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mobile gmrs (vfo)


Goliath
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I'm fairly new, I'm looking for a nice mobile rig that does vfo, not a big fan of this computer programmed radio, I do operate a baofeng bf-f8, a Motorola m1225 .. Any help would be great

 

Thanks Aleck, WQXQ966

 

VFO is illegal for GMRS. No radio that has VFO capability is type accepted for GRMS. Too much potential for off frequency interference. Modern synthesized radios that are programmed via computer are far less susceptible to wandering off frequency especially with someone manually tuning in the field.

 

The amateur bands are specifically allowed VFO.

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I'm fairly new, I'm looking for a nice mobile rig that does vfo, not a big fan of this computer programmed radio, I do operate a baofeng bf-f8, a Motorola m1225 .. Any help would be great

 

Thanks Aleck, WQXQ966

Do you notice engine hum with the M1225? I have 3 of them that do that. I am starting to phase them out with the CDM series

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VFO is illegal for GMRS. No radio that has VFO capability is type accepted for GRMS. Too much potential for off frequency interference. Modern synthesized radios that are programmed via computer are far less susceptible to wandering off frequency especially with someone manually tuning in the field.

 

The amateur bands are specifically allowed VFO.

Thanks for the info, actually good to know so many fcc  laws, I am scheduled to take my test for technician next week, so that'll open up alot of options... 

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I run a pretty tight electrical ship, try grounding right to the negative on your battery,  Here is a slightly advanced work up and explanation http://www.hamradioschool.com/going-mobile-part-2-solving-rfi-problems/

 

Most commercial radio manufacturers recommend grounding to the frame near the battery. Now, with the advent of the super high tech computer systems running everything in our cars and trucks, installers are finding that grounding the radio to the battery negative terminal is causing all kinds of havoc with the vehicle power control systems. Latest and best recommendation now is to ground at the point on the frame where the battery's grounding strap connects. It eliminates potential ground loops and yet satisfies the most finicky computer system.

 

Any recommendations on this subject that are more than a couple of years old are pretty much based on non-computer controlled automotive systems. If doing an install on a new or very recent model year vehicle, the old thinking has to be set aside. I know hams have pushed grounding to the battery negative terminal for many, many years, but it's going to have to change or we'll all be dealing with a new set of problems.

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Most commercial radio manufacturers recommend grounding to the frame near the battery. Now, with the advent of the super high tech computer systems running everything in our cars and trucks, installers are finding that grounding the radio to the battery negative terminal is causing all kinds of havoc with the vehicle power control systems. Latest and best recommendation now is to ground at the point on the frame where the battery's grounding strap connects. It eliminates potential ground loops and yet satisfies the most finicky computer system.

 

Any recommendations on this subject that are more than a couple of years old are pretty much based on non-computer controlled automotive systems. If doing an install on a new or very recent model year vehicle, the old thinking has to be set aside. I know hams have pushed grounding to the battery negative terminal for many, many years, but it's going to have to change or we'll all be dealing with a new set of problems.

Motorola has been calling for chassis ground since they phased the Twin V out of service.

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Motorola has been calling for chassis ground since they phased the Twin V out of service.

 

Very true, but I think the gist of this side conversation is really the need to abandon old amateur radio thinking. The mantra of ham radio for the last umpty-up decades has been to ground to the negative battery terminal. With the advent of today's sophisticated. multi-function on-board computer control systems, grounding to the battery is now proven to cause real problems in the functionality of those computers. And, as you pointed out in another thread on another forum, fusing the ground lead is likely to wreak more havoc than provide protection should the fuse blow.

 

The frustration here is that we have the same discussion over and over, and always leading to the the same conclusion. Then someone who has not read any of the previous discussions pops up chanting the "ground to the negative battery terminal" mantra. Here we go again. (sigh!)

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I spent a few hours reading through the owner's manual for my (new to me) 1998 Toyota Camry, and it was restated in RED INK at least a dozen times in the 495 pages to not connect stuff directly to the battery. In fact they thoughtfully provided an "auxiliary power port" rated 120 watts @ 12vdc nominal.

 

Unfortunately, I have two mobile radios to install, each of which can potentially draw up to 15 amps, so I have no choice but to find a way to fish some heavier wire through the firewall from the battery + and the - side's chassis ground point. :(

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Very true, but I think the gist of this side conversation is really the need to abandon old amateur radio thinking. The mantra of ham radio for the last umpty-up decades has been to ground to the negative battery terminal. With the advent of today's sophisticated. multi-function on-board computer control systems, grounding to the battery is now proven to cause real problems in the functionality of those computers. And, as you pointed out in another thread on another forum, fusing the ground lead is likely to wreak more havoc than provide protection should the fuse blow.

 

The frustration here is that we have the same discussion over and over, and always leading to the the same conclusion. Then someone who has not read any of the previous discussions pops up chanting the "ground to the negative battery terminal" mantra. Here we go again. (sigh!)

Things that we might trying to get stickied at the top of said forums...

 

Sent from my SM-T350 using Tapatalk

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I'm fairly new, I'm looking for a nice mobile rig that does vfo, not a big fan of this computer programmed radio, I do operate a baofeng bf-f8, a Motorola m1225 .. Any help would be great

 

Thanks Aleck, WQXQ966

http://www.miklor.com will specifically answer your question without all the "side band". and computer programmed is not as bad as you might think. but i personally cant stand chirp!!

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Most commercial radio manufacturers recommend grounding to the frame near the battery. Now, with the advent of the super high tech computer systems running everything in our cars and trucks, installers are finding that grounding the radio to the battery negative terminal is causing all kinds of havoc with the vehicle power control systems. Latest and best recommendation now is to ground at the point on the frame where the battery's grounding strap connects. It eliminates potential ground loops and yet satisfies the most finicky computer system.

 

Any recommendations on this subject that are more than a couple of years old are pretty much based on non-computer controlled automotive systems. If doing an install on a new or very recent model year vehicle, the old thinking has to be set aside. I know hams have pushed grounding to the battery negative terminal for many, many years, but it's going to have to change or we'll all be dealing with a new set of problems.

 

We run PM400's in the vehicles, I ran positive to the battery and ran my ground to the frame near the battery. No engine noise at all. I do on occasion get some noise near an older car at a stoplight, but that is on a signal at S1 or so.

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