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w6pea
04-07-2008, 11:59 PM
Okay
Here goes I want to get an amp to run behind my IC-706-MKIIG, I am using a Side kick antenna. Works good but people say I have a low signal. :eek:

I was thinking about getting an Mobile Amp but don't know which one to use.
Thanks
Pat w6pea

Richard Stouffer
04-08-2008, 06:28 AM
A friend with a 706 MII has been experimenting with two difference tuners for mobile operation into to a Hi-Q antenna. He tried the Ameritron 500, buy it doesn't fine tune well. He switched to the LDG 1000PRO and seems to have pretty good luck with it. If you're not famaliar with it, the Hi-Q has a remotely tunable coil.

w6pea
04-08-2008, 02:07 PM
Thanks Rich.

I had experience with Hi-Q Antenna's. They are pieces of JUNK as far as I am concerned. I wouldn't wish one of them on Osama Bin Laudin :eek:

I have the High Sierra sidekick. And am very pleased with it.
73 w6pea

P.S. When I bought my Hi-Q I was only a Tech. I complained to Charlie about the antenna and the install he did. He said because I was only a Tech I did not deserve to own one of his creations as he put it. bottom line I gave it the old heave ho. I gave it to a friend and he could never get it to work either. and he was an Extra at the time he's now SK N6ALA was his call.

w7wv
04-08-2008, 02:42 PM
I ran HF mobile for a time with IC-706 series radios and High Sierra screwdrivers. I never had a problem but we were not at the bottom of the solar cycle at the time either.
I had both the 1500 and 1800 series of antennas and have not personally used the SideKick.
Are you running this rig in an RV? If so I would think DC power requirements are going to be a concern. Even a smaller amp will draw lots of DC power as you most likely know. I would not personally want to put that kid of a draw on my RV batteries.
Most people I know who ran amps HF used the solid state amps. And many of those kept the transmissions short or ran additional means of supplying current to the amps.
This is from the manual on the Ameritron ALS-500~~

The ALS-500M uses two pairs of 2SC2879 transistors operating at 13.8 volts nominal in a push-pull output configuration.
High quality RF components combine with load fault sensing, temperature protection, and one switch frequency selection to
make this one of the simplest and easiest to operate amplifiers today. The ALS-500M operates on 13.8 Vdc electrical systems
and draws a peak current of 80 amperes at full output.

That kind of current draw is very hard on batteries in an RV if that's the way you are set up. For the amount of signal level you will gain with 500 watts I am not sure it's worth all the trouble.

I have run a number of amps at home but having 120v or 220v available makes a big difference. And at the price of gas today I would not want to think about running a genset for a couple of "S" units.

Not trying to tell you what to do, but to me for the overall expense and what you will get out of it the whole thing mobile is just not worth it to me.

Now as to your low signal the other parties are reporting. I assume your mic gain is set and you are observing your ALC? I always pushed the ALC on the meter on ICOMs I had in the past pretty hard without a reported problem.

I assume your tuning indication is good after tuning the screwdriver to your desired freq?
Is your antenna mounted up so that the element is not along side the coach (again assuming RV here). I have run into a number of RVers that mount screwdrivers and other antennas on the side of their coaches and then find the performance is not what they expected.
I have been told "but the coach is fiberglass" only to find and show the owner that the coach has metal framing like mine does under that fiberglass causing problems for the antenna.
And is your antenna ground properly bonded to the ground on your RV? I know High Sierra recommends their braid but I have used plain old plumber's tape as a great substitute. You know, the stuff they used to hang pipes with? If you look you can even find it in hardware stores copper plated steel which I prefer. I learned that trick from a 52 year ham friend that is now an SK.
Not an expert here, but I did work an antenna shop and on radio gear for the Navy as a civilian and been playing with this stuff for awhile.
Just trying to give you some ideas for improving your signal.
Semper Fi in your sig? I was Army 66-72. Radio operator and instructor.

Manual Garcia O'Kely
04-09-2008, 01:40 PM
Yep, you have the ALS-500 the SGC Smart Cube and the Tokyo Hi-Power 400 watt offering.

Most guys who mobile with amps use a rather large battery AT the amplifer, in addition to heavy gauge cables from the primary auto battery - This allows the battery to compensate somewhat for the voltage drop.

From what I've read, the SGC is pretty robust and will take lower voltages fairly well, but most of them will draw a max of 80 amps or so - SGC says 40 average on SSB.

Your main concern when running on storage batteries alone is the voltage drop - it's going to take a fair sized battery bank to give you an average of 40 amps for very long.

I don't have any good advice but it would not surprise me if 200+ amp/hour capacity is needed to give a couple of hours of amp operation - although when receiving obviously the draw is much less.

So then the operative question is 'how big IS your house battery?'

Richard Stouffer
04-09-2008, 09:01 PM
I have a Power Cube and it is robust. I've tried with limited success to use it as a base station unit, but the power supply requirements can be an issue. I have been using a 50 amp continuous, 70 amp unit peak with limited success, but a 90 amp peak is recommended. I will eventually try to rig it for my mobile operation and that, in my estimation, is going to require another battery, and the closer that battery is to the amp, the better.

Here's a link that does a very good job of detailing mobile installations for the Power Cube:


http://www.sgcworld.com/Publications/Books/GoMobilebook.pdf

By the way, the Power Cube is a lot of bucks for 500 watts, but it is built like a tank.

Richard Stouffer
04-09-2008, 09:06 PM
I forgot to mention, the pdf link I provided does a very thorough of explaning mobile power requirements and the sizes of batteries and alternator that you can get by with.

w7wv
04-11-2008, 05:14 PM
I think he either chickened out or is trying to figure out just how long he can key down with 2 house batteries! :radio:

w6pea
04-12-2008, 02:19 AM
No :bleh:
I have 8 house battery's. And 2 chassis battery's and 2 alternators, just like in an ambulance.

I had 2 coach batterys and added 6 more.:radio:

w6pea
04-12-2008, 02:22 AM
Also a good mobile amp is a little more :money: than I want to spend. Any way I don't spend a lot of time on HF any way. I need to do a little more experimenting

w7wv
04-12-2008, 08:23 AM
Yes cost for the gain is expensive.
You will find that improving your antenna may just give you what you want assuming you have a problem at all.

w6pea
04-13-2008, 12:11 AM
I don't have too much of a problem. Yes I do use it on a tripod. I took it over to the RV today. Where we store the RV is close to the bay. I worked Seattle, Portland, on 40, 20, 10, I worked a station in Montana, and one in Utah, and another in Iowa, on 75/80. Without an amp. So part of it is conditions and location, and how you are set up.

73 W6PEA

w7wv
04-13-2008, 10:49 AM
Interesting, are you using a radial system when using the tripod?
Your screwdriver uses your framing and such on the RV for radials.
You may find this post interesting~

http://forums.qrz.com/showthread.php?t=93082

I know for a time when I had problems with my property and antenna restrictions I ran my HS-1500 on the roof with 8 each 10' radials which was what was recommended by High Sierra.
I was not impressed with it's overall performance but that's all I could get away with at the time.
That same antenna, mounted on my truck properly, with the same radio (IC-706) was outstanding.

w6pea
04-14-2008, 01:57 AM
When I am using the tripod, I am using 8 radials. I ordered a set like comes with the tripod but at 25 ft. length. At home I use the radials that came with the tripod. Because I mount the antenna and tripod on my wooden balcony. I live in a condo and I have to deal with the HOA-Nazi's.

The best part was when they told me I had to take down my antenna, and their own lawyer told them that as long as I was a licensed Amateur and they allow satellite dishes to be mount on poles on the balcony's they would loose in court if I sued them for not letting me put up an antenna. So I have a antenna on a 12ft. pole and I also put up my tripod. Their lawyer also said I was with in their set height for satellite dishes, and as long as I didn't go any higher they couldn't do anything. But this guy is a real clown, he said that according to the FCC I could put up an antenna up to 200 ft. without a special permit. But he didn't read farther into the FCC Reg. book that says if we signed a cc&r we had to abide by the HOA Rules.:jitter:
God bless cheap HOA'S and lawyer's that hire idiot para legals.

73' de w6pea

w7wv
04-14-2008, 09:16 AM
You are lucky. When I first retired and got my license back I was on rental property with my home.
I put up an inverted "V" on the roof, after reading my property lease carefully and finding nothing.
(This was a manufactured home that I had on leased property)
The landlord of the property gave me a lot of trouble and tried to say I could not have that up there.
I countered, put a TV antenna on top of the inverted V mast and told her she could not make me take that down. And after all the antenna was on my roof and not on her property, as such.
Of course she never knew that the "guy" wires on two sides were still my inverted V.
She contacted her attorney and he told her to give it up.
Note, this lady was raised in East Germany under communist rule and I guess she thought she she treat people that way she was raised.
I lived on the property for just over two years. She was nothing but trouble and very bitter about everything.
Currently where I am located on acreage I have no antenna restrictions. No permit is required for a tower here yet either. But we are going full time and selling the property so I will lose that advantage very soon.

w6pea
04-15-2008, 01:37 AM
If my wife doesn't get a new contract with the school district we will be going full time in sept. :eek::radio: