View Full Version : amp output change

buffalo soldier
12-21-2015, 09:22 AM
I have a straight 6 pill (2879's) I drive this with a Galaxy 919 with dual finals.
radio keys about 1 watt swing about 60 (rat shack meter).
Problem is , it keys around 200 then swings to 850 or so. This goes into a Wilson 5000
mag mount.
I hard mounted a 102 steel whip and spring, but now it only swing 500 watts. Got new 213 coax
2 six foot jumpers and 18ft to antenna. I can see my rat shack meter being wrong, but 300 watts or more difference? Please advise. Box is a 6 pill Gator built. Swr's flat on both antennas.

12-21-2015, 01:28 PM
You need to raise your dead key to at least 10 watts. Pep wattage is fine. Don't expect large numbers!! It's not all about watts!! Keep it clean and mean and get your dead key up to make the amp key up at about 1/4 the total output. It may take up to 10-15 watts. Maybe not. This is dead key out of the radio. And to perform this you'll need a dummy load to increase dead key power as the antenna won't give a true reading

12-21-2015, 01:51 PM
And also might want to reverse the swing mod as well as I bet it looks like shizz on a scope! JMHO. Good day!!

12-21-2015, 02:34 PM
You need to make sure the vswr on the Wilson antenna is not rising with power. Sounds as if it may be with the inflated numbers. 5-600 watts is what should be seen. Maybe a bit more if driven hard. Also be advised that running a 6 pill amp into a mag mount antenna can be a recipe for disaster if all is not set just about perfect!! Just some food for thought.

12-21-2015, 02:35 PM
You really need an antenna analyzer to tell you the entire story and then at that point you can continue forward. And also antenna should be tuned without any amps inline. JMHO.

buffalo soldier
12-22-2015, 12:22 AM
Put predator 10 k, got good swr's seeing 5-600 watts, and good dx checks, Thanks.

12-23-2015, 06:25 AM
Glad you got it sorted. Remember that VSWR isn't the only factor when tuning an antenna correctly unless it has a matching coil for 50ohms built into it, the impedance and reactance can be off and it can still have a low VSWR. Thus the need for an antenna analyzer with either a 1/2 wave tuned length of coax for set freq of whatever you're choice is. 27.205 is middle of CB band. Or connect direct to the feedpoint of the antenna with a barrel connector. This will give you a true reading of the antennas R and X values as well as VSWR when you use an analyzer. If you are just measuring for lowest VSWR, then all that is needed is a good known SWR/power meter. I think you have it handled though so let it be!! It's just some food for though if you really plan on getting into the hobby, get yourself an antenna analyzer. They are worth every penny when you are tuning antennas. And also don't forget to tune in an area that is wide open and free of any obstructions for at least 50-75ft in all directions, keep all doors closed, and keep people and other cars away from your vehicle as well.
Then there is bonding of all the vehicle panels as well as the exhaust to frame.
At any rate, again glad you got it resolved. Have fun and keep an eye on the amps temp and monitor VSWR as often as possible. Just a quick check never hurts. Have fun.