396T Antenna/Connector Problems

[MysticalOS]

Recently I noticed signal degradation on my 396T, area's where there is no doubt i should be getting 5 bars of strength and I'm getting 2-3. When I looked further into it i came to find out this was being caused by the actual connection between antenna and scanner, if i loosened antenna a bit (enough to actually fit a finger nail between antenna and rim) it'd go back to 5 bars, further testing revealed that applying an SLIGHT pressure on antenna back killed signal almost completely, but slight pressure forward kept it at max. As if the connection was strong on one side but almost gone on other. I eventually found solution by using a rubber washer to maintain the finger nail gap in connector while still allowing it fit snug and not loose. I've inspected again and again and i can't find any reason why there are problems though. Metal contact is good, both antenna and connector. Nothing is stripped or anything. have never tampered or messed with it in any way...I'm hoping it's not too expensive to fix. Was kind of wondering on any input or recommendations. Have owned for a year now. Got when very first came out. Has been in uniden repair once for silk screen and audio popping distortions (they never fixed the audio problems btw, grr).

 

[pinellasfirefighter]

i hope that doesnt happen to mine..

 

[redhelmet13]

Im having the same probem - nuts!

 

[MysticalOS]

Im having the same probem - nuts!

Uh oh. I hope this isn't a prelude to further issues to come with my scanners first birthday.

 

[pinellasfirefighter]

not a problem with mine yet.. are you guys changing the antennas out alot?

 

[slicerwizard]

applying an SLIGHT pressure on antenna back killed signal almost completely, but slight pressure forward kept it at max.

Pushing the antenna forward shortens the distance between the bottom of the jack's center pin and the RF board. You need to find someone who knows which end of a soldering iron is hot and get them to resolder the antenna connection, 'cuz it's broken. They'll also need a small Phillips screwdriver for the 12 screws.

 

[MysticalOS]

not a problem with mine yet.. are you guys changing the antennas out alot?

Yes. But i always felt I was being careful about it. But careful still has wear and tear over a year of switching 6 times a day I suppose. (stock to vhf vehicle antenna,vehicle VHF antenna to UHF-low vehicle antenna, UHF-low vehicle antenna back to stock, then the reverse for the long drive back home) since i primarily monitor a millitary base TRS on 406-411mhz and the surrounding counties conventionall to and from the base while traveling....

 

[MysticalOS]

Pushing the antenna forward shortens the distance between the bottom of the jack's center pin and the RF board. You need to find someone who knows which end of a soldering iron is hot and get them to resolder the antenna connection, 'cuz it's broken. They'll also need a small Phillips screwdriver for the 12 screws.

and if I can't? what would uniden charge to fix this, how to prevent from happening again? I've been trying to find a switch to reduce number of switches when traveling. IE plugging in my 3 antenna's into a switch that plugs into scanner where i can just activate antenna on the fly when traveling between an 800mhz system, 400mhz or 150mhz which are 3 antenna's i got on car..

 

[ofd8001]

You may consider trying to manufacture a 3-4" lead-in for your antenna connection. Have the SMA male on one end, and for the other end whatever connection you use the most. When you make your antenna swaps, connect the antenna cable to the end of the manufactured lead. That way you are not un-connecting and re-connecting to the antenna fitting on the scanner. May save some wear and tear on the scanner's antenna connector.

Granted this may cause you some signal degradation, but it sounds like you signal done got degraded the other way.

I'd be tempted to send it back to Uniden and see if it is a warranty repair matter. After getting it fixed, then try the lead-in cable deal.

 

[cristisphoto]

Try the BNC ....

Why don't you all just try using the Included BNC connector
I haven't noticed ANY difference myself OTHER than the usual different antenna for Diffrent ranges

OF course, I havn't really looked for it Either
SO I wiil defintly Check that out and,
(If all goes as planned ),repot back ASAP


Regrads,
Crista

FYI
i am a bit weary of SMA as I am always araid of stripping it
BNC you just push in and twistl:lol:

 

[MysticalOS]

I actually have noticed difference between BNC connector adapter and equivilent sma antenna. Someone explained to me it's not so much the loss in the connector but the way it alters the length of the antenna which effects the field and reception of antenna. Course I'm certainly no expert on these things but it kind of made sense to me. heh..

 

[slicerwizard]

and if I can't? what would uniden charge to fix this, how to prevent from happening again?

Why don't you ask in the GA forum here? You'll probably find someone local willing to help with a simple soldering job. Barring that, find a local radio shop or neighbour. Look for a house with big antennas.

Once it's fixed properly, you shouldn't have any more problems. You could also try not tightening the antennas so hard.

 

[mancow]

It's all just BS getting in your head.

There isn't enoug loss with the BNC adapter to even notice it there, unless it's flat broken. That is highly doubtful due to the simplicity and ruggedness of the piece.


I would use the BNC and be done with it.

 

[MysticalOS]

Would anyone know where to find or how to make an antenna switch, one that would have 3 sma inputs and one sma output cable that wo uld go to scanner, and some means of pressing a button or a switch to choose between the 3 external antenna's on the fly...preventing me from having to switch the cable goingt to scanner itself nearly as much..

 

[MysticalOS]

I figured out the exact cause now. It is not the connection on inside of radio nor would soldering fix it. I found the problem is inside the pine whole on top. The 2 (or maybe s upposed to be 3, mine only has 2 now) metal pieces are loose on inside and actually sliding around, i can even see them slide out some when i left antenna up. Seems these metal connectors are what whore out, so no matter how many times i unscrewed and screwed gentle and slow, it was never the connector that had the wear and tear. But really tine c shaped metal slide in's on inside of antenna hole itself that became lose. Go figure. I'll be sending off to uniden for this. I am curious though if i lost one of the pins. Two are still in there and it seems there is a slight ammount of un metal coverd area, that maybe a 3rd one resided in at one point that i never noticed fell out one day which could have been start of real noticable signal drop...They have gotten so lose at this point unless I am right next to signal source, i get nothing, and right next to s ignal source i get like 1 signal bar. :\ Fortunately my second 396 is do to arrive any day. So i can use that until my first one get's repaired and returned for my dual wielding pleasure

 

[slicerwizard]

Man, where have you been pimping your poor scanner? If it's been out whoring, it's no surprise it caught something nasty and now its um, plumbing is falling off. Time to see a specialist...

 

[MysticalOS]

From what i can guess, the connector on one of my antenna's has a bigger package than the other antenna's. The pin is thicker. So i guess you can say my scanner was stretch and became lose and couldn't handle small anymore lol...