Magnum Dynalab ST-2 vertical omnidirectional FM antenna

[sood_spice]

I have a Harmon Kardon AVR 335 for which I had paid Rs. 40,000. (Ouch!)
The surround processor got damaged a year back and the amp was lying dead. I bought a Magnum Dynalab ST-2 vertical omnidirectional FM antenna after much researchand I got a wonderful surprise. The reception is perfect and now I am able to use my AVR as a music source! Man this is fantastic! I've been waiting for this to come along for years! Woohoo!

 

[vinod_david]

Good to hear that.

 

[gobble]

I have a Harmon Kardon AVR 335 for which I had paid Rs. 40,000. (Ouch!)
The surround processor got damaged a year back and the amp was lying dead. I bought a Magnum Dynalab ST-2 vertical omnidirectional FM antenna after much researchand I got a wonderful surprise. The reception is perfect and now I am able to use my AVR as a music source! Man this is fantastic! I've been waiting for this to come along for years! Woohoo!

Dont you think same could have been achieved with any other FM antenna ?

How much more expensive is the premium brand over others? I have been eyeing the FM tuners like a lecher :licklips: but they are out of reach financially

Cheers

 

[buswal]

hi,

what is the price and where it is available?

Do they sell active short wave radio antenna also?

cheers,

 

[anm]

avr becomes music source with an FM antenna? Sounds like khul ja simsim. Pls kindly explain more.

I have a Harmon Kardon AVR 335 for which I had paid Rs. 40,000. (Ouch!)
The surround processor got damaged a year back and the amp was lying dead. I bought a Magnum Dynalab ST-2 vertical omnidirectional FM antenna after much researchand I got a wonderful surprise. The reception is perfect and now I am able to use my AVR as a music source! Man this is fantastic! I've been waiting for this to come along for years! Woohoo!

 

[sood_spice]

@gobble

I was recommended this antenna by a friend in USA. He was very sure that this antenna would work in India. I did a lot of study and was convinced when I read about it @
http://www(dot)gcaudio(dot)com/resources/howtos/antenna(dot)html

The above link categorically states thata a multi-element outdoor antenna on a rotor is usually the best answer, but in many cases not a viable option. The next best bet is the Magnum-Dynalab ST-2 half wave omnidirectional antenna, which can be mounted outdoors or in an attic.

I guess they were right!

<How much more expensive is the premium brand over others?>

Apparently Magnum Dynalab is the only company that make this design of antenna. On their website they said it was made out of 17-7 Ph stainless steel. I searched the net for what this was and learnt it is a special alloy used for aerospace applications.
So hey, it's special. Plus it's oddly sexy too! I couldn't care less for the price. Worth it, man! Just google and see.

<I have been eyeing the FM tuners like a lecher [Licklips] but they are out of reach financially [Embarrassment] >

You need not buy a new tuner. I plugged it into my existing AVR.

 

[sood_spice]

@buswal

<what is the price and where it is available?>

I got it from Magnum Dynalab India distributor. The dealer is listed on their website. It cost Rs. 9999 including tax.

<Do they sell active short wave radio antenna also?>

I think they do only FM radio products. But am not sure. Check!

 

[sood_spice]

@anm

My AVR wasn't receiving FM signal but after attaching the antenna the reception/play back was just like a CDs'! I need not have a CD player or iPod now. I listen to my music on FM.

 

[unleash_me]

This is an excellent product. A while back we did mention it here.

Apparently Magnum Dynalab is the only company that make this design of antenna.

Not sure about this statement. Godar FM-DXR1000 has been claiming much more than ST2 at half the price. Might be worth checking it out.

 

[anm]

sorry for the analogy - but this sound like snake oil - use of aerospace alloy in toilet paper won't make it special, but rub me in a very painful way.

 

[gobble]

sorry for the analogy - but this sound like snake oil - use of aerospace alloy in toilet paper won't make it special, but rub me in a very painful way.

I agree. We need to take some product differentiators with a pinch of salt.

 

[sood_spice]

@unleash me

I did check up on the Godar before buying. The claims are hopeless. The ST-2 is perfectly tuned for receiving FM/ AM signals. Godar FM-DXR1000 supposedly works for shortwave and goodness knows what else and therefore can never be accurate for the FM band i.e. 88MHz to 108 MHz. Moreover the Godar antenna is telescopic which means its tuning will vary with the amount it is extended. God forbid a pigeon were to sit on it. I will keep running to the terrace to re-extend!

 

[sood_spice]

@anm and gobble

I asked myself the same question. However when I contacted a guy in Kerala who is an expert on antennas I was informed that weather has an effect on metal which in turn alters its receiving characteristics! Equally important is the wind factor. The aerospace alloy remains constant under extreme hot and cold conditions as well as allows the antenna to flex but still retain its original position.

 

[sood_spice]

@anm

Metals have different conductivity values and the alloy used for the ST-2 effortlessly passes the signal to the receiver. 'Space shuttle antenna' is doing a good job.

Money well spent!

 

[hemantwaghe]

@anm

My AVR wasn't receiving FM signal but after attaching the antenna the reception/play back was just like a CDs'! I need not have a CD player or iPod now. I listen to my music on FM.

FM better than Cd's?Wow..

Either this is miracle device or you have not heard cd's on decent setup...hyeah:hyeah:hyeah:

Anyone know bandwith of FM in india vis a vis CD?

 

[gopib]

@anm and gobble

I asked myself the same question. However when I contacted a guy in Kerala who is an expert on antennas I was informed that weather has an effect on metal which in turn alters its receiving characteristics! Equally important is the wind factor. The aerospace alloy remains constant under extreme hot and cold conditions as well as allows the antenna to flex but still retain its original position.

Hi,

I agree with this. After having lived in Chennai (sea coast, humidity) and managed SWL antenna, I can vouch for the disastrous effects of climate on
metal antenna components. Bangalore, where I live now, is different on
the same parameters...

Cheers

 

[buswal]

@buswal

<what is the price and where it is available?>

I got it from Magnum Dynalab India distributor. The dealer is listed on their website. It cost Rs. 9999 including tax.

<Do they sell active short wave radio antenna also?>

I think they do only FM radio products. But am not sure. Check!

thanks dude, 10 k for FM antenna is beyond my budget. I had requested my ham friend to homebrew an antenna for around 1 k.

cheers,

 

[buswal]

I am going for this fm antenna (homebrewed)- courtesy vu3nsh.


High Gain FM Antenna
(Single Quad Loop for FM Radio DXing)
by N.S.HARISANKAR - VU3NSH
Connect this 69 year old exotic Antenna and enjoy your FM band DXing.

* Type : Self Resonant Loop, 1 Lambda
* Gain : More than a Dipole (1.4 dB+)
* B/W : 88 MHz. to 108 MHz.
* Noise : Very Low
* Impedance : 125 Ohms
* Polarization : Vertical

FM Antenna

The quad antenna have a gain of 1.4 dB over a dipole and also operate over a relatively wide frequency. Quad antenna dipole to form 1/4 lambda each side makes a square. American Radio Amateur (HAM) Clarence C. Moore, W9LZX developed this system in 1939 for the Missionary Radio Station HCJB at Quito of Ecuadaor (South America). The altitude of the station was over 10,000 feet in Andes. The station was operated in 25 m band SW with TX power of 10 KW. The band width of a single dipole is quite narrow. The quad loop is having high gain and less corona discharges etc. The half lambda folded dipole impedance is 288 Ohms (300 Ohms) and this quad loop is having 125 Ohms feed impedance. Due to low impedance of the quad, there is no need of any matching, for a general FM receiver system.

Connecting a folded dipole (gain : 2.14 dB, 1.45 m long and 300 Ohms) to a FM receiver of 75 Ohms input, without any matching, its efficiency becomes to 65% (VSWR-4) and a 125 Ohms quad at 75 Ohms receiver without matching it will get 95% efficiency (VSWR-1.66) with an extra gain of 1.4 dB over a folded dipole. Due to this 3.54 dB gain from a quad loop there will be a terrific FM Radio reception. Using a split dipole, having 75 Ohms feed impedance, there will be correct match of 75 Ohms FM receiver system. But one of the element will be isolated and it makes static and lightning problems. if we ground the cable braid (shield), the entire quad or foled dipole antenna system get grounded and it avoid the threat from static or lightning effects.

FM Radio allocation in India is from 88 MHz to 108 MHz. So the mid frequency is 98 MHz. The equation for getting the wave length of the conductor is (300 x 0.95) / 98 MHz. i.e. 2.908163 meters. If we divide this value by 4 we can get the Quarter Lambda length. i.e. 72.70 cm, we can take it as 73 cm or 74 cm. Due to skin effect of VHF frequency the element should be a tube having more than 4 mm dia or use 3/8th tube for getting good efficiency.
Connection To Radio

 

[anuragn]

Hi buswal,
Do you have any antenna design for indoor use that you can share?
The quad antenna you have described above is obviously an outdoor one. Since I live in a multi-storied apartment, it is not possible to use any outdoor antenna.
Basically I am also looking for a good antenna for use with my denon avr, but cannot afford...actually cannot digest investing a 10 grand just for an antenna:sad:

 

[buswal]

hi,

You may like to try this:-

Cut a length of 300-ohm flat twin-lead cable that is 4 feet, 7 inches long. Strip the insulation from each end of the wire so that each lead has 3/4 inch of bare wire. Twist together the two wire leads on each end of the cable. Apply your soldering iron to each of these connections, and apply solder to make a solid joint.


One of the leads should be cut at the halfway point.

Cut one of the leads of the cable with your wire cutters halfway along the length of the 300-ohm cable. Strip the insulation back so that you have 1/2 inch of bare wire on either side of the cut.


Take the end of your RG-6 cable that doesn't have a connector (cut off one of the connectors if both ends do) and strip the insulation back so that you have 1/2 inch of bare wire exposed for both leads.


Solder the leads of your RG-6 cable to the bare wires in the 300-ohm twin lead.


Plug the RG-6 cable's connector into the "antenna" jack of your receiver. Tune in a station, and experiment with placement of the 300-ohm twin lead section until you get the best reception. The antenna will work best when the 300-ohm twin lead is stretched out to its maximum distance.

cheers,