PDA

View Full Version : Rm Italy swr



Chickenlittle
08-14-2018, 06:38 PM
Hey guys, I'm new to the forum.

I'm running a cobra 29lx with an Rm Italy kl200p amp. I was talking barefoot today and the antenna warning went off. I flipped the amp on and it transmitted fine.
I'm working out of town and don't have my meter so I checked with the built in swr, it's 2.3 barefoot and barely reads amplified, same with the amp bypassed.

I do have it choked down with a 24" firestick but it's been working fine all summer.

Assuming the built in swr is halfway accurate everything's fine except for the internals of the amp when it's off.

Thanks for any help in advance.

mattsowders1989
08-16-2018, 03:18 PM
Standing wave is way too high. I wouldn’t be comfortable until it’s at least a 1.3. Check whether it’s higher on 1 or 40 to determine if it’s too long or too short.


Sent from my iPhone using Tapatalk

222DBFL
08-17-2018, 07:30 AM
A 24” antenna isn’t going to be very broadband. May get VSWR down on a couple channels but that is most likely the best you’ll get. Also don’t expect VSWR to be too low with that short of an antenna. Just some food for thought.

mattsowders1989
08-17-2018, 08:30 AM
Hey 222. Been a while. Good to see your still around.


Sent from my iPhone using Tapatalk

T-I-N-Y34
08-17-2018, 11:05 AM
I ran into the same problem while hooking up my setup. I would have argued someone until I was blue in the face if I didn't figure it out on my own. The jumper coax was reading fine on a meter. but it was bad. I switched it out and my SWR's dropped from 2.5 to 1.3 with the amp on. and flat-lined 1.0 with it off. I've also had weird readings with coax and then ran the coax a different way and it cleared it up. So ya never know. But for sure open up those waves with a longer antenna and let that amp breath...lol

222DBFL
08-17-2018, 01:20 PM
Hey Matt, hope all is well your way sir!!!

mattsowders1989
08-17-2018, 01:21 PM
All is buddy. Hope all is with you


Sent from my iPhone using Tapatalk

222DBFL
08-17-2018, 03:19 PM
Also remember gents that when tuning an antenna from the beginning one should use an electrical half wave of coax. Anything other will give false readings possibly. Just some food for thought. Took me a while to understand myself. Read up antennas. There is much that can be learned. Again, just food for thought. Having an antenna analyzer also halos tremendously when it is used correctly.

mattsowders1989
08-17-2018, 07:43 PM
That’s why I make all my antennas from scratch. I know what it takes to make them all a flat 1:1 ratio. Can’t have any SWR of any kind with my home made 16 pill. Too much money in that bad boy.


Sent from my iPhone using Tapatalk

222DBFL
08-17-2018, 08:35 PM
Yep you best have all things in order before you start running lots of power. Things can get ugly very fast if not!!!

mattsowders1989
08-17-2018, 09:56 PM
Yep


Sent from my iPhone using Tapatalk

Chickenlittle
09-02-2018, 12:07 PM
I'm thinking antenna is the likely issue. I was originally running a 102" whip behind the cab, but I switched to the firestick on the front fender a couple of months ago so I could put racks on for fire wood and never switched it back. Everything worked fine with the original setup. This doesn't mean I'm going to discount the short coax, I'm going to start there first, just to be sure.