How can I get EVDO Rev A without an antenna but not with one

jon8105 · EVDO Heavy User Joined: 05 Dec 2006 Posts: 147

I have an AC595 card that can get Rev A, normally around -100dB, with speeds around 600Kbps down and 100Kbps up with latency averaging around 130ms.

How is it that if I attach an omni antenna on top of my roof I can no longer get EVDO? I thought that the omni would increase all the 800Mhz and 1900Mhz signals it receives, which should therefore give me a better EVDO signal. But instead it increases my 1xRTT and doesn't allow me to get EVDO. Even if I lock the card to only allow EVDO it just doesn't let me connect at all.

Also, without the antenna my speeds are consistent and I have never been disconnected. I am usually on the interent three to four hours a day and without the antenna I run good. But I would like better speeds, so can someone tell me why the omni will not work. I am thinking about getting a yagi, but I would like to know what is causing the omni antenna from increasing my signal.

note: I have tried this on two computers with two omni antennas and get the same result. I have even went on the roof with the laptop and still nothing with the antenna attached.

kc_fan · Posted: Fri Jul 06, 2007 2:49 am Post subject: Issues with the Omni attatched

Just currious about your set up, with the omni on the roof are you using a extension cable to get it to the roof? If you are how long is the cable and which type of cable is it. I am wondering if you are using a long cable run if you may be loosing whatever gain the omni may have in loss from the coax run.

Another thing that you might check is if you are getting a good connection on your card to the external antenna jack, I have heard of issues with the jack on some cards. My brother is using the omni with the 12 ft of coax it came with and had to use the 3 watt amp to see a big diffrence.

Thanks,

Mike

jon8105 · EVDO Heavy User Joined: 05 Dec 2006 Posts: 147

I am only using the cable that came with the omni, and I don't really need that much. My window is on the second floor so the antenna is only about 5 feet above me on the roof.

I have used the amp with the card and that didn't help EVDO.

However, my 1xRTT signal goes from about -90dB to -82dB with the omnis, so I know that they are working with my card. Last night I was on the internet for about 5 hours and my EVDO Rev A signal, with no antenna, stayed at an average of -95dB, and sometimes went down to -92dB.

I have ordered a yagi and it should be here Monday or Tuesday, so I will report back with my results. But if someone could please explain why an omni antenna would increase my 1xRTT but decrease my EVDO Rev A to the point that I can't connect to EVDO. If the omni is dual band, which they are, it makes no sense(at least to me Smile

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kc_fan · Posted: Sat Jul 07, 2007 10:50 pm Post subject: EVDO

The only thing I can think of is maybe it is increasing the 1xrtt so much that the signal for EVDO is then beeing drowned out and it looks at it like it is background noise.

I know at my brothers the Trucker Omni does appear to be better at helping his 1xrtt then the EVDO, it does increase both for him but the 1xrtt is much more improved than the EVDO signal. So even though it is a dual band, maybe it performs better/is tunned better for 1xrtt signal gain.

I would still expect at least some mprovment for your EVDO with the omni, so that's why I think maybe the 1xrtt signal is so much stronger that it is over-riding any improvment you would see for the evdo.

Have you tried to set it to connect EVDO only and assuming it connects run speed tests both with and without the omni connected to see if it speeds up the connection with the omni vs without? Maybe the signal it is showing for EVDO with the omni attatched is not a true reading?

Thanks,

Mike

kc_fan

Sorry, I just re-read your first post and you have answered most of what I asked, one more ? I did not see this answered, with the omni attatched, what -db does it show the EVDO signal, or does it show at all? I saw that with out it is around -90 to -95db.

Thanks,

Mike

jon8105 · EVDO Heavy User Joined: 05 Dec 2006 Posts: 147

With the omni antenna attached it doesn't show anything for EVDO. Hopefully the yagi I am getting on Tuesday will work, but I would still like to know what the problem with the non-directional antennas is.

kc_fan · Posted: Wed Jul 11, 2007 10:01 pm Post subject: Omni

Ok, one more question, I see you have tried two Omni's and 2 laptops, do you have access to someone else that has EVDO but a diffrent evdo card/adapter that you could try the omni on? I am wondering if it is something with the combination of your AC595 card and the Omni.

Thanks,

Mike