Fiberglass trunk? Thanks a lot Ford.

[SafetyLighting]

So I have a 2011 Lincoln MKX here for some lights, a siren and an Astro25 Radio. I start drilling the hole for the antenna on the trunk and fiberglass dust shoots out. Yeah, the entire trunk assembly is molded fiberglass. The hole is already started so I have no choice but to mount the antenna there. :hissyfit:Anyone know how bad the lack of a ground plane will hurt the 800 radios?

 

[SireLite]

You could fit a large rectangle sheet of steel on the inside of the trunk And then attach the antenna through it.

 

[mjw357]

Can you install an elevated feed antenna that requires no ground plane?

 

[SafetyLighting]

Well, I cant mount the NMO mount now anyways because the fiberglass is too thick. So I'm going to talk to the customer tomorrow. I don't think they need to transmit anyways, just recieve.

 

[SlickTop Solutions]

Well, I cant mount the NMO mount now anyways because the fiberglass is too thick. So I'm going to talk to the customer tomorrow. I don't think they need to transmit anyways, just recieve.

There are deep mount NMO mounts available for mounting in areas with greater than 1/8" of material to mount to.

 

[NPS Ranger]

Buy a ground plane kit made for boats, which is basically a sheet of adhesive foil to go on the underside of the trunk lid, it will provide a decent ground plane.

 

[Steve0625]

Another item which can be fabricated into an excellent ground plane in most any vehicle is window screening material, as long as it is made of an electrically conductive material like aluminum. I have even seen copper screen used for this purpose.

 

[C2Installs]

Anyone know if the new Ford NGPI police cars are going to have the same basic trunk lid?

 

[FireEMSPolice]

IIRC, the aero CV's had a fiberglass trunk-lid

 

[litsnsirn]

I think you might mean aluminum on the 96 & 97's.

 

[K9Vic]

IIRC, the aero CV's had a fiberglass trunk-lid

They have always been and are still aluminum from 92-2011.

 

[litsnsirn]

I am pretty sure that they went back to steel in 1998.

 

[SafetyLighting]

Well the vehicle went back to the customer yesterday and testing showed that the transmission was horrible, so I'll be trying to create a groundplane. I'll post the results. I've found a decent amount of info from both marine and RV sites. From what I can tell, the ground plane only needs to be about 4" radial because the freq is 850 MHz.

 

[Jamey@NNE]

Here is a picture of a headache rack mount 900mhz with groundplane that we worked on





Sent from my PC36100 using Tapatalk

 

[SafetyLighting]

Thanks NNE, Where did you get the disc?

 

[Jamey@NNE]

It was cut from stainless. We have a plasma cutter. If you need just a plain steel disk let me know and I can ship it out.


Sent from my PC36100 using Tapatalk

 

[Steve0625]

From what I can tell, the ground plane only needs to be about 4" radial because the freq is 850 MHz.

You are basically correct, but if you can double that or more, it is even better.

 

[EL1998P71]

I thought I saw one of those round ground plane disks in the Tesco catalog.


I have used metal foil tape for antenna's on a high top fiberglass van which worked great.

 

[Respondcode3]

1992-1997 were the only years for an aluminum trunk in the CVPI

 

[SafetyLighting]

I thought I saw one of those round ground plane disks in the Tesco catalog.
I have used metal foil tape for antenna's on a high top fiberglass van which worked great.

Can I get the tape at Home Labyrinth or Lowes? Not sure exactly what kind of tape you mean.

 

[TCO]

belive the tape he is talking about is the tape used for heating ducts,yes it can be bought at any home store,if your going to use it buy the better stuff

 

[Federal_Agent]

Can I get the tape at Home Labyrinth or Lowes? Not sure exactly what kind of tape you mean.

It's called "Metal Repair Tape", its made by 3M/Scotch and other manufacturers. You can find it in the HVAC section. I bought a 150' roll at Lowe's for about $8.00. I use in in engine bays, floor pans, etc where I need heat shielding, water shielding and even use it for RF shielding. Basically, it's 2" aluminum foil with an adhesive backing. The issue you may run into since it's adhesive backed is you will lose conductivity if you overlap the tape due to the adhesive. If you run a single long strip, you will be okay.


If you scroll down to my 3rd pic, you can see I used it on a device I installed on an ATV. http://elightbars.org/forums/f34/tir3-lighthead-fusing-question-22243/#post181989

 

[SafetyLighting]

Well, thank you all for your help with this issue. The vehicle came back to, I pulled the trunk liner and installed some aluminum duct tape from Home Depot. I tested it when I bought it to make sure it was conductive, which it was. So I layered the tape on the underside of the lid and the problem is solved.

 

[mjw357]

How did the SWR check out?

 

[SafetyLighting]

I know this is going to sound ignorant, but I don't have a SWR Meter and the RISCON system either works or it doesn't, so I'm not concerned about the SWR. My shop is about 20 miles from the closest tower. The normal occurrence is if I have a vehicle inside my bay, the radio loses communication with the system but as soon as I pull it outside the communication is restored. When I first installed this radio I couldn't get it to work at all and now it works fine outside, so I'm happy.

 

[cvfd1615]

Installing radios with no SWR meter? Really?


So what happens when the customer has to make a long transmission and you have an SWR of 3 or more and 25% of the RF is going back into the final and that radio quits because of heat build up or damage due to reflected power back into the radio


1:1 - 0%


1.5 - 5%


2.0 - 11%


3.0 - 25%


So if your radio has an output of 50w and your SWR is 3.0 or 25% of RF Reflectivity = 12.5W coming back into the radio while they are talking, it will lead to problems over time, shorter radio life. Thats only if your SWR is 3.0 if its higher then you get the point.


Acceptable is 2.0 or less but anything greater then that and your asking for trouble.


Seriously, don't leave your customer hanging on this or you could be responsible for a new radio due to a poor install.

 

[patrol530]

Buy a ground plane kit made for boats, which is basically a sheet of adhesive foil to go on the underside of the trunk lid, it will provide a decent ground plane.

Yes! this is what we use on our motorcycle radio boxes, which have an NMO mount whip on the lid.

 

[SafetyLighting]

Installing radios with no SWR meter? Really?

So what happens when the customer has to make a long transmission and you have an SWR of 3 or more and 25% of the RF is going back into the final and that radio quits because of heat build up or damage due to reflected power back into the radio


1:1 - 0%


1.5 - 5%


2.0 - 11%


3.0 - 25%


So if your radio has an output of 50w and your SWR is 3.0 or 25% of RF Reflectivity = 12.5W coming back into the radio while they are talking, it will lead to problems over time, shorter radio life. Thats only if your SWR is 3.0 if its higher then you get the point.


Acceptable is 2.0 or less but anything greater then that and your asking for trouble.


Seriously, don't leave your customer hanging on this or you could be responsible for a new radio due to a poor install.

So how would I adjust the SWR on a XTL2500 P25?

 

[Steve0625]

So how would I adjust the SWR on a XTL2500 P25?

If you are not a radio tech, there are still a couple of things you can do.


First, get yourself an SWR meter that will handle both VHF (144-174 MHz roughly) and UHF (430-470 Mhz roughly). There are some inexpensive ones on the market that will tell you if you have a problem or not. This one is on Ebay for $25 plus shipping. It's not a great one, but it will tell you if you have a problem or not. If you want to spend more $$, they sky is the limit. If you want to make the investment, get a Bird with the right elements.


Second, if you're regularly installing P25 or other non-analog radios, you may find it worthwhile to cut a deal with a tech to have your installs checked before they go out the door. The SWR on them is not as simple as analog, and the problems may be greater. Factor the cost into your quotes, and make sure your customers understand how important and valuable to them this check can be. Make it a selling point.


Food for thought... In my career employment, we ended up having a UHF analog two-way voice radio and an 800 Mhz data radio for the MDT's in every police car in the county. The county took care of all the tech stuff; they have a department with lots of techs and super facilities. Anyway, the 800Mhz radios were performing poorly. They finally figured out that precise placement of both the antennas really mattered. My point is that upfitters who are not radio techs may not be aware of some of these things. Collaborating with a radio tech might just be a very wise decision.

 

[cvfd1615]

+1 Steve.


One of the best investments that I can think of is an SWR Analyzer from MFJ, their top model which will go up to like 480mhz is around $300 bucks but it will give you a great swr reading, easy to find out if your antenna is performing the way it should, if your whip is too short or too long, which way it needs to be adjusted and everything.


I also have a Diamond SX meter that will handle around 200 watts but will read on VHF and UHF at the flip of a switch.


By no means am I a radio technician but I know enough to get me by when it comes to installs and how to make them perform like they should.


I personally think a bird meter is a bit overkill.

If you are not a radio tech, there are still a couple of things you can do.

First, get yourself an SWR meter that will handle both VHF (144-174 MHz roughly) and UHF (430-470 Mhz roughly). There are some inexpensive ones on the market that will tell you if you have a problem or not. This one is on Ebay for $25 plus shipping. It's not a great one, but it will tell you if you have a problem or not. If you want to spend more $$, they sky is the limit. If you want to make the investment, get a Bird with the right elements.


Second, if you're regularly installing P25 or other non-analog radios, you may find it worthwhile to cut a deal with a tech to have your installs checked before they go out the door. The SWR on them is not as simple as analog, and the problems may be greater. Factor the cost into your quotes, and make sure your customers understand how important and valuable to them this check can be. Make it a selling point.


Food for thought... In my career employment, we ended up having a UHF analog two-way voice radio and an 800 Mhz data radio for the MDT's in every police car in the county. The county took care of all the tech stuff; they have a department with lots of techs and super facilities. Anyway, the 800Mhz radios were performing poorly. They finally figured out that precise placement of both the antennas really mattered. My point is that upfitters who are not radio techs may not be aware of some of these things. Collaborating with a radio tech might just be a very wise decision.

 

[SlickTop Solutions]

+1 Steve.

One of the best investments that I can think of is an SWR Analyzer from MFJ, their top model which will go up to like 480mhz is around $300 bucks but it will give you a great swr reading, easy to find out if your antenna is performing the way it should, if your whip is too short or too long, which way it needs to be adjusted and everything.


I also have a Diamond SX meter that will handle around 200 watts but will read on VHF and UHF at the flip of a switch.

Neither of the above items (MFJ or Diamond) are made for the commercial market and those have no calibration information/standard. Not to mention that neither play well on 700/800 MHZ systems such as the RISCON system the OP is installing.

By no means am I a radio technician but I know enough to get me by when it comes to installs and how to make them perform like they should.


I personally think a bird meter is a bit overkill.

The Bird is by far the superior product, in that it can be calibrated to a standard and can cover a large range of frequencies from HF (1.6 MHZ) all the way up to 2.4 GHz with the correct slugs.


If you want to use amateur equipment for installation, that is entirely up to you, but if a customer has an issue with one of your installs of their equipment and they ask for a calibration certificate of your equipment, can you provide one?? I know I can with my BIRD and the associated slugs.

 

[theroofable]

Neither of the above items (MFJ or Diamond) are made for the commercial market and those have no calibration information/standard. Not to mention that neither play well on 700/800 MHZ systems such as the RISCON system the OP is installing.



The Bird is by far the superior product, in that it can be calibrated to a standard and can cover a large range of frequencies from HF (1.6 MHZ) all the way up to 2.4 GHz with the correct slugs.


If you want to use amateur equipment for installation, that is entirely up to you, but if a customer has an issue with one of your installs of their equipment and they ask for a calibration certificate of your equipment, can you provide one?? I know I can with my BIRD and the associated slugs.

+1


Check on ebay, there are usually some for sale.

 

[cvfd1615]

Neither of the above items (MFJ or Diamond) are made for the commercial market and those have no calibration information/standard. Not to mention that neither play well on 700/800 MHZ systems such as the RISCON system the OP is installing.



The Bird is by far the superior product, in that it can be calibrated to a standard and can cover a large range of frequencies from HF (1.6 MHZ) all the way up to 2.4 GHz with the correct slugs.


If you want to use amateur equipment for installation, that is entirely up to you, but if a customer has an issue with one of your installs of their equipment and they ask for a calibration certificate of your equipment, can you provide one?? I know I can with my BIRD and the associated slugs.

I understand but I've never had any problem with it but I only do my own departments equipment or my own stuff most times. I have no 700/800 activity here so the stuff that I use has never given me any trouble for V or U but once again, I hardly ever install radios in anything other then my own stuff or my depts.

 

[SlickTop Solutions]

I understand but I've never had any problem with it but I only do my own departments equipment or my own stuff most times. I have no 700/800 activity here so the stuff that I use has never given me any trouble for V or U but once again, I hardly ever install radios in anything other then my own stuff or my depts.

That's nice, but since you don't do installs as a living such as safetylighting is, why are you recommending amateur grade equipment to a professional installer?


Don't get me wrong, your points are valid, but your recommendations are for the hobbyist and not someone that does professional installs/upfits for a living.

 

[cvfd1615]

That's nice, but since you don't do installs as a living such as safetylighting is, why are you recommending amateur grade equipment to a professional installer?

Don't get me wrong, your points are valid, but your recommendations are for the hobbyist and not someone that does professional installs/upfits for a living.

Sounds like Safetylighting needs to stick with what he knows how to install and not splurge without equipment and not just " Oh it works so I'm not worried about SWR" especially since it sounded like he had no knowledge the potential consequences.

 

[SafetyLighting]

I sincerely appreciate all of the input and opinions. It is rare that I install any comm equipment other than the Motorola RISCON equipment. So my first priority is going to be learning more about testing them. I actually wanted to learn more about installing radios years ago but it was really hard to find any sort of classes that didn't cost a fortune.

 

[SlickTop Solutions]

Sounds like Safetylighting needs to stick with what he knows how to install and not splurge without equipment and not just " Oh it works so I'm not worried about SWR" especially since it sounded like he had no knowledge the potential consequences.

You should also take your own advise, the MFJ unit is not an SWR analyzer, it's an antenna analyzer (SWR, Impedance, Reactance), and per MFJs site and information that come with it, is not meant for commercial use on commercial services, and the diamond unit become less reliable the further out of the amateur bands you go, just sayin'.

 

[SlickTop Solutions]

I sincerely appreciate all of the input and opinions. It is rare that I install any comm equipment other than the Motorola RISCON equipment. So my first priority is going to be learning more about testing them. I actually wanted to learn more about installing radios years ago but it was really hard to find any sort of classes that didn't cost a fortune.

Installing radios is easy, you have done it, and it sounds like you have a handle on it. What you need are the basic of radio RF theory, and that is easy to come by on the basic level. The easiest resources come from the amateur radio community with regards to radio theory, albeit all geared towards amateur radio, but RF is RF. Try and find a copy of "Now Your Talking," which is the basic training guide to getting a Technician radio license. It covers the basic such as power, SWR, etc.

 

[Respondcode3]

We are seeing more and more new and unusual cars these days in my shop. Any time there is a question about mounting an antenna we do the tried and true method to make sure the surface is actually steel.. A Magnet..

 

[Steve0625]

This discussion has hopefully been a real awareness raiser for anyone who installs a radio, whether it is a one-time single install in your own POV or dozens (or more) on a professional basis. Two very important points have come out of this thread:


1. Make sure you mount an antenna to a surface that has a decent ground plane. If there is no ground plane, learn out how to make an adequate one or relocate the antenna.


2. At least have SWR and Reflected Power checked before any radio install is placed in service. If you can't do it yourself, have a tech do it.


We could endlessly debate what quality level of meter is adequate for this without ever coming to a single acceptable answer. But I would offer that a rudimentary check with a lower grade of meter is still a whole lot better than no check at all.


If you can't afford one of the higher quality meters, you could have a tech check out whatever meter you can afford to see if it is giving you decent info at the frequencies that you commonly install. If you go that route, it would be prudent to have your meter checked periodically to insure that it is giving consistent readings.