Fiddling with setup for better speed, should I stop ?

ac439 · EVDO Fledgling Joined: 20 Nov 2007 Posts: 20

My paint can 595U modem setup has quit working reliably lately. I noticed there has been a lot of hopping towers (away from my preferred tower).

I have a few things and ideas on hand ---- a 16" wok, a MMDS grid antenna at 2.5GHz, a DISH network 20" sat dish and a homemade biquad scaled to 1.9Ghz.

I first tried it with the "wok". I roughly located the focal point and "duck taped" the 595U on it. Got better signal but still hopping towers a lot. All of a sudden, I remember I read somewhere that the built in antenna usually is horizontal. But the 3G signal is vertical polarized. I then placed the 595U sideways to make the built in antenna vertical. Suddenly, I noticed a few dbs improvements and the preferred tower is locked in all the time ! RSSI could be as best as -83db and the EC/IO around -4dbm. I was able to get over 1000 down and 200-300 up. But still the wok was pointing into the forest.

Few days ago, I played around with the grid antenna. I replaced the center feed element with a wooden dowel and placed (duck taped) the modem at the focal point sideways (to get vertical polarization). Got my laptop outside and put it on a ladder 5ft above ground pointing into the forest. I got -80db RSSI and EC/IO -4 to -5 dbm. up/down at 1300/300. Preferred tower can be locked in easily.

Then I got an used Dish network off center feed sat dish. Without taking apart anything, I again "duck taped" the modem just on the feed horn facing the dish. Again, modem positioned sideways to get vertical polarization. Using a C-clamp to temporary attached the dish mount to a table inside and pointing into the forest, my RSSI is not as good as the outside grid. -85 to -93 bouncing (most of time at -88 ). But I have no problems locking into my preferred tower. Up down speed is the best with this setup. Highest recorded was 1800/600. Even if the RSSI went into -90s, my down/up speed still well over 1000/300.

Today, I finally built my scaled biquad and use a pigtail to connect to the modem. This setup gives me the strongest RSSI but NOT the fastest down/up speed. RSSI at -80db (sometimes -79) ec/io at -4 but down/up typically at 800/200. I am kind of puzzling with this since my ec/io is still good with better RSSI but my speed has lowered compare to the dish setup above.

I have yet to try the grid with dipole at focal point and DISH outside the house with biquad feed. But I'm wondering if I would be getting any better results. I'm pretty sure my location is giving me a few indirect paths to the tower. The forest has probably scattered the signal too. My reason being the satellite dish gives the best result even with less RSSI strength is the beam is more focus and I'm possibly eliminating other multipaths into the modem which causing signal degrading.

Any comments / suggestions ?