am/fm/vhf antenna splitter

deaglan169

hi guys just wondering what your opinion on this is i know wimo in germany sell something similar to this for 2m 145mhz but this is alot cheaper would it work with 145mhz considering it is designed for vhf marine band it only specifices vhf band.... would make for very tidy car install and save drilling

http://www.sailelectronics.co.uk/Produc ... p?Pid=9903

brownmini

deaglan169 wrote: »

something similar to this for 2m 145mhz
work with 145mhz considering it is designed for vhf marine band it only specifices vhf band....

http://www.sailelectronics.co.uk/Produc ... p?Pid=9903

The makers website is at
http://www.pacificaerials.co.nz/

Catalogue is at
http://www.pacificaerials.co.nz/site/DefaultSite/filesystem/documents/MarineAMFM07_9-11.pdf

I doubt its performance on 145 will be good.
It seems to be aimed at users of 156.

deaglan169

was thinking that alrite ahh well looks like it will be the black and decker after all:rolleyes:

brownmini

deaglan169 wrote: »

was thinking that alrite ahh well looks like it will be the black and decker after all:rolleyes:

Let's not be too hasty here.
Besides 145 MHz, is it 88-108 broadcast you want as well or Medium wave ?

brownmini

deaglan169 wrote: »

was thinking that alrite ahh well looks like it will be the black and decker after all:rolleyes:

If you are handy with a drill then
how handy with a soldering iron are you ?


see: http://www3.sympatico.ca/richard.blackman/THE_DUPLEXER.html

deaglan169

i was hopping to use my 2m antenna for fm broadcast receive also 88-108 plan was to remove current broadcast antenna and replace with 2m one i have seen a few projects on the net like the one you posted and i have no problem soldering but seems alot of hassle being honest if i could buy one great but im not too bothered so think i will drill it in

brownmini

deaglan169 wrote: »

i was hopping to use my 2m antenna for fm broadcast receive also 88-108 plan was to remove current broadcast antenna and replace with 2m one i have seen a few projects on the net like the one you posted and i have no problem soldering but seems alot of hassle being honest if i could buy one great but im not too bothered so think i will drill it in

The other option is...
Replace the existing aerial with the 2M aerial.

Then using a suitable section of bodywork, make yourself a ''bodywork aerial''.
Attach the centre of broadcast coax about 16 inches away from the attach point for the coax braid.
A suitable place would be the front grill area especially the bit where the bonnet latch, attach 8 inches either side of the centreline and use that as your broadcast aerial.
It might be a DC short circuit but at 100 MHz it isn't.

or

Just make up a dipole for 100MHz and hide it behind the front or back window trim/facia/plastic. each piece of wire, 71 cms each.
and use that as your broadcast aerial.

deaglan169

ummm not a bad idea:rolleyes: but would the 2m radio then interfer with the broadcast rx i know generally i dont have radio on and chatting on 2m at same time but my broadcast receive is poor at the minute and thats using an amplified broadcast antenna btw car is a seat leon im going to remove roof cloth later today and i will investigate your sugguestion thanks:D

watty

145Mhz is a lot closer to 100MHz than 152 .. 160MHz
Also 50W.. on 2m maybe,

You need a VERY good duplex filter to avoid frying the FM band-II radio. The Marine one will be no use.

Anything decent would have maybe 6 to 8 coils or more and associated capacitors.

Or simply have a simpler combiner and switch operated from 2m radio ACC socket to disconnect FM radio and short its input when you transmit.

The FM radio will work well enough on a decent 2m aerial as most of the car radio aerials these days are total rubbish. The issue is simply to not dump you 10W to 50W into the radio.

I have older more traditional roof car aerial. MW I can get Radio Devon (in Limerick) and Limerick 95 on Dublin side of Portloise.

In any case if you do any amount of power you want to add a relay to protect the car radio by disconnecting its aerial and shorting its input during transmit.

I put my 2m aerial at back of roof and angle car radio aerial nearly flat to reduce coupling when using 2m/70m/6m/10m (6m/10m aerial on other rear side if also in use)

deaglan169

cheers watty thanks for reply i think the wimo one is prob the best commerical made one i have seen so far im in two minds on what to do but easiest i suppose is just mount the 2m antenna infront of the car radio antenna look the tidest but unfortunately i have no way of changing the angle of my fm antenna to reduce coupling just one of those things ill have to put up with

brownmini

deaglan169 wrote: »

ummm not a bad idea:rolleyes: but would the 2m radio then interfer with the broadcast rx i know generally i dont have radio on and chatting on 2m at same time but my broadcast receive is poor at the minute and thats using an amplified broadcast antenna btw car is a seat leon im going to remove roof cloth later today and i will investigate your sugguestion thanks:D

I would go that far.
In my own car the door pillars bits come off easy enough but I'm not
that dedicated to listening to VHF broadcast radio to want to pull my
car apart.

Perhaps the changeover relay route is the best.
If the car radio is still wired the way that I remember, the blue wire
out the back has 12volts on it when the radio is switched on.
This 'was' for an electric aerial - things might have changed since.
When radio is on , relay switches aerial into car radio.
When radio off, relay relaxes and connects aerial to 2m radio.

At this stage, you're damned if you do, damned if you don't.
And god help you if you slide across the paintwork when drilling
that second hole!!!

deaglan169

oh i hope i dont slide across the paintwork:eek: only disadvantage i can see to the relay and i may be wrong here is that if its connected the car stereo i wont have receive on 2m which is a big problem in my eyes although i may be wrong so i think to avoid headaches drill hole fit antenna and separate cable run to 2m radio