General questions about my newest acquisition

[David 379]

Good day all ,

I'm new to the forums here but wish to learn more about my radio setup and want to get the most out of it , best way to put me is I know enough to be dangerous lol.

I have a 99 Peterbilt 379 , I just installed a Stryker 955 with Cophase K40 antennas , yes the Stryker was converted to Chicken Band , and yes tuned for 11 meters. My cable is a Wilson Cophase cable and is confirmed by the radio shop to be 75 ohm , I also measured and matched both my antennas to the same length , measured that they are in the same spot on each mirror and that they have a perfect 1.5 SWR reading between 1 and 40.

With all that said I have a Volvo triaxle that has a Stryker 655 with a Stryker antenna and a horrible SWR match due to poor grounding , however my 655 sitting next to my 955 seems to recieve better than my 955 , so I'm curious if this is just an affect of the cophase and that my 655 is getting more of a 360° reception , where as I know cophase tends to be more directional , or is there something else going on I should look at ?

Also would like to learn more about what my radio is capable of since this is a whole new world compared to the 655.

Thanks in advance , and please be kind , again newbie lol

 

[9C1Driver]

Other then the 11m conversion your 955 should not need any special tuning and does not need to be "tuned for 11 meters" as you put it. Depending on who went through that radio maybe the receive is out of alignment now. I would swap radio's and check the receive and see if anything changes. Then you would know if the problem is radio or antenna related. Also if the antenna system in the Volvo is really that bad I would not key up a radio until you fix it. Mosfet radio's do not like high SWR at all and you could smoke the finals.

 

[nomadradio]

I have 'tuned' more than one Galaxy, RCI, Connex, Uniden and other "10-meter" radios to perform better on 11 meters. You can frequently tell the before-and-after difference.

A Stryker won't need this at all, in my experience.

Unless someone diddled it, turning receiver adjustments while keying the mike.

"Hey, what does that one do when you turn it? ....err, nothing." (then unkeys the mike).

Results in some receiver adjustments having "random" settings, rather than optimized settings.

In my experience Stryker sends the radio out ready to go, as far as alignment is concerned. Not so much some other (not all) brands. Not much to be gained by "tweaking" a new Stryker. An old one may have some adjustments drifted with age, but not a new one.

73

 

[David 379]

Other then the 11m conversion your 955 should not need any special tuning and does not need to be "tuned for 11 meters" as you put it. Depending on who went through that radio maybe the receive is out of alignment now. I would swap radio's and check the receive and see if anything changes. Then you would know if the problem is radio or antenna related. Also if the antenna system in the Volvo is really that bad I would not key up a radio until you fix it. Mosfet radio's do not like high SWR at all and you could smoke the finals.

The 655 has an SWR match of 3 , which in my opinion is horrible, but that's the best I could make work with the antenna placement , I will try swapping them tonight and just see if there is a difference since that is a viable idea tha k you .

 

[jdchet]

Regarding the Volvo..............how and where is the antenna mounted? Pics? I've found that the Bird Perch mounts that screw into the existing mirror bolt holes work pretty good.
https://www.bobscb.com/shop/product...vo-ALL-STAINLESS-STEEL-Mobile-Antenna-Mounts/
These can also be found in many truck stops.
While not the perfect fix, I've had the best luck with 15 feet(not 9 or 18 feet) of good coax! This stuff is really good......https://www.dxengineering.com/parts/dxe-8xdx015..........and not terribly expensive.

JD

 

[fourstringburn]

I had many Volvo trucks throughout the years and learned them well. I ran both CB and HF radios with them.

The swing arm style mirror brackets on later models are painted and are made of some kind of cheap metal and don't ground antennas. The newer Volvos have a plastic aerodynamic cover on them.

The bird perch as JDChet mentioned do work except on the passenger side. Antennas other than fiberglass whips have more wind loading and will push the bird perch loose in the counter clockwise direction while driving. It did that for me with a big coil aluminum antenna even with high strength locktite on the threads.

I had better luck using 1 1/4 mirror post brackets you can find in truckstops and running a flat braided ground strap from the antenna bracket to the same screws you would use the bird perch on. Auto part stores sell these straps in short thin ones to thick longer ones.

You'll need to run 18 ft of coax anyway just to run the length to the antennas unless you want to drill new holes.

I ran my cables along the dash and lower windshield area, dropped it down on the left corner, removed the plastic door threshold and ran the wires under that and the matting behind the drivers seat where there is a rubber gromet where some of the the cab electrical wires run.There is enough room to run your coax into that gromet to get your coax to the outside. I then ran coax up to the firewall using zip ties to keep it neat and then up to the hood shelf below the wipers and spread it across to each antenna. The hood can still close without pinching the coax and the coax will be hidden in the cab giving a neat appearance.

In the pic below you can see a tall antenna mounted on the lower bracket and see the coax coming out from the hood. You can just easily run it to the upper mirror bracket but you would be best using a larger coax like RG213 like I did because it's stiffer and wont flop around while driving. Your not likely to find 75 ohm coax in a RG8 size. I always just ran a single antenna.

The other pic shows my HF antenna and a large thick ground strap which mounts to a bolt under the hood. This shows how to run coax damage free to the outside.

No ground problems with any of my antennas!

 

[jdchet]

Yes.......screw in Bird Perch on driver's side only. The reason I said 15 feet of coax is I read somewhere that,taking coax velocity into account, it puts you closer to where you would want to be as far as 1/2 wave length, or something like that. Personal experience also factored into that, but it isn't the ideal solution similar to the 9,18 foot "rule" that's been out there for a long time.
Anyone that is having a hard time with SWR on the stock Volvo antenna system can try adding a 9 foot length of coax to the stock coax and it will help calm it down. Had to do that in one of our trucks so I could use the box stock Uniden I have.
You would certainly know more than I regarding antenna systems! I've just started learning and aggravating myself on this Cascadia! LOL!

JD

 

[fourstringburn]

Forum member @Slowmover will probably chime in on this thread.

He's knowledgeable on Cascadias and Kenworths installs.

On Volvos and probably some other trucks, it's worth the effort bypassing factory coax because the coax comes out of a multiplex box so the antennas are shared with CB, am/fm, and possibly TV.

 

[David 379]

Thanks for all the feed back on the Volvo, however I'm more interested in getting the the Pete perfect since that's now my daily rig , the Volvo is a VHD , and yes I was using the factory mirror perch mount with a grounding strap. The 655 will stay with that truck for whoever drives it after me so in other words their problem now lol .

I've attached a photo of my antennas , has anyone ever used these before as a single or cophased ?