongst themselves about stuff nobody understands.
Accept. The fm signal will suffer.
Er no, if the device in question was/is designed to any level of quality then the FM signal will suffer practicaly nothing.......
But they're invariably not. So it will :P
If anyone finds an emulator that doesn't weaken the Fm signal, do tell. :)
Your uphill gardener has an aux out IIRC? I may possibly have a solution, as I've done on the MV6, but needs further development on the NCDC. Let me get it working on mine (TBE) first, job for those winter days... ...once I've got one of my scopes replaced.
Yeah audio out, map on page 5. :y
http://www.harmankardon.com/resources/Brands/harmankardon/Products/productrelateddocuments/en-us/ownersmanual/dp1_us_revb_f.pdf