MMDS Set-up Complete Beginner

I think I have noticed a serious flaw of those Yagi aerials.
I have seen in a couple of instances what I believe to be serious galvanic corrosion on the rods.
The rods when left exposed to the harsh Irish climate for only a few months has caused them to become covered in a white or black powder and caused signal degradation in rain.
The rods obviously arent coated in a corrosion resistant substance similar to those manufactured by Cal Amp.
The spacing between the washers is ~2.5cm ,which means the rods are designed for a wavelength of 3Ghz instead of 2.5Ghz.
Ideally the spacing should be 3cm.
In the vast majority of reception cases this will not make much of a difference to the signal strength.
However coupled with the corrosion problems this makes the aerials unstable in any sort of rain .
I have had a Cal Amp Yagi running for over 9 months and its rod is perfect ,as day one.
Has anyone encountered similar symptoms ?

 

the white powder you are talking about is aluminum oxide
Aluminum is very reactive chemically but it resists corrosion by the self-protecting continuous thin layer of oxidation which forms quickly on the nascent aluminium surface when exposed to oxygen, water or other oxidants and prevents further corrosion.
i mean,it is normal
RAIN IS cause OF signal degradation , NOT A white powder
btw .i've ordered CAL AMP downconverter - only 32 euro (inc.delivery from states)

 

Yes the white coating is probably aluminium oxide as you said.
Let me clarify my comments.
I havent seen the white powder on the Satandcable rods I have seen it on a different manufacturers,and it seems harmless,the signal is excellent ,0 ber.
The satandcable rod after exposure is covered in a black material which definitely degrades the signal even in light rain.
Rain should not affect the signal.
As soon as a drop of rain hits the rods the signal breaks up.
I have doused water over the downconverter and the cable and it has no effect.
Only when on the rod does it affect it.
I've since replaced the rod with a different one and its perfect again,even when pouring a watering can over it.lol
I have taken the rod away for examining ,its not a pretty sight.

 

sounds like youve got it in for satandcable Fano

 

Hi anyone know the max distance ch***s mmds transmitters transmit as i will be buying a antenna that must be used within a distance of 15 miles
or are transmitters stationed in most town areas.Im living 7 miles from town thanks.

 

Check this out Chris

http://www.boards.ie/vbulletin/showthread.php?t=2055169562&referrerid=59211

 

thanks claret for your reply excellent info thanks again.

 

Not really.
I'm just curious why a few of their Yagi rods are covered in black gunk after a few months.

 

interesting, let me know how you get on

 

Well guys and girls after many hours of reading I have found out that I am in a C****s MMDS area and have recntly bought a The Box-T from Bubble Cable Boxes and was wondering does anybody know if they are auto patched before they arrive?

Thanks in advance.

 

The Box T from Bubble Cables come as plug and play - ready to go.

 

Hi all just got my box-T and bought the mmds integrated downconverter+aerial and power supply from sat and cable.The box is already set for my area with ch***s but am getting no signal i was told that this was set for a chorus aerial which may have a different frequency to the aerial i bought and may need to be set up.Could anyone please explain what i need to do for it to work with the Sat and cable aerial i bought using the box-T menu.Thanks
Chris.

 

hi chris100.

I rekon you need to add 440 to the cho*us freq in your area and set-up the box to scan on them.

eg nthell mmds dublin starts at 258. using the yagi from satancable I start scanning from 698 in 8mhz increments. does that make sense. using your original STB, if its a pace one. turn it off by pulling plug. hold channen up + down on the from of it and plug back in. this should bring you to a service menu. this will show you the freq for your area.


I'm having a problem with my Yagi. Basically it's set-up in the loft. and signal is good sometimes but choppy other times. is there a way to improve signal. I read gracem did it with tin foil. I've ask him but got no reply.....anyone help my????????

 

i did improve the signal lol ) -- got a grid 24 dbi aerial, and gave yagi to friend of my ( he is not far away to transmitter)

 

Thanks cmonks,claret08 the box i have was set up for me most of the channels range from 200Mhz-300Mhz the aerial i have is the one from sat and cable which ranges from 662Mhz-848Mhz.What i do is i went into inastallation/ manual scan i then changed the frequency to 662 and scanned. I then jump 8Mhz each time and scanned until i hit 848Mhz but i get no signal from any of them.
The settings i have are network scan is enabled (tried it disabled as well)Antenna power is set to on.
Also in the manual scan settings before i enter anything the Level bar is 0% and the quality is 0%.
All the ch***s aerials are pointing south which mine is aswell but im not getting any signal.Am i doing it correctly thanks for the help.

 

hi chris.

662 is only the starting freq of the areial.. you need to find the freq of the first transponder of chorus in your area...

do some searching on these forumns and other and you might get lucky.

 

Hi, When you mean "loft" do you mean inside the attic? dont these aerials have to be mounted outside ? Also, does the aerial need to point in a certain direction like a satelite ?

would this suffice for getting mds in cork ? http://www.satandcable.co.uk/s/product_info.php?cPath=44&products_id=83

thanks,

 

You have to start with 666mhz. First valid frequency should be 682 or 690mhz for ch*rus.

 

thanks lads will try that should i go up in 1's or 8"s as have been going up in increments of 8 for each scan thanks for all your help

 

Hi anyone any ideas as to why I have lost RTE and TV3 on C - - - - s MMDS using a eurovox TX box and also I tried a The Box T and i dot get channel names for the various stations I only get numbers I.E. 401 for RTE etc etc