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w5sq
09-25-2014, 11:51 AM
Hello,

Does anybody have experience using an ALS-500 or any mobile HF amp in an RV? I have used my ALS-500 for yrs in my old 93 Dodge diesel pickup which does not have a computer operated engine. I now want to operate from my 2006 Air Stream Sprinter RV and do not want any problems from stray RF getting into the Sprinter diesel electronics. Any comments?
Joe
W5SQ

wa8yxm
09-25-2014, 12:51 PM
While I can not speak for Motor homes. I know car makers are now testing with high power radios.. In many cases they give a Ham Radio Operator Engineer a test car to drive, complete with a full gallon of radio..... The reason.. Well.. Imagine the following scenario.

Patrol officer is doing Speedlimit plus when IDIOT flys by so fast he does not even know he passed a patrol car.. Officer puts the pedal to the metal to catch this idiot before he kills someone ... Dispatch this is Adam Twelve (Ok so I picked a TV show for the car ID) I;M iIN (Sputter sputter cough engine dies), I was in pursuit of a speeder but my car died.

I actually know a trooper that sort of happened to.. Only .. Well major differences.
(1: He was trying to join in a chase)
(2: He put the pedal to the metal, then dropped it in Drive, and blew every seal in the tranny,, Engine kept running)

(We told him DRIVE FIRST, then floor it)

w5sq
09-25-2014, 02:59 PM
Glad to hear the manufacturers are doing research. I had it in my 98 E300D and had a slight mis match at one time and got a bunch of garble de gook across the dashboard. Turned the car off and waited awhile and recycled the ignition a couple times and everything went back to normal. Was worried sick I was gonna have to take it into the Benz dealer and open up my wallet for re-programming or new computer or whatever....

Joe

N3LYT
09-25-2014, 07:07 PM
Most manufactures set the limit at 100 watts for mobile operation. Yes I know those that use 500 but they are lucky. My old Audi's cruse control would drop out as soon as I transmitted on 6 meters at a 100 watts.The newer the vehicle the worse it gets every thing has to be hardened for RF just so many things the public demands in their living room on wheels.

Mr. Ham
09-25-2014, 10:33 PM
Radio 101

Amplifiers are only used when all other attempts at using a more efficient antenna has failed.
Amplifiers do not amplify the receive, only the transmit.
Even if you amplify the receive - there is so much noise, there is no benefit.

Where I come from, people uses amplifiers to make their signal appear louder.

This limits you to talking to other people that has made their signal louder, or someone that just happens to be in your range - that can hear you, that you can hear.

Keep both hands on the wheel and quit trying to be a CB'r.

The State Police here has a Falcon radar gun that is equipped with a vehicle shut down mode that selectively shuts down the electronics of the vehicle they are in pursuit of.
Unfortunately, if they press the trigger, there is no way to keep the RF from shutting down their own vehicle.

In todays world if you want to disable a persons vehicle, you run the VIN, call Onstar and let them shut it off for you.
This is the reason why I do not like new vehicles with factory equipped OnStar. Even if you have not paid the bill, it still is hard at work gathering information and selling it to those that are willing to pay for it.

Where you go, how frequent you go there. How fast you go, how many revolutions per a minute your engine turns etc..
If your vehicle is stolen, they can usually find it, or give you the last known location within about 3 minutes of when you call them.

Many new Ipods, Ipads, etc also have the same capability.

Mr. Ham
09-25-2014, 10:37 PM
If I had a all metallic vehicle and I wanted to operate HF, the very first thing I would do is call DX Engineering and buy about 100' of 3 inch copper strap and bond all the surfaces together to make the vehicle appear to the RF as being one solid object.

Unfortunately in today's world, everyone wants to be a CB'r and just stick a mag mount antenna on the roof and transmit.
The art of installing radios has been lost somewhere in the transition between the older generation and the newer.
40 years ago, vehicles were mostly steel, with very little plastic, today vehicles are plastic and exotic materials, and yet we still want our radios to work the same way.

There is very little that we can do about it except try to use Hamsticks or Tarheel antenna's and a antenna tuner...

If you are going to run 1KW on 40 or 80 meters and you do not have sufficient surface area, you are going to need one heck of a antenna tuner.

N3LYT
09-26-2014, 11:28 AM
Not a lot of chance in a pile up no problem hearing a big station with a big beam but a lot of problem hearing my little pw station on a 100 watts and a dipole with 15 others calling some times an amp is the only way to get a rare one. The Falcon radar units will not stop a car they are designed to defeat radar detectors they lock speed and stop transmitting. Data from a on board engine computer is read only there is no external input. On Star and your cell phone do have GPS TX data you can turn that off on the phone to 911 only that's up to you.

N3LYT
09-26-2014, 11:44 AM
You can weld the doors shut and bond the exhaust to the radio use a 100' of copper and you will still have all most worthless ground plane. Vehicles make very bad ground planes for HF. The bed of my pick is composite my HF still works. The key is a resonate antenna and not worrying about the fact you are working QRP with a 100 watts.

W5DOK
09-26-2014, 05:10 PM
Although cars were all steel 40 years ago, radios were also not nearly as sophisticated as todays radios. My motor coach is mostly fiberglass, yet my Tarheel 200 works great behind my Icom. The antenna is only bonded to the coach frame for a ground plane. Although the radio has a built in tuner, it's rarely used. I select a band and the radio tunes the antenna to that band.
I've never owned a cb radio, so I don't consider myself a cb'er. BTW the motor home is an electronic marvel and the Ham equipment has never given it any issues.
Doc

w5sq
09-26-2014, 10:13 PM
I have operated an ALS-500 amp generally running about 400 watts for close to 20 years in an older 93 Dodge Cummins Diesel pickup with a triple mag mount on top of the cab and mfj hamsticks. The amp makes a big difference in maintaining regular contact with a group of guys I talk with frequently. A lot of the time they would hardly hear me with 100 watts, particularly on 75M, since the ant is so inefficient. I will get it worked out sooner or later, but just thought I would ask on here just in case someone had been there done that. CB radio would be new to me; I have been a ham since 1960, right after they took the 11 meter band from us. Thanks for all the feed back.

N3LYT
09-27-2014, 09:07 AM
I have operated an ALS-500 amp generally running about 400 watts for close to 20 years in an older 93 Dodge Cummins Diesel pickup with a triple mag mount on top of the cab and mfj hamsticks. The amp makes a big difference in maintaining regular contact with a group of guys I talk with frequently. A lot of the time they would hardly hear me with 100 watts, particularly on 75M, since the ant is so inefficient. I will get it worked out sooner or later, but just thought I would ask on here just in case someone had been there done that. CB radio would be new to me; I have been a ham since 1960, right after they took the 11 meter band from us. Thanks for all the feed back.

Yeah you are at a big disadvantage mobile the guys at home have workable setup. A 128' simple dipole in the trees at the house as opposed to a stick on the roof is just is not fair. I have never stopped to figure out the ERP of a mobile antenna but I'it can't be no more than a hand full watts mobile. I never had much luck with the sticks the only ones that worked OK for me were 10 meters. I use a LiLTarheel with a long whip back by the tail gate on my pickup.

wa8yxm
09-27-2014, 10:01 AM
Several comments:
First: Though Radios were not as sofisicated 50 years ago 1,000 watts is still 1,000 watts.
But cars, 50 years ago, had simple mechanical analog computers, not todays modern digital electronic jobs and the mechanical computers of 50 years ago (Spark advance system, carb, ect) were impervious to RFI since they were not electronic, They could, however, cause RFI. (interference to the radio).

Though 100' of heavy duty grounding strap sounds good, There are two schools of thought.

ON Ham Nation: Bob Heil likes single point grounding , he uses outlet adapters to "Lift" the ground pin on his transmitters so the only ground is via the coax to the tower ground.

George Thomas uses a big heavy ground bus and multiple Straps a-la DX Enginering.

As to who is right and who is wrong..... The answer is actually both, under different conditions. I have to admit there are times when I wonder why the 3rd pin on the outlet.. IE: Laptop computers with all plastic housed bricks and so on, There is no direct connecting between what I'm touching and anything outside of the box.

W5DOK
09-27-2014, 05:20 PM
True. 1000 watts is still 1000 watts. I have a AL-1500 sitting 2 feet from this computer and 15 feet from a large TV. There is never a ripple on the TV or any trash on my computer. My old Henry from 40 years ago would take a TV a block away off the air and talk on the church organ 2 blocks away. RFI suppression in todays electronics is superb and unwanted harmonics are almost a thing of the past. My RV is practically all processor controlled. Lights, climate control, entertainment, navigation, leveling, ant the engine and transmission. Yet I have never have had any issues with interference from my ham equipment and I routinely run 500 watts on SSB. (I know. The Tarheel is rated for 200) My only attempt at RFI control is that the antenna is mounted on the rear ladder and the ladder has a ground strap going to the frame and I have the radio and amp grounded directly to the frame. I always check with my neighbors to make sure that I'm not bothering their electronics and so far, nary a complaint. Most of the hams that I have ran across in rv parks traveling around the country, are very careful not to interfere with their neighbors and as a result, most rv park owners are very tolerant of our antennas, up to a point. They get a little testy about long wires running thru the trees, but usually allow moderate sized ground planes and beams.

N3LYT
09-27-2014, 08:01 PM
Several comments:
First: Though Radios were not as sofisicated 50 years ago 1,000 watts is still 1,000 watts.
But cars, 50 years ago, had simple mechanical analog computers, not todays modern digital electronic jobs and the mechanical computers of 50 years ago (Spark advance system, carb, ect) were impervious to RFI since they were not electronic, They could, however, cause RFI. (interference to the radio).

Though 100' of heavy duty grounding strap sounds good, There are two schools of thought.

ON Ham Nation: Bob Heil likes single point grounding , he uses outlet adapters to "Lift" the ground pin on his transmitters so the only ground is via the coax to the tower ground.

George Thomas uses a big heavy ground bus and multiple Straps a-la DX Enginering.

As to who is right and who is wrong..... The answer is actually both, under different conditions. I have to admit there are times when I wonder why the 3rd pin on the outlet.. IE: Laptop computers with all plastic housed bricks and so on, There is no direct connecting between what I'm touching and anything outside of the box.

With the ground pin it's all about line noise and the computer if there is a sub panel involved it has a floating neutral so a ground pin is needed. Me I believe in single point grounds for my home ham gear and tower every thing is linked together including the house power.

Mr. Ham
09-28-2014, 01:23 PM
Not a lot of chance in a pile up no problem hearing a big station with a big beam but a lot of problem hearing my little pw station on a 100 watts and a dipole with 15 others calling some times an amp is the only way to get a rare one. The Falcon radar units will not stop a car they are designed to defeat radar detectors they lock speed and stop transmitting. Data from a on board engine computer is read only there is no external input. On Star and your cell phone do have GPS TX data you can turn that off on the phone to 911 only that's up to you.

http://www.policemag.com/channel/technology/articles/2007/11/cutting-out-the-chase.aspx

wa8yxm
09-28-2014, 03:14 PM
With the ground pin it's all about line noise and the computer if there is a sub panel involved it has a floating neutral so a ground pin is needed. Me I believe in single point grounds for my home ham gear and tower every thing is linked together including the house power.

Perhaps I was not clear enough on the grounding /ground pin.

I only presented two viewpoints, I am not supporting either one. Only presenting, I sit firmly atop the fence on this one.

As for the floating neutral in the sub panel..... NO, it does not float, it is bonded to ground... You just can not see the bond looking, as you are, at the sub panel.

Why is this,, Think about what "SUB" means, (it means it is off the MAIN panel and that is where they did the bonding of course)

However..... IT MIGHT FLOAT (in an RV) if you are running off the generator or inverter.

N3LYT
09-28-2014, 07:37 PM
Perhaps I was not clear enough on the grounding /ground pin.

I only presented two viewpoints, I am not supporting either one. Only presenting, I sit firmly atop the fence on this one.

As for the floating neutral in the sub panel..... NO, it does not float, it is bonded to ground... You just can not see the bond looking, as you are, at the sub panel.

Why is this,, Think about what "SUB" means, (it means it is off the MAIN panel and that is where they did the bonding of course)

However..... IT MIGHT FLOAT (in an RV) if you are running off the generator or inverter.

In a sub panel (rv's) or any panel behind a main breaker the neutral is not bonded to the ground. The lugs are not bonded to the panel the ground is. Sub panels require a ground, a neutral and a hot one good reason for this is camp ground wiring if the hot and neutral are reversed you could end up with a hot frame not a good thing chances are it would trip the breaker but suppose the ground is not good? At the main panel yes indeed the two are bonded together but that all changes with a sub panel this is why main panels have 4 lugs two hot one ground and one neutral if it is a main there is a bonding screw that is installed to bond the neutral to the ground in a sub panel the neutral is insolated from the ground.

N3LYT
09-28-2014, 07:47 PM
http://www.policemag.com/channel/technology/articles/2007/11/cutting-out-the-chase.aspx

I have used Falcon radar's they will not stop any car. In the future maybe but not likely it would require too much power.

NN5I
09-28-2014, 08:18 PM
The State Police here has a Falcon radar gun that is equipped with a vehicle shut down mode that selectively shuts down the electronics of the vehicle they are in pursuit of.
Unfortunately, if they press the trigger, there is no way to keep the RF from shutting down their own vehicle.

I have used Falcon radar's they will not stop any car. In the future maybe but not likely it would require too much power.

Oh, c'mon, don't bother him with reality. The poor fish may actually believe that nonsense about shutting down a car.

Mr. Ham
09-28-2014, 10:04 PM
Well Carl, I guess in your own little world, your rose colored glasses are on pretty tight.
In fact the PA State Police has already experimented with this technology.
The legality is that if it causes someone to wreck, they are liable, especially if they cannot control it and it causes someones car to wreck that has not committed a crime.
It is much easier to just call On Star and have them disable the engine.

NN5I
09-28-2014, 10:20 PM
Until you cite an authoritative report that can be verified, I will assume that some cop (or other person) told you that and is still snickering at your credulity.

Oh, by the way, how about telling us your name and callsign?

N3LYT
09-29-2014, 08:20 AM
Retired Cumberland County Maine Sheriff office electronics dept head. Prier to joining the PD I taught automotive electronics for Bosch. So I do have a pretty good ideal how it all works. OnStar is capable of shutting down a car it is a system designed by GM and is part of the overall electronic system it is not a retro fit. It's not for nothing GM owns Hughes in 1985 Hughes merged with Delco yep the people that made the cars electronics. GM is the only place you will find that feature.

NN5I
09-30-2014, 10:56 AM
Retired Cumberland County Maine Sheriff office electronics dept head. Prier to joining the PD I taught automotive electronics for Bosch. So I do have a pretty good ideal how it all works. OnStar is capable of shutting down a car it is a system designed by GM and is part of the overall electronic system it is not a retro fit. It's not for nothing GM owns Hughes in 1985 Hughes merged with Delco yep the people that made the cars electronics. GM is the only place you will find that feature.

That's credible. The other part of Mr Ham's claim -- wonder what his real name and callsign are -- about shutting a car down by a blast from a portable radar, even if vehicle-mounted and not handheld, is not. Some warship radars might do it to a modern vehicle, but you can't mount them in a cop car.

But you (N3LYT) really know more about that than I do. If you say I'm wrong I'll believe it.

N3LYT
09-30-2014, 01:13 PM
That's credible. The other part of Mr Ham's claim -- wonder what his real name and callsign are -- about shutting a car down by a blast from a portable radar, even if vehicle-mounted and not handheld, is not. Some warship radars might do it to a modern vehicle, but you can't mount them in a cop car.

But you (N3LYT) really know more about that than I do. If you say I'm wrong I'll believe it.

I can tell you a war ships radar will take the front end out of a police radar unit.

W7JZE
10-01-2014, 12:18 AM
I can tell you a war ships radar will take the front end out of a police radar unit.

As well as your ability to procreate :oops: .

Radio
10-01-2014, 05:37 PM
As well as your ability to procreate :oops: .

And you ability to see :cool:

A friend of mine was an AWACS operator back when you had the revolving saucer on the B707. The local constable liked to ticket airmen coming into town with his radar and the fines were quite hefty.

You're not supposed to run the big radar on the ground but when they would see him parked beyond the fence they gave him a blast. Put the hand held radar in the shop for 3 weeks at a time.

:cop:

N3LYT
10-01-2014, 07:59 PM
I did not say how I knew it would!

NN5I
10-01-2014, 10:27 PM
Now that's funny.