Cat Cdma Antenna

[bpolky]

I have been all over trying to find an external antenna for my Novatel 760. CAT suggested I contact ThailandCDMA and M2K wireless. A WARNING!!! Do not go anywhere near these guys! After paying up front I went through 4 weeks of "it will be there tomorrow" and "delayed by red shirts" and "I am on an island" and "I will put through a refund". Finally (after 4 weeks of lies) I was told to go to the M2K shop and they would hand it over personally, they refunded my money and wanted to give it to me personally to apologise for their "bad business"..... When I arrived at the agreed time they didn't turn up and the staff had no idea what I was talking about.

So I still do not have an external antenna!

I am even having trouble sourcing one from Bangkok as no-one has answered any of my emails requesting availability.

At the moment it looks like I will have to buy something in from the USA on Ebay.

Has anybody got any ideas?

[ThaiLife]

Hi, when I bought my CAT CDMA USB modem ( MC727 ) from the local CAT office they said that I could get an external roof antenna from them, but it had to come from a shop some where near khon kaen , this is what the antenna looked like ..

and this is what the label said on the box ...

and this is what it looks like installed ( the bottom antenna is for my mobile Dtac phone )

I also bought from CAT the small '' pigtail'' cable that connects the external roof antenna coaxial to the USB modem, but after using this small cable I noticed that it seemed to be coming loose when plugged in, I found out that in fact the CAT supplied

small cable was in fact the wrong one,

This below is a shot of the small '' pigtail '' cable .....

This below is a shot of the Two different pigtail plugs , which as you can see are different

I managed with the help of a poster here, order the correct pigtail cable from eBay .

to connect the external antenna coaxial to the small pigtail cable I had to use an adapter shown below ....

as for buying an external antenna here in Thailand , as the CAT shop buy their antennas from a shop in khon kaen , they may be available in other parts of Thailand , here's a few links to try ...

http://www.siammastershop.com/index.php/cPath/471_379

http://www.bangkokwireless.net/blaithaishop/

http://www.phuket.me/

http://www.antennashop.com.sg/index.php?ro...ory&path=81

Sorry I can't at the moment point you in the right direction to buy an external antenna , if I come across a Thai supplier I will of course let you know ..

TL

[fremmel]

I bought my external antenna at CAT when I signed up for the low speed CDMA. It gave me a pretty good signal so I didn't think anything about it. Then I started reading some of the posts here about CDMA antennas and found that the correct coax is 50 ohm. Checking mine it's just RG-6U 75 ohm TV coax. So, when you do find your antenna, check the coax that's supplied with it and try to get them to give you the right one.

[bpolky]

Thanks for the detailed post. Unfortunately I have already tried the Bangkok Wireless option (have not responded to emails) and the SiamMasterShop does not list any antennas for this equipment. I will try going back to the CAT CDMA shop in Phuket Town again and see if a different person gives me a different answer!

Bruce

[bpolky]

Thanks for that Fremmel. Can you tell me if the CDMA office you mentioned was in Phuket Town or somewhere else? If it was Phuket Town, do you remember who you dealt with?

Thanks

Bruce.

I bought my external antenna at CAT when I signed up for the low speed CDMA. It gave me a pretty good signal so I didn't think anything about it. Then I started reading some of the posts here about CDMA antennas and found that the correct coax is 50 ohm. Checking mine it's just RG-6U 75 ohm TV coax. So, when you do find your antenna, check the coax that's supplied with it and try to get them to give you the right one.

[fremmel]

This was in Udon. But the antenna, and box as best I recall from 1 1/2 years ago, look just like the one ThaiLife posted. I just noticed from another post he made here that he had to replace his coax because it came with 75 ohm too. So that maybe standard in the antenna you get at CAT.

[bpolky]

After all the searching, I finallyfound someone at CAT CDMA shop in Phuket town who knew what I was talking about. They ordered an antenna for me the same as the ones mentioned on this topic. It cost about 3,500 baht and arrived a week later. I built a basic 5 meter mast to mount the antenna on, making it so I could turn the whole mast from the base to test all directions. The result? Nothing. I get better signal with the modem alone that I do with the external antenna plugged in. I have tried pointing the antenna in every direction and every orientation and the result is the same. I have a friend with some test equipment coming over soon, so we will see if that tells us anything.

BUT>>>>

I tried a different approach. Instead of putting the antenna at the top of the mast, I bought a couple of 'Active' USB cables (the ones with the little amplifier in them so that you do not get signal loss) and put the modem at the end of these. That gave me twenty metres of USB cable. I then hoisted the modem up the mast I created and use the USB cables to get the signal back to my computer. At 5 metres above the ground I got much improved signal and my upload and download speed doubled.

So now there is a bucket at the top of the mast to create a rain shield, and a rope that I can use to get the modem up and down if I have to take it with me anywhere. That has given me at least a basic reliable connection. I tens to get about 20kb/s both upload and download now, and rarely get a disconnection.

Maybe this is a cheaper and better solution that using the antennas.

[samuijimmy]

What you might try, is getting a 3 foot USB lead with what I call a "lady lady" usb adapter (the stores understood that term when I was looking for one....

& hang your modem near a window.... works well for me.... (cheap way to try & see if it helps, perhaps a 100 baht or so) ...

I had my MC 727 in Krabi a week or two back it worked fine as it has in Songkhla & other places I have traveled with it in Thailand... if you are in close range of Microwave tower. ... 2-3 Kms.... surprised you are not in Phuket!

I have an antenna (same as pictured) from my old phone modem, sitting around, but don't have the Coaxial cable connector.... but know one of the posters here found one on ebay...

I've asked a my local Samui CAT office about an adapter a couple of times, but "no have" ... But then I find my connections pretty good.... 98% of the time, so really don't need the aerial anymore.

If you are interested in Aerial, would sell, if you can find the connector! (PM me if interested)

[Dirty80s]

Hi, when I bought my CAT CDMA USB modem ( MC727 ) from the local CAT office they said that I could get an external roof antenna from them, but it had to come from a shop some where near khon kaen , this is what the antenna looked like ..

Hi Interesting post. I have some questions to you hoping you might be able to answer.

Ive got the exact same Yagi antenna as you. AND i got the 70 ohm coaxial cable too.

Where did you get your 50 ohm Coaxial cable ? And which CAT shop did you go to ? I live in Khon Kaen.

[phallang]

All you guys going for this antenna beware:

It has a frequency range of 850-980 MHz, so optimal frequency is around 915 MHz.

CAT CDMA's system is using Rx: 859.64 ~ 893.37MHz. Tx: 824.64 ~ 848.37MHz

This means that you'll probably are better of using a clothes hanger than this antenna which is totally unsuitable for CAT CDMA use...

[4evermaat]

All you guys going for this antenna beware:

It has a frequency range of 850-980 MHz, so optimal frequency is around 915 MHz.

CAT CDMA's system is using Rx: 859.64 ~ 893.37MHz. Tx: 824.64 ~ 848.37MHz

This means that you'll probably are better of using a clothes hanger than this antenna which is totally unsuitable for CAT CDMA use...

Maybe this signal booster may be what you want:

"To cover 800/1900 you will also need the YX545 SOHO. This unit will cover the 800/1900 MHz frequency bands that CAT is broadcasting in. I have attached our manual for further information."

an email reply from www.wi-ex.com

Hope this helps someone.