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 Springer SWR Problem 
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Post Springer SWR Problem
Afternoon,

Trying to use a springer on my van but the swr is only low on 10m,
I need a good SWR on 10m for when I go on VW meets so we can all keep in touch.
I have it on a new triple magmount, tried other cb antennas and still no joy, also tried other mounts :banghead:
The springer obviously needs to be longer to drop the frequency but why? It's not easy adding length to the whip :blink:

If I put a pice of wire from the bottom of the coil to the last turn of the coil then the swr drops, I expected it to increase as it would short the coil.

:cry:


Mon May 04, 2015 3:44 pm
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 Springer SWR Problem 
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Post Re: Springer SWR Problem
It's low on 10m ...Good and expected.

When you short the coil what freq are you trying to load it on?

D

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Mon May 04, 2015 5:33 pm
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 Springer SWR Problem 
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Post Re: Springer SWR Problem
Sorry mistake in above post, it's got a low swr on 28Mhz but need it to work on 27.831.25 for meets and convoys.
If I short the coil then it drops the swr to 1.1 around the cb channel needed but the bandwidth is narrow so making it unusable on most the bands it's supposed to be used for, no good if we need to change channel.


Mon May 04, 2015 5:47 pm
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 Springer SWR Problem 
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Post Re: Springer SWR Problem
Hmmm,

clearly its not working as advertised. I'd send it back or call the shop. A CB aerial that doesnt work on the CB band is rather pointless.

I dont wish to teach granny to suck eggs but what type of SWR bridge are you using? I just wonder how accurately its being measured.

Ive never used this tye of aerial (though I have often often considered buying a pair just because they look cool and remind me of my wasted youth watching Them Duke Boys! Oh how I always wanted a Toyota HiLux with a brace of whips on.

D


D

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Mon May 04, 2015 6:54 pm
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 Springer SWR Problem 
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Post Re: Springer SWR Problem
The springer is a loaded 1/4 wave, the inductive loading gives it a narrow bandwidth - 27.83125 is no too far from 28.000MHz, however not sure where on the 10M band you have it resonated?
If you lengthen the top whip of the springer then you will get it on 27.83125MHz, however you will lose the 10M band frequencies you want to keep it on, the way I see it for a quick fix - leave it as it is and buy a cheap Eurosonic CB type ATU/Matcher off EBay for a few quid and plug it in-line with the CB then you can present a low VSWR to the CB radio.


Mon May 04, 2015 7:23 pm
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 Springer SWR Problem 
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Post Re: Springer SWR Problem
Using the MFJ analyser, I may have been hoping for too much from the springer as I wanted to use it on cb and 10m through a small mobile set I have, a matcher could be an option and possibly the only option unless one of these base loaded cb type antennas are better?
Earlier I was told the springer SWR changes as you drive due to the coil bouncing, that making it not a good choice.
Looks cool on the van though :cool:


Mon May 04, 2015 8:27 pm
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 Springer SWR Problem 
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Post Re: Springer SWR Problem
If you want an antenna you can use on the UK CB frequencies and the 10m band you need to be looking at a Sirio Performer 5000 or a Turbo 5000 but you'll have to trim the whip a bit. They have 2MHz bandwidth below 2:1.

My Sirio Hypower 3000 will do UK FM and the bottom half of the 10m band up to around 28.700.

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Tue May 05, 2015 11:37 am
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