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HF in the mobile ??? or just 10 meters???

Captain Kilowatt said:
Tuning was not the issue for me but signal strength was. I used copper strap as well, about 8 inches of it, from tuner to feedpoint. If you had good signals on both RX and TX then you are in the minority as almost anyone that has used such a setup reports crappy performance on 80m and barely marginal on 40m.My 80m Hamstick worked better and actually allowed me to work Europe from the mobile on 80m on many occasions where the 102 and tuner sucked.
Click to expand...
On reflection, I must now agree with you. I DID NOT in fact use a 9 foot whip, but it was a 8 foot long, 80M hamstick. Others who have tried the 9' whip/antenna tuner have also reported extremely poor performance on 80M. I will assume that the tuner, provides the requisite match to the whip, but the short length of the whip is too inefficient to to be useful. A proper, 8 foot 80M Hamstick ran circles around the tuner-fed 9 foot whip. Obviously the efficiency is far superior to the 9 foot whip, though bandwidth is next to nothing!

Now I wonder... how would an 80M Hamstick perform on 10M? Would the high VSWR at the antenna feed point (notwithstanding the tuner) compromise performance?
 
At least the seller is truthful about his coil.
As soon as I saw the picture, the first thing that popped in my head was "inefficient", then while reading his description he says it isn't as efficient as larger coils, which is very true.
Then he goes on to say that it has "good gain" which is laymans terms for it's not entirely a dummy load, it does resonate.

That's the biggest drawback to mobile HF, you ARE going to be at a disadvantage no matter what you do, you just have to decide how much of a disadvantage that you want to have.

Large coils that clear the roofline are the most efficient, coupled with the longest whip that you can get away will work very well... as long as you take care of a few other details like bonding and not shorting out too much of the coil when you try to tune a lower band (higher freq).

I'm old school and would rather have a tuned antenna than a whip attached to a tuner.
Hamsticks and screwdrivers aren't for me, it's either Bugcatcher style or Hi-Q.
 
That coil is designed as an "Outbacker" type antenna loading coil. On the lower HF bands it will perform as badly as the antenna it's a copy of.
There are so many 'mis-truths' in that advertisement it's amazing. Taken individually, everything said is in fact true. BUT, as it's presented about this coil, it's either misapplied or out right 'poo-poo' since it doesn't apply at all.
Coils provide no 'gain' at all, that's just silly. They supply inductance and inductive reactance and that's all they can do. How that inductance is applied can certainly affect the performance of the circuit it's used in, and that circuit may 'amplify' something, but the coil it's self is only a part of that, certainly isn't the direct cause of it.
If you weighed that eBay coil, computed what it would be worth if it was copper and gave that price for it, you'd still have been taken to the cleaners.
- 'Doc

(Just for grins, did you know that Henry Allen used to make two versions of screwdriver antennas? One was low, the other high power.)
 
Captain Kilowatt said:
Forget about using a 102 whip and a tuner below 20m. Been there done that. 40m sucked big time and 80m was just not there at all. It did work quite well above 20m however.
Click to expand...

Agreed, I've tried everything over the last 25 years mobile and bands lower than 20m mobile are just dissapointing. You need big antennas that a vehicle just can't accomodate and shortened antennas close to the ground on low bands just can't work well. Now I stick to 10m and was thinking about getting the 20m MFj SSB rig again. I ran one for two years mobile with a Hustler mast and resonator and it worked pretty well.
 
I used to take the mobile to work before I retired. Spent a lot of time playing radio in various ways, mostly on the lower HF bands, 80 meters in particular. I used a 'Texas Bugcatcher', but usually moved the radio inside the building running a coax extension to the car. I did quite well doing things that way. A lot of it had to do with where I was parked. Move ten feet in any direction and things really changed. Lots of metal in the ground for various reasons and it stayed wet a lot. Things would have been easier/better if I could have put up a usable antenna at the work site, but that wasn't possible. Did several WAS's from there, and several other things that were an accomplishment as far as I was concerned. Best way in the world? Of course not, but it wasn't as bad as it could have been either. Probably did as much at work as I ever did at home where I did have 'better' antennas.
Tried 160 meters once or twice. That was probably the worst example of futility as I've ever experienced! :) Couldn't get 10 miles. Heard some people, but never could talk to them. Oh well...
Mobile antennas do work even if they aren't very efficient at all. Sometimes it just doesn't take much efficiency' to do what you want to do. And if it ain't big and ugly it ain't 'purty' anyway...
- 'Doc
 
Personally, I'm still on the fence about full HF in the mobile. Right now I'm 10/11 metres with a whip and my Optima. With winter coming on soon, I'll be watching the few locals as what they do. Most of them run ham sticks or Hustlers. It is very good reading BTW.
 
My last run with full HF in the vehicle was with a Hamstick for 80m and 20m and a home made loaded whip for 15m. With those three bands something was open to somewhere at any time of the day or night. Not so sure what I am going to do with the new truck however. My work is four minutes from home so I do not spend much time at all in the mobile. I may go ahead and outfit it with the ability to just slip the FT-857 in if/when the mood hits me however.I can see a 2m rig going in however either with or without the FT-857.Presently looking at making a bracket to mount antennas on the rear of the box using the tailgate latch bolts and avoiding any holes in the sheet metal.
 
Captain Kilowatt said:
Presently looking at making a bracket to mount antennas on the rear of the box using the tailgate latch bolts and avoiding any holes in the sheet metal.
Click to expand...

I'll have to search on another forum, but there is someone who makes several different styles of brackets that do just what you want.
The few people that use them, brag about them. And they even make a style that bolts in place using the factory tail light screws.

Off to search through a couple of years worth of posts lol:headbang

[Edit] well I looked through hamsexy and didn't see the post I remember, could have sworn it was there. Might be over on batlabs...

Anyway, a guy here in the US makes these mounts, they are kind of similar to the Firestick SS-204A mount.
It's a plate that you mount vertically between the tailgate and tail light and it's bent around horizontally so it barely covers any tail light at all.
Maybe you can get a mental image of that.. here's a pic of the SS-204A just to give you an idea. It's not a bad mount, just bent around too far for tail light placement.
GD4sV.png
 
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Captain Kilowatt said:
My last run with full HF in the vehicle was with a Hamstick for 80m and 20m and a home made loaded whip for 15m. With those three bands something was open to somewhere at any time of the day or night. Not so sure what I am going to do with the new truck however. My work is four minutes from home so I do not spend much time at all in the mobile. I may go ahead and outfit it with the ability to just slip the FT-857 in if/when the mood hits me however.I can see a 2m rig going in however either with or without the FT-857.Presently looking at making a bracket to mount antennas on the rear of the box using the tailgate latch bolts and avoiding any holes in the sheet metal.
Click to expand...

I was thinking of using my backrack if i try one of the screwdrivers. The housing would be behind the cab but any "stinger" would be above the truck's roofline.
 
QROdx said:
I'll have to search on another forum, but there is someone who makes several different styles of brackets that do just what you want.
The few people that use them, brag about them. And they even make a style that bolts in place using the factory tail light screws.

Off to search through a couple of years worth of posts lol:headbang

[Edit] well I looked through hamsexy and didn't see the post I remember, could have sworn it was there. Might be over on batlabs...

Anyway, a guy here in the US makes these mounts, they are kind of similar to the Firestick SS-204A mount.
It's a plate that you mount vertically between the tailgate and tail light and it's bent around horizontally so it barely covers any tail light at all.
Maybe you can get a mental image of that.. here's a pic of the SS-204A just to give you an idea. It's not a bad mount, just bent around too far for tail light placement.
GD4sV.png
Click to expand...


I think I know the place you are referring too but it escapes me at the moment as well. It will come to me. I am pretty handy with making mounts etc and have access to some nice aluminum and stainless steel plate up to 1/2 inch thick thru work with most of it either 1/4 or 1/8 inch which would be perfect in stainless. I just needed an idea of WHERE to mount it. I can come up with the HOW part after I figure out the where. It now looks like that part is taken care of as well. :thumbup1:
 

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