Hello,
My receiver have 2 antenna ports, as usual in all receivers)))
1) AM Loop
2) FM Unbal 75om
I have one antenna - AM loop only. Can I connect it to FM port? Actually when I connect it works OK but it may also damage tuner or reception of rf may not be high quality. Please Advise.
Regards,
Turkel
My receiver have 2 antenna ports, as usual in all receivers)))
1) AM Loop
2) FM Unbal 75om
I have one antenna - AM loop only. Can I connect it to FM port? Actually when I connect it works OK but it may also damage tuner or reception of rf may not be high quality. Please Advise.
Regards,
Turkel
You won't get the best reception but it won't damage anything.
If you want better reception connect a 75 Ω FM antenna to the FM antenna input via a 75 Ω coax cable.
Tom
If you want better reception connect a 75 Ω FM antenna to the FM antenna input via a 75 Ω coax cable.
Tom
As makeshift FM antenna, is ok to use a thin wire with a length of about 75 cm.
Should I connect both Ground and Line or line is enough? As it not makes difference in gain quality when I tested.
pcan's suggestion, when connected to Line only, is sufficient in an area with good signal strength.
Alternatively, you can make a dipole using twin speaker wire, each horizontal branch 75 cm long, one connected to Line and the other to Ground.
You can separate out the screen and core of coaxial cable in a similar fashion to #6 above in order to form a dipole aerial.
It may work better if you are locating the dipole some distance away from your receiver.
It may work better if you are locating the dipole some distance away from your receiver.
The FM band is about 100MHz, ie 3 meters so a 1/4 wave is 75cm. A single dipole configuration gives an impedance of 73 Ohms, a good match for 75 Ohm coax.
https://en.wikipedia.org/wiki/Dipole_antenna
Any length of coax or other wire will have losses but allows you to move the antenna to a better position. A horizontal antenna is directional and must be set 90 degrees to the direction of the transmitter, so you may want to set the antenna vertically for an omnidirectional antenna. The FM band was established when there were only 6 TV channels, just above channel 6 and channel 7 started above FM, so a TV antenna may work well. The history of FM, Armstrong and channel 1 is a long and interesting story.
Today, FM broadcasters have added "Hybrid Digital" and "Radio Data Systems", replacing some of the bandwidth that was used for commercial "Muzak" in the past. These are intended to compete with satellite services and well supported by auto stereos but not well represented by home receivers. HD and RDS sidebands are visible using cheap SDR (Software defined Radio) USB gadgets.
https://www.amazon.com/NooElec-NESD...hvlocphy=&hvtargid=pla-4583589114701981&psc=1
https://en.wikipedia.org/wiki/Dipole_antenna
Any length of coax or other wire will have losses but allows you to move the antenna to a better position. A horizontal antenna is directional and must be set 90 degrees to the direction of the transmitter, so you may want to set the antenna vertically for an omnidirectional antenna. The FM band was established when there were only 6 TV channels, just above channel 6 and channel 7 started above FM, so a TV antenna may work well. The history of FM, Armstrong and channel 1 is a long and interesting story.
Today, FM broadcasters have added "Hybrid Digital" and "Radio Data Systems", replacing some of the bandwidth that was used for commercial "Muzak" in the past. These are intended to compete with satellite services and well supported by auto stereos but not well represented by home receivers. HD and RDS sidebands are visible using cheap SDR (Software defined Radio) USB gadgets.
https://www.amazon.com/NooElec-NESD...hvlocphy=&hvtargid=pla-4583589114701981&psc=1
If you want to geek out completely you really should add a balun to that dipole antenna. That's probably more important if you want to use the antenna for transmitting, though.
If all you want to do is to receive a local radio station all you really need is a thin piece of wire inserted into the centre conductor of the coax antenna input. Bonus points if this wire is 1/4 wavelength (so about 75 cm) long. If this doesn't give you satisfactory reception or you're trying to receive a station that's far away, you really need a proper antenna - preferably a directional one.
Tom
If all you want to do is to receive a local radio station all you really need is a thin piece of wire inserted into the centre conductor of the coax antenna input. Bonus points if this wire is 1/4 wavelength (so about 75 cm) long. If this doesn't give you satisfactory reception or you're trying to receive a station that's far away, you really need a proper antenna - preferably a directional one.
Tom
If you are in a poor FM reception spot, here is an alternative. I am not a ham or radio guy so I can't say it works better or worse than a dipole, I think it's just easier to relocate and [aim] or orient. Maybe it would be useful to get the bearing right for your preferred station, then figure out how to mount the dipole.
The dongle at the back of the receiver isn't required, I have added a LTE blocker because I am close to cell towers here.
I forgot to take a closeup of the top tension adjuster, but that's just two zip ties - one in the slot and one on the wire.
And the orientation of which corner is on top apparently matters for some stations (circular vs horizontal vs vertical polarization, but I couldn't explain it).
Here are some instructions. Not sure if this is the site I originally found, you can hunt around for a "full loop FM antenna" if it's not clear.
https://mikestechblog.com/build-an-indoor-fm-antenna-with-these-plans/
The dongle at the back of the receiver isn't required, I have added a LTE blocker because I am close to cell towers here.
I forgot to take a closeup of the top tension adjuster, but that's just two zip ties - one in the slot and one on the wire.
And the orientation of which corner is on top apparently matters for some stations (circular vs horizontal vs vertical polarization, but I couldn't explain it).
Here are some instructions. Not sure if this is the site I originally found, you can hunt around for a "full loop FM antenna" if it's not clear.
https://mikestechblog.com/build-an-indoor-fm-antenna-with-these-plans/
