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Finally bought a Sirio 5000 to try...
- Thread starter The Jerk
- Start date
Well, might as well get my .02$ in too. Took some advice (thanksguys) and got the performer 5000, using a mag mount for now, but will be going to hardmount. No shipping issues, assembled easy, came in a long, triangle tube. Dont have analyzer just swr meter.........out of the box- 1.05:1 on ch1, 1.15:1 on ch40; left it alone. First immediate note was rx WAY improved. Right now running stock Cobra 25 ltd classic, talking about 10 miles before I start to run out........hey, its New England, lotsa hills, valleys, and so on. One issue.....put a small amount of anti-seize on the threads; thru the winter with salt spray and such found the handle starting to seize up. Since i park in a garage every night it gets used a lot, and after I cleaned the threads and antiseized them have not had a problem. Note that the bolt and the base halves are different materials, so this will cause it too. No issues with water intrusion, and have had numerous good get-backs from drivers on my commute. Found that under bad weather up here, pulls in skip from Tx, Ga, Fl that I never heard on my K40; am still working on setting up my 148gtl in the car so i can get out on ssb. Oh, one last thing, the swivel is a tapered fit, don't overtighten the handle, and when you loosen it to drop stinger gently rock antenna 90 degrees to swivel plane andit will loosen up easy. Good advice from the guys in the forum......y'all know who you are!!!!!
When you do eventually hard mount it Redbeast you may find you need to trim the whip especially if you follow the advice about bonding at www.k0bg.com as you'll find it ends up being resonant below 26MHz. You may find though that although the SWR is higher than you'd ideally like that it's low enough on the channels you use.
Ok, i definitely get the bonding idea, but let me ask you this. The car in question is a geo metro......first, its a real small car, second, its unibody...meaning most of it is already bonded, the only metal body parts not welded together are the front fenders. So, will bonding be a real issue here? Seems to me im only going to get just so much with so little sheet metal, and isnt that why we use base load antennas-esp with late model plastic and fiberglass? I know an antenna tuner should be my next thing, but as always "family first" . BTW, finally had a long convo with three other drivers last night on the road, excellent reports from all three on my getout, and thats on a stock cobra 25 ltd.....still havent rigged for my 148gtl. I think most of you would go along with me .......if it aint broke, fix it til it is!!!!!!!!LMAO
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Yes bonding is an issue. I'm from the UK and pretty much 99% of cars sold here in the UK and the EU are a similar size to yours and also unibody constructed like yours. Here's what I use.
(Old picture, antennas have changed. VHF/UHF Dualbander in the middle of the roof is now replaced with Sirio Performer 5000, screwdriver antenna is gone.)
On a small vehicle maximising what RF ground your vehicle represents is even more important than on a large one. Horizontal metal is more important than the vertical metal when it comes to RF grounds on vehicles because we're trying to get RF flowing on a good conducting surface and not the lossy ground below the vehicle and you have two panels which aide that which aren't welded to the main body, the hood and the hatch or trunk lid. The hood alone is going to constitute somewhere between a third and a half of horizontal sheet steel on the entire vehicle which is used as a RF ground. Whilst there is DC continuity between those panels and the main body the continuity for RF is very poor. Bonding across the hinges of the hood and the trunk/hatch to the main body improves RF continuity considerably.
The test to prove if I'm right or wrong is very simple. Mount your antenna, with an antenna analyser measure the frequency that the antenna is resonant on, where X=0. Bond the hood to the main body as described on K0BG.com. Without altering the antenna at all check the resonant frequency again. I can guarantee 100% that it has changed and it will have dropped, probably a couple of hundred kHz. If you don't have an antenna analyser use a SWR meter and before you bond the hood measure the lower point where the SWR goes up to 2 and the highest point where the SWR increases to 2. Do the bonding, remeasure and you'll find its moved several channels. Even when I bonded my hatchback, which is plastic over a metal frame on the lower half of it, I saw a frequency shift.
No. You use base loaded antennas with those types of vehicles to reduce the stress on the bodywork. If you move the load up higher you increase the "twisting" pressure at the bottom of the antenna when pressure such as the wind as you drive is applied to the antenna. If you want an example get a long screwdriver or stick and several quarters. Tape the quarters together into one lump and tape that lump to one end of the stick/screwdriver. Gripping the end with the quarters on using your thumb and forefinger, hold the screwdriver horizontally. You'll find you need to use very little if any effort to keep it horizontal. Next hold the screwdriver horizontally but by the opposite end, again with your thumb and forefinger. You'll find it a lot harder to keep the screwdriver horizontal. What happens there is what is happening to your antenna.
The trouble is that it is broke, you just don't have the knowledge or the test gear to know that it is but I would expect that on your magmount set up that when you started running some real power, like 100W, that you got signs that it was such as the dash gauges doing wierd things when you key up or the engine cutting out or you feel a tingling sensation when you key up or your TX audio becomes distorted. Chances are you're already experiencing issues on RX due to common mode RFI because of poor RF grounding, you just don't recognise them. Increased noise is the main one. In a rural setting with the engine running as I drive down the road on an empty channel I get S0 on my S meter, do you? I can hear weak stations with S0 signal strength on the meter with the engine running, can you? Or do you find when your engine is running your S meter is S2,3 or higher?
Making contacts isn't an indication its working properly. Making DX contacts is even less so. You can make contacts on a dummy load but it makes a piss poor antenna.
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I use a sirio performer magmount ... it works great on multiple vehicles as it can be adjusted 180 degrees ... goes from a van to a outback to a pickup with no hastle .. talks great and receives great wherever... checked the swr out of the box and made no adjustments to date..xxx
Another old post. Yep, I know. But, I'm hooked.
Just wanted to say that next to my 102 SS Whip, my Sirio Performer is the bast antenna I own. Out of about 30 or so different ones hahaha
Just wanted to say that next to my 102 SS Whip, my Sirio Performer is the bast antenna I own. Out of about 30 or so different ones hahaha
Out of 30 or so is a great ranking, to me.