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Cobra 18 WX ST II (don’t laugh)

I received a 6 to 4 pin mic adaptor because I wanted to try my Cobra power mic. Stock President mic is ok but mmmm....could be better.

I installed the mic and did some mic checks with my son on a Uniden HH cb. He said the Cobra power mic sounded much much better!! Cleaner speech. With the mic gain on max I can go up to #6 before it distorts. He said sounded a little scratchy past that. I would transmit on one and then the other and the Cobra was a winner! I had a small convo with another station about 10 miles away and my audio was clean and mean. One of the features I like on the President mic is the channel selector but I will take better audio any ole day!!!

Having good on-air checks is the bees knees.

Now switch places with him.

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I received a 6 to 4 pin mic adaptor because I wanted to try my Cobra power mic. Stock President mic is ok but mmmm....could be better.

I installed the mic and did some mic checks with my son on a Uniden HH cb. He said the Cobra power mic sounded much much better!! Cleaner speech. With the mic gain on max I can go up to #6 before it distorts. He said sounded a little scratchy past that. I would transmit on one and then the other and the Cobra was a winner! I had a small convo with another station about 10 miles away and my audio was clean and mean. One of the features I like on the President mic is the channel selector but I will take better audio any ole day!!!
That's good stuff right there, finding the right combination of gear. That's the fun part. I would be tempted to try a D104M6B on that radio if the Cobra got good reports. But at the same time, if you got something that works great, don't touch a thing! Run it like that for a while, then when you get the itch for something different, try the D104M6B.
Chris
 
I had to raise modulation on SSB to 11-12w due to President having it set low at 6w. Also set RF power at 4.5...again President had to set to 3.5w These numbers is what’s showing on my meter so there is some error in actual but more or less it’s set now.

Quick question...I have the radio set at 2.5w on AM since I have the KL203. But since SSB has no carrier, can I turn up the radio to 4w with amp when on SSB?
 
16 Watts PEP on SSB, (anecdotally) you could see 4 Watts of "forward swing" on an average reading Watt meter.

<on a dummy load ;)> If no o'scope to observe quality of output single you can ask for an audio report, or observe on (SDR) or nearby radio, if the sound is too compressed or distorted I'd say you are over-driving the amp.

16 Watts PEP should be okay, I'd think... I'd run it at 12 Watts to help the amp run cooler. The advertising material says 4 watts AM, but I found about half of that is where I can comfortably run mine... 'Else it got really hot and flat topping was observed on 'scope.
 
I have it set around 2.5w for am and it swings 11-12w pep. With the amp it will pep at 125w and deadkeys around 25w.

On SSB full radio power..4.5w or so with the amp on it reads 150w pep.

I am not trying to squeeze any crazy watts out of the radio. Just trying to get it to where it should have been from the factory.
 
I received a Sirio Performer 5000 and 145PL mag mount few weeks back. The antenna had the wrong base for my application. It wasn’t the PL base. So a quick call and a correct base was sent. Great service to correct their error!!

I installed it mid week. The coax on the mount is short. It’s about 12-13 feet. It barely made the connection to the KL203 under the seat. No way that coax would fit to the dash if I didn’t have the 203. I have the coax running to the rear tailgate, behind the tail light and into the opening inside.

Well I attached the connector and “attempted” to set the antenna for the least SWR. Higher SWR than I had expected. More than my 6’ Skipshooter on the rear bracket. Lower number on ch40 than ch1. Ok let’s raise the whip. Well whip maxed out and still high SWR on ch1. Especially when amp was turned on. Jumped to 2.5!!

I started thinking that this antenna works on 10m/11m. Seems like the closer I got to the 10m frequencies the better the SWR got. To me the coax is too short for 11m. Ok..I am not starting a coax length doesn’t matter argument. These are just my findings.

I added 6ft of Jefa and it helped a little. Still SWR too high. I added a 3ft jumper for a total of 9 extra feet. Total of 21 ft to the amp from the antenna. That did the trick!!! SWR was beautiful barefoot and with amp on!! Getting around 1.5 amp on across the all channels. Maybe I am tricking the meter with long coax and more loss but it works. I checked with my power meter and I was great! No power loss.

I had some contacts and I am getting good results. Not too far...around 15 miles. Nothing going on for 11m these last few days around here. RX is better too! Around 1s unit. Little better than the Skipshooter on the corner of vehicle. The antenna is center on top of truck so should transmit without being so directional since it’s on top.

I am still playing/reviewing the Sirio. I like that I can have a roof mount that can be folded down pretty low for the lowest parking structures.

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Nice, although you had some issues with tuning it looks like you received great customer service. Would you mind sharing where you made the buy? Could help some of us determine where to buy if we go that route.
 
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