Sierra Wireless 250u data card and amplifier compatibility

[Dan Rupnow]

Recently, my trusty Sierra 595u data card kicked the bucket, so I upgraded to a Sierra 250u card. I really like the 250u, but the only problem I have is when I connect my antenna and "Rockies" amplifier that I got from Maximum Signal to it. The 595u worked great with that antenna and amplifier, but when I connect the 250u to it, the 250u's signal plummets, and it disconnects. I have tried it many times in different geographic locations with the same result every time. The carrier is Sprint, and yes, I am plugging into the correct 3g antenna port on the 250u. I am wondering if anyone else out there uses a Sierra 250u card, and if you have had any problems with it. Thanks in advance!

 

[Gordon Spencer]

That amplifier works fine with that card on 3G not 4G ( different frequencies ) Takes a different antenna adapter cable . Use of your old cable on that card can damage it !

 

[Dan Rupnow]

Gordon, I am assuming you are talking about the cable that goes between the amplifier and the card? I bought a new one of those from you guys at Max Signal as soon as I got my 250u card, so that can't be the problem. And yes I am using 3G, not 4G.

 

[Jim Parsons]

I had the same issue and after racking my brain trying to figure it out, I realized that I had blown the fuze in my Rockies amp...Popped a new one in an had full bars once again. The little green power light on the amp is hard to see if you are in a brightly lit place.

 

[Dan Rupnow]

I don't think the fuse is my issue either, cause my little green power light was on too. Simply connecting the amp doesn't cause a problem. The problem happens when I power up the amp, then the signal goes wacky, and the card disconnects.

 

[Gordon Spencer]

make sure mag mount antenna is on at least an 8 x 8 metal ground plane ( not aluminum or stainless steel ) only time signal will go wacky is if it is not . The amplifier either works or does not work . They do not go wacky . Remember powering up without having everything connected first can fry an amplifier.

 

[Andy Jackson]

Remember powering up without having everything connected first can fry an amplifier.

Is this a maybe or it will for sure?

 

[Gordon Spencer]

Probably will , maybe you get lucky . But why try it.

Is this a maybe or it will for sure?

 

[Mark Blue]

I had the same issue and after racking my brain trying to figure it out, I realized that I had blown the fuze in my Rockies amp...Popped a new one in an had full bars once again. The little green power light on the amp is hard to see if you are in a brightly lit place.

This is what I was thinking when I read the first post this morning as I ran into this during the 2008 chase season and Gordon helped me fix it. It's worth a check if nothing else. It's a 2 or 3 amp old style glass fuse in the tip of the DC adapter plug. I always keep a box full in my chasing kit just in case it blows when I least expect it.

Even though I don't think the fuse issue is the problem here, it just seems weird for the signal to go whacky as soon as you connect the amp. I've never had that happen before and definitely hope it never does!

 

[Dan Rupnow]

The antenna has always been located on the metal trunk lid of my car. There is a plastic spoiler that is right next to the antenna, but I don't see how that would matter because the antenna always worked great in that exact same spot with my old 595u card. Just for the heck of it though, I will try moving the antenna to a different spot on the car to see if that seems to fix the problem.

 

[Andy Jackson]

Probably will , maybe you get lucky . But why try it.

Just trying to remember if I may have done this in the past. I ran a test tonight and it seems to be working so we are good to go.

 

[Dan Rupnow]

Well, as an update, today I hooked up my Rockies amp to my Sierra 250u card, and drove around to a few different local locations to test it out. Of course it made me look like a liar, and performed flawlessly the whole time. I again had the antenna mounted on the metal trunk lid of my car where I always do. Perhaps it was just an isolated incident that I had over the summer when I was having problems. For the record, I was in an area of low signal and roaming at that time. As a backup though, I have bought an external car mounted antenna that is for use without an amplifier. Obviously, using an amp is better, but I am wondering how effective an external magnetic mount antenna without an amp is. Anyone have experience using ampless antennas?