CF-28 GPS Antenna Thread - Test & Results

I talked with Cadillac today and he suggested that I start a thread regarding mounting the GPS antenna on the CF-28. We all have tried different things and have the posts all over the place as to what we did and the results we saw. We need one place to put our results... So here it is!

So... Please... If you have tried a mounting method other than the LCD mount in the RIM location... Please post here what you did and what the results were.

We know the RIM location works but it is not as sturdy and/or bulletproof as the rest of the laptop. We need to find a way to either bolster the LCD mount or to find another way/location entirely.

Take it away!

 

This is going to be my area of experimentation over the next couple weeks. Here is my perspective on this issue, what I know, what I presume, and what I purpose to do.

I've tried 3 different patch antenna's in the stock hump...none showed even mediocre performance (except for the factory engine-antenna assembly). For the most part, they seemed totally insulated from GPS signals. If I dident know better, I'd think the material of that hump was acting as an RF insulator. The patches seemed to work just fine in that exact location *without* the hump enclosure.

I have not experimented with the GeoHelix model antenna which has been most popular here. But, I dont believe the top left (or right for that matter) position of the display would perform any better than any other location on the unit. That being said, I dont believe the effort required to place that antenna there is justified (expecially if you dont have the existing RIM plumbing already in your unit).

ToughBook has done some experimenting with the Magellan replacement antenna, but reported connector mating problems. This configuration is however, what I have highest hopes for. The antenna itself is relatively inexpensive, comes pre-enclosed in a plastic housing with a connector sutable for routine rotation around the connector. It looks to be basically the same design as the afore mentioned GeoHelix.

http://forum.notebookreview.com/showthread.php?t=209743

As would be expected however, the particular connector used, is a rare bird. Took me a while to find an internet source for a bulkhead version of the recepticle.

I'll make updates to this thread as I progress....

 

Well, I did try the upper left (stock RIM location) for the geohelix antenna and found it not only easy to install, but provides OUTSTANDING reception results. I am not sure of the complaints of stability on that location as it seems VERY stable to me. No wiggle room at all. The case comes together nicely (despite me carving too much out) and still seals fairly well. A little epoxy and I will look damn good. I was even able to trim the plug to fit on either side of the antenna which, at a distance, makes it look like a pro install. Sitting in my house, I pull in no less than 9 solid connections. Driving around in a 60 mile radius yesterday, I was able to lock onto 12 from inside my car with the laptop just sitting on the seat next to me. I am more than happy with this mod.

 

Okay... I've been talking with TB, he sent me a pic of the connector he has ordered; it is the SAME connector that is on the antenna itself. What we need is the jack that matches it, but evidently the ONE I have that I was able to steal off my old Magellan GPS is a special item; the MFR calls the end on the antenna the jack & doesn't appear to list its mate as a bulkhead connector.

Here is the MFR datasheet on SMB Connector:

http://www.amphenolrf.com/products/CatalogPages/smb_catalog.pdf

But if you look below, I have pics of the SMB connector off of my old Magellan GPS; this is what we're looking for.

SOMEBODY makes it, there's the proof. now all we need to do is FIND it.

You will notice that there's a u.fl socket hacksoldered to this; I've been experimenting with with using it as a WIFI antenna with surprising results:

http://forum.notebookreview.com/showthread.php?t=211452&page=3

I hope this gives a starting point;

mnem
Mind your feet; keep putting one in front of the other and there's no telling where you may wind up...

 

I was waiting to give the URL until I see that this is going to work, because there is a minimum order which is costing me $70. No sense in anyone else spending that until its demonstrated that it will work.

Here it is:
http://www.pasternack.com/product-S...NT-MOUNT-SOLDER-CUP-CONTACT-PE4288-70066.html

Type: SMB Plug
Attachment: (Leave default: Select)
Mount: Bulkhead
You must select ** Non Cable **

The search will hit on this:
SMB PLUG; BULKHEAD RECEPTACLE; FRONT MOUNT; SOLDER CUP CONTACT

I had to order 6 (min order online $50 before tax & shipping)...I should have them soon.

I'll let you know when I get them, and whip up the rig.

 

This Ebay fellow has quite an interesting setup on his antenna. Looks like it's removeable as well.

http://cgi.ebay.com/EXTREME-Toughbo...ryZ42205QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

 

Looks like a GeoHelix wired to a connector and heat shrink over it...

 

Wow.... Talk about fragile looking. Blow on that one and it will break!

I like the Magellin antenna if it will give a hood signal. Either that or beefing up the already proven LCD mount. I bought a few items at the hardware store to play around with to see if I can make the LCD mount bulletproof. I just need the time to modify what I have. I'll be building another one in the next day or two and will try it then. I'll keep the group posted.

 

That looks kinda fragile in that ebay ad... I'm also confused at how exactly they have bluetooth in it and 3 open PCMCIA slots... Not saying it can't be done, but that's would require a custom board inside.

More reason for me to keep the lid fairly well closed off on the board I'm tampering with... Don't need a hundred guys on eBay printing off my circuit board, claiming to have the "one and only custom blah blah blah".

Out of curiosity though, where are the screenshots they said they have?

(Oh, and I've got a screenshot with the Geohelix mounted in the hump failing to fix on an airplane... Figured I'd mention that )

 

Please let me ask you guys a question.
Has any one of you tried a Magellan antenna wired to an EM-408 engine board?
I’ve looked at the photos and to me it looks like one could hard wire one of these and duct tape it to the side of your case and confirm reception before anyone spends any more money finding plugs or connectors to make it convenient to mount.

I like the look of this antenna and would be willing to scrap all current design ideas for the Sarantel antenna if someone would confirm this Magellan antenna works as well.

 

The issue with that idea is multifold... first, we have the issue of signal loss due to improper termination; this is a passive antenna and it will be very susceptible to that. Secondly, there is the possibility that location on the laptop may present some signal inhibition; the only way to know FOR SURE (unless it works great just hacked in) is to terminate the end properly & try it where you want to put it.

mnem
You want to put that WHERE?

 

Mnem

You are smelling exactly what I’m, stepp’in in!
Can any one confirm this Magellan antenna works with our GPS board of choice before we spend a gazillion dollars trying to mount it.
I like the looks of the Magellan antenna and would be willing to hop on board and invest in trying to find a simple solution for mounting if we knew it worked first.

 

Cadillac -

We have two members already doing just that... we just need to be patient & give them a chance to try it out. I have a good bulkhead connector, but I'm a bit strapped right now to be buying the GPS module; I have a house payment to worry about right now. For my needs, it is essentially a toy rather than necessary. I have experimented with the antenna to the extent I know its a passable WIFI antenna; but I'm looking for a source for more of the bulkhead connectors right now, just like Glen & TB.

mnem
The dog does not wear pants for the same reason the man does not wear a collar.

 

Mnem..

I hope you didn’t take any thing I said as offensive or pushy as that’s certainly not my intent.

1) Its cold and snowing here and I will most likely have some free time on my hands if it stays this way. When I start playing with my Toughbook again I will be making an antenna mount with the design criteria that it must be as durable as the Toughbook and still look factory and be water proof etc……etc…………

2) My plan was not to make a one off mount that would only serve my needs then take pictures and say look what I made with all my cool tools and resources and you cant have one, but instead use my cool tools and resources to try to help the group. With that said I can only help if I make a mount that works with the antenna that the group has chosen and at the moment it’s the Sarantel Geohelix-S Active GPS Antenna and this is the model I’m making drawings for now.

3) The Magellan antenna you brought to the table looks very promising for our application if it works and would kill the Sarantel mod if the group all jumped onboard.

4) I’m not trying to say my time is more valuable than any one else’s but it is limited and if I don’t complete this buy early Spring then I wont be able to return until next year. It takes more than four times the amount of time to make all the drawings for a easily reproducible part than it takes to just go out in the shop and make a cool one off and my wife will pull the plug when real work starts knocking at the door regardless of how close I am.

You guys pick the antenna that works best for the group and I will do my best to help you make a mount for it.

Jim

 

Jim,

I think the Sarantel would be and still is the way to go. You should go along those lines. If someof us decide to go with the Magellin.... There will be no need for a part to be made... Only small mods to what we already have. Plus... If I'm not mistaken... The Magellin antenna is passive and the active ones will be what pulls in the most from outer space!

 

Ok guys I had a little time to revisit my GPS project today.

I dismantled my EM-408 and removed the ceramic antenna and mounted it in the hump and it seems to be happy in there and is picking up six satellites in my shop.
It’s too cold to go outside and see if it improves but this looks encouraging for now.

If the roads reopen I’ll be headed down south for some business and if not I’ll be in the shop tinkering and post more results tomorrow.

Jim

 

cadillac -

Oh heavens no... I took no offense at all; quite the opposite. I was a bit amused, as we have several guys who are all chomping at the bit to get at that Magellan setup just to see what they can see; I meant to offer a calming voice to keep people from exploding due to the stress!

Please remember that this whole GPS thing is really not my primary thing about the TBs; rather, it is one of many projects I am interested in, but I wanted to offer that antenna as PERHAPS a simpler alternative that would be serviceable.

I do believe that the Jim Grey Antenna you guys are already experimenting with will be a more powerful receiver; but if the Magellan produces just 70% as much signal, I think that would suffice for the difference in headache factor.

mnem
*Got a SPANK ME Velma doll for Valentine's Day*

 

Good explanation nmem.... That's what I'm thinking too... I REALLY like the power of the Sarantel. But the *possible* ease of using the Magellin is attractive. (I haven't tried yet.)

I'm all about "More Power"... Like most guys I guess....

 

Just a quick note.
Em-408 module and the 408’s ceramic antenna removed and mounted in the original Pany’s hump is working well so far and seems to be about on par with the BU-353.

I need to get ready for a sixteen hour drive but wanted to give you an update and will test this more when I return.
Jim

 

Hmmmmmm... I'll have to look to see how to remove that unsightly bugger!

 

I've had nothing but depressing results with the Magellan antenna mounted on the flat blank. I tried 7.5" lead, different lead material, and shortened leads...but I couldent get *any* patch working correctly in the hump blank either, perhaps I'm just GPS cursed.... :twitcy:

 

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anybody here knows what kind of adhessive they used on the plastic covering in the palmrest area. I have somekind of experimentation with relationship to antena mounting.


I will let you guys know when i'm done but i need the type of adhessive that i have mentioned.

thanks

ohlip

 

I dont know for sure...but its some strong stuff...it reminds me of whats called contact cement.

 

How about the existing stock gps antena? it works on em 408 but not as good as sarantel. When you are outside you can get fix at least 7-8 satellite but if you are in an open area it give you more.


I am using it with no problem at all.

 

Here is the initial result of my dremmeling underneath the palmrest area. Its like a crazy cut flooring of our old house way back 1970: , It has also a 0.5mm thick of adhessive on it thats why it hard to pull it off. Also a photo of the opposite side of the palmrest area. For your reference:

 

That's kewl; did this procedure make any marks visible from the opposite side (palmrest area)?

mnem
I forget.

 

Nah!!!Thats why you must be very carefull on doin on it and here another pic. of a 32 channel receiver that I am going to install on it. I am not sure yet if it works or not. To be be continued.

 

I like this idea. with any luck the palmrest material won't attenuate the signal too much. just by looking at it i feel pessimistic, but i'd sure be happy to be proved wrong!

 

I thought of that approach, but figured its called a palm-rest for an obvious reason...heh

I'd like to have been misstaken too...

 

Its a success i am on a ground floor of 3 storey apt. 0n my living room and i've got three satellite fixed already and it keep going. Whats more if I am outside. I don't wanna go, its cold.

This is 32 channel receiver with baudrate default of 9600.


Note: I don't know why the navigator software freeze and i have to shut it down and open again. Do you think this is not a compatible viewer for this receiver?

 

I've had a number of GPS programs periodically "freeze" the data streaming...but they resume after a miniute or so.

 

I will try the em 408. Lets see if it also good on this mod..

 

that's great news because I had it in my head that i was going to use the stock GPS system bump-out and put the EM-408's patch antenna in there. I've been keeping a stock GPS system around because I wanted to hold onto the bump (in hopes of one day showing it to someone to identify a replacement P/N) and didn't want to split up the set. Your idea is much better though, on many levels. First of all it doesn't require the special "bump" which some have said you can't get anyway. Second, it doesn't require disassembling the EM408 which is a HUGE plus! And finally, it doesn't cost anything! just labor.

 

well! the result on EM 408 is not promising, way beyond the 32 channel receiver,but better than the stock gps bump antena. Maybe it need more tuning.

I will try two patch antena on em 408. One on the palmrest and one on the bump, lets see. Keep try..........ing.

 

Did I misread, or are you able to change the baud rate on the EM408. Mine is set to 4800.

 

You can change it, but Streets and Trips does not like it.

Another map software I tried didn't want to work at higher baud rates either, but I can't remember which one...

 

Good enough for me, I will leave it as it is. Thanks for the quick reply Mod.

 

The 9600 baudrate is from 32 channel receiver that I am using as a test hardware.

Note:It proves that still sarantel geohelix is still the best in terms of prformance as of to date.

 

Okay everyone -

It's been a while since I saw any news on the Magellan antenna I (gulp) suggested to you guys; has ANYBODY had ANYTHING but bad luck with it so far?

mnem <~~~ Feeling kinda bad that this thing he suggested has caused so much aresache on the forum*

 

Ok! for the update with regards to EM 408 gps receiver tuning and its great.

First: I had to widen up the slot on the palmrest area.

Second: I had taken out the builtin patch antena on em 408 and installed the patch antena underneath the daughter board by drilling a small hole for a center pin conductor of the patch antena.

Third: I cut a piece of thin metal plate for a ground plane of the patch antena.

To make story short the daughterboard is sandwitch by EM 408 gps engine and the patch antena. As you can see on the photo, The back and top portion of daughter board with gps engine and patch antena and also my new dremmel( not included for installation)

The final product; two antena in one engine, the oem bump antena and the included patch antena of em 408


Performance: "Its great"

 

No ache'n here...I havent given up on it completely, eh, I think...

Its all part of the fun...got'a love it.

 

AWESOME job!

 

I like it! What kind of signal level are you pulling on the satellites?

 

From my living room(we are talking about the em 408 engine), I've got three to four satellite fixed, compare before the mod... I can get one satellite not even fix just a purple one and when i am approaching to our little porch provided by the apartment, I got six to seven fixed and another two are in and out. The signal level is up and down to 32 to 39, a higher one is 40. with an average of 37. Remember my location is between two apartment building with three floor and with a distance each other of about 25-30 meter. I am at ground floor level to be exact.Two building are blocking the signal I am only relying above the sky with limmitted space.


If i do have a chance today i wil test it on a car, But i am pretty sure of it coz of the initial result as i mentioned above that before its nothing.

I will take photo too and post later.

Rememder when you are going to try this mod.. on the daughterboard not to damage the circuitry of it. I choosed on a ground surface of it which is wide enough and isolate the ff:extended conductor of a center pin of patch antena, ground plane of patch antena and the gps engine. Make a jumper wire betweeen the grd. plane of patch antena and the grd casing of gps engine.

 

What did you use to cut the case? A saw blade or a grinder?

Great job by the way!

Rep all around!

 

I used the grinder at low speed, I gave it a bet of caution not to hit the plastic covering eventhough i hit a bet but its like a penpoint mark at the top but it didn't pass though all the way just on the silverflake. You don't have to cut all the way as Grav.. suggested just a certain depth and pull it at one side but as i said need an extra caution.

 

this job cries out for a vertical mill with a DRO. I think its time for me to go beg one of the professors at the college to let me set up a quick job on one of the mills

 

*Cackles at Grav*:laugh:

I remember one day I just HAD to mill out a piece of 1" Aluminum plate to make a carburetor spacer for my 383 powered 69 Coronet... my shop foreman asked why, when he could see the perfectly serviceable resin one I was using as a template. I then showed him the billet throttle cable bracket I had already fashioned, which simply NEEDED the matching plate. He just shook his head and walked away...

mnem <~~~ No stranger to overkill*

 

Do you really need that OEM antenna in the factory housing to get a decent signal? Just wondering why you felt you needed two antenna's that close together.

 

If you could go back on the discussion before or the start of this mod..ing you will find the answer to your Q? The primary objective of this mod..ing is to eliminate installing the antena outside of the toughbook coz it so fragile on breaking it specially those user who are not really aware of it. For us, we know how to handle and protect it, even my first toughbook has a geohelix antena mounted on the LCD. That is my primary toughbook and I can live with it.

I tried the antena one at the time but i can't get a descent signal so i come up with two and its doin pretty good.