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I believe the right most antenna is a mono-pole helical "rubber ducky" (please correct if wrong).

But what type of antenna is on the left? It is terminated with a U.FL connector (not shown) and the center pin connects to a thin copper braid covered in a transparent insulator. The metal spiral connects to the shield and is conductive but I'm not sure what type of metal it is.

Both antennas have had their rubber moldings removed. They are both made by Wellshow but I can't find details of the left one. I do know they are both made for 900/1800MHz.

enter image description here

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  • \$\begingroup\$ If the inner wire of the left-hand antenna is joined to the helical wire at the top-end, it's probably a plain-old dipole antenna, though I'm not sure what effect the bottom half of the dipole being helical would have. \$\endgroup\$ Commented Apr 5, 2013 at 6:40
  • \$\begingroup\$ Sorry the pictures not clear - its not connected at the top. \$\endgroup\$
    – Mark B
    Commented Apr 5, 2013 at 6:51
  • \$\begingroup\$ No clue what type it is, then. Sorry \$\endgroup\$ Commented Apr 5, 2013 at 7:02
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    \$\begingroup\$ Please crop and scale your image to a more appropriate size. This will probably improve view quality too. \$\endgroup\$
    – jippie
    Commented Apr 5, 2013 at 20:10

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As far as I can see that's a Helical Antenna on the left too. Helical Antennas are directional antennas.

See Wiki for further informations.

However it's a special helical antenna. Do to its small size they make some tricks:

A feeding method is proposed for small helical antennas with diameters of about 1/80 to 1/20 wavelength. The present feeding method consists of excitation of a helix with a total length of about 1/4 wavelength and with its lower edge grounded by an open‐ended center conductor oriented coaxially to the helix.

There's a paper about it here (whitch is the above's citation's source).

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    \$\begingroup\$ OP knows the one on the right is a helical. However, the OP is asking about the one on the left since that one slightly different. Also, it's best if you do not provide research articles since they require a paywall to view it. No one is going to pay money to go into further detail for one answer on StackExchange. \$\endgroup\$
    – user103380
    Commented Aug 8, 2018 at 20:37
  • \$\begingroup\$ @KingDuken Yes so do I. You may have a look at the abstract of the added paper. \$\endgroup\$
    – Mr.Sh4nnon
    Commented Aug 8, 2018 at 20:38
  • \$\begingroup\$ See my edit please :) \$\endgroup\$
    – user103380
    Commented Aug 8, 2018 at 20:39
  • \$\begingroup\$ Ou okay well. I see the problem. What do you suggest? Adding the complete abstract here? Guess I have to leave to link than as source. Saddly I haven't found a source like wikipedia, which provides similar information. Despite beeing an abstract, it at least answers his question: it should be a helical too \$\endgroup\$
    – Mr.Sh4nnon
    Commented Aug 8, 2018 at 20:41

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