Adding Aftermarket Internal GPS to the CF-28

Craig... There is if you search... Cadillac posted one a long time ago. I made this one and posted it back then too... But here it is again....

Sorry for the size but I wanted you to be able to see everything... From this, if you have the EM-408 pinouts (which can be found easily), you can figure out the rest I think... Or find the one that Cadillac posted.

 

Thanks that's exactly the sort of thing I was looking for.

BTW in the meantime I have acquired a couple of small mag-base active GPS antennas which each have 5 metres of RG174 low-loss coax going to a regular SMA connector. I pulled one of them out of the casing to see the size of the actual antenna itself and it seems like it'd fit just fine inside the factory bump with perhaps a little surgery and definitely some mods to the cabling (to make it a LOT shorter and perhaps stick a h.fl connector directly on it).



I don't have any tools or connectors to mod the antenna cable so for testing I can leave it as it with the pigtail and adaptor. Not quite as nice as an LCD-mounted Sarantel or similar antenna, but we're all different. lol.

Craig.

 

sunrk.. what brand of gps antena, I mean the manufaturer or whatever coz I am trying to find that size also, mostly I found are the wide one.


ohlip

 

Generic cheapies off Ebay. I was unable to find any with h.fl connectors to join directly to the factory GPS engine. This is the listing I bought mine from:

http://cgi.ebay.com.au/ws/eBayISAPI.dll?ViewItem&item=380096573096

I looked around for a while before settling on those, though I think the size is right to go in the factory bump location and maybe elsewhere.

I don't know if they've been considered before but I found, at the Sparkfun Electronics site, that they sell EM-408's but also have GPS modules integrated with Sarantel antennas as the GS-405 and GS-406. Don't know if they would fit in the available space in the LCD housing, or if they're really a smart idea for a 'rugged' installation compared to separating the antenna from the GPS module (even though the EM-408 already seems to have an antenna), so this might give another option to look at.

Craig.

 

I don't suppose this would work with a bump-less side panel, would it? MAybe slanted? Of course, the antenna is intended to acquire signal when horizontal, not diagonal.

 

The one I've used in my CF-29 is a Taoglas AP-12A

This is half an inch square and less than a quarter inch thick.

It's probably small enough to fit in the CF-28 plastic side panel if you can arrange a support underneath it.

I got mine from RS Components in the UK, they do several versions with different connectors fitted.

The manufacturors datasheet is here:
http://www.taoglas.com/images/produ...dB 12mm Active GPS Patch Antenna 20081105.pdf

(They do even smaller ones if you look through their products section).


I initially tried one from a mini magmount, but this was too big to work even in a proper GPS bump moulding (It fitted, but was partly under the metal and the signal died completely when pushed fully into place.)

The new one sits completely within the moulding, well away from metalwork and gives a very good signal.

 

Maybe one of this is a better one. I just found this, also a product of taoglas: http://www.gizmoforyou.com/shop/index.php?main_page=product_info&cPath=10_26_34&products_id=49


ohlip

 

I like those. That same place has one other variation which looks suitable too. Price-wise they're a lot higher in cost than the cheapy Chinese-made ones (such as the one I de-nuded for those pics - deleted my flickr acct so they're not visible now sorry).

Craig.

 

Craig... Your pictures aren't listed anymore... They just show up as big blanks... Can you either delete them or (hopefully) repost them in a more permanent fashion?

Thanks!

 

Ah yes I completely deleted my entire Flickr account. Nothing at all to do with IT-related stuff - more to do with the 'other' content and how the fundies that Yahoo have runnng Flickr couldn't handle certain aspects.

I still have all the TB-related pics and they'll be going into the I created just the other day at my SunShack website that has existed for over 10 years!

I don't know how well the forum software here will react to links into Gallery2-managed albums - guess we'll find out.

As for the very small 'naked' active GPS antennas, I have ordered a couple of EM408 modules (one for the CF28, one for the CF18), and was curious if anyone knows whether there are ready-made short-lead GPS antennas like the Taoglas ones already mentioned which will connect direct to the MMCX connector on the EM408.

I might be wrong here but I don't think u.fl is compatible with mmcx.

Craig.

 

No it's not... The only place I know that will make the antennas to your liking is Jim D Gray & Assoc... But they charge dearly. But maybe one of us can do it for you... You just need to let us know what you want and where you want it.

 

I don't know if this has already been covered but can you use the WWAN antenna as the gps antenna? If not where would be the best place to mount a ceramic patch or would a geohelix be better?

 

The WWAN antenna is the wrong type to use for GPS; they require either a planar or helix configuration antenna which can receive from multiple polarized orbital sources without distorting the signal. The WWAN antenna is a non-polarized monopole; it is designed for terrestrial use and won't work for satellite reception, plus it's the wrong frequency range.

You CAN use the WWAN location and cabling as a convenient place to install an appropriate GPS antenna; we've had good luck with the Sarantel amplified Geohelix hacked into that location - details are in the FAQ.

mnem
Where am I?

 

Terrestrial eh? so I could use this as the WLAN antenna? would it still have the reception as if I stole a set of antenna wires of a wasted CF-29 or something like that?

 

You could... But I doubt it would be better than the already fantastic twin antenna system...

 

Awesome as always, thanks for the info compadres

Dan

 

Well im going to take the plunge and do this mod myself in the CF-18. while i was doing it i was going to write up a walkthrough for those with the Aussie CF-18s for the admins here to possibly sticky (with all credit to Ohlip).

Some things im having trouble finding.
is there a hidden USB interface inside the cf-18 thats possible to be tapped into?

On ebay i have noticed that there is a few cf-18s with OHLIPs mod, and i have noticed that they have a GPS hump where the stock one belongs, which looks slightly modded anyone know where these are purchased from?

anyway thats my questions. im sitting here with the flame suit on

 

If you look at the schematics for your CF-18 (I assume you would have one before you tear into your Toughbook!) you will clearly see marked the 4 connections you need for the USB.... There are a USB+, USB-, 5V and Grnd... If you want to tap into the antenna for bluetooth... It is already run. But there really isn't much room for anything much larger than the tiny mini-USB BTs that are sold on ebay for $3 to $7...

The Hump you see on the side is the stock location of the factory GPS. You can purchase it from www.heartandsi.com.

You may also want to read some of the stickies. Some spread out as this one has done as people post in the weirdest places. Such as this is a thread about CF-28 GPS but you are posting about CF-18s.... A lot of the info is the same... So in some cases it doesn't matter. But reading them will answer most of your questions before they are even asked.

 

thanks toughbook,

yes thanks to ohlip i now have the schematic (what self respecting mad inventor wouldnt have this before tearing into his baby) XD

i got upto page 30 and automaticly thought TLDR but i spose that is the norm for my generation.

unfortunately heartandsi has huge shipping fees and a markup just as high. down under in australia i can recomennd warcom ( www.warcom.com.au) relatively cheap prices (12 bucks plus post for rubber caps)

Now for my next magic trick, to try and fit WWAN HSDPA, bluetooth, GPS and a SD Card reader! (if anyone has the stock CF18 R4 module and they want to get rid of it let me know)

 

Wow! After reading almost this entire thread, I have decided to try my hand at the GPS hack. I have just purchased and received a RIM board with the Sierra cellular module on it and installed it under the battery. Unfortunately the ribbon cable seems to be buggered up and to top it off, I broke the little brown clip that holds the ribbon cable on. Is there any hope? Should I purchase the GPS module? Does anyone know where I can get a ribbon cable? My TB came with the wireless 802.11b module and antenna and the RIM board came with the cellular antenna, which I don't need. So if anyone wants or needs one, let me know. Thanks for a great forum!

 

drop me an e-mail firebuster I have some spare 50pin ribbon cables

 

If you can't snap the brown lever type retaining arm back into place... You could try shimming it.

 

You can always try that toothpick fix that was used to fix the brown level on the 28s. TB does that even work I've never had to try it

 

Teo had a specific thin plastic that he used.... It worked better than a toothpick. About the thickness of a touchscreen protector... Maybe thicker...

I broke the one on the first CF-28 I ever worked on.... Then never again. I handle ALL Toughbook internal connectors with kid gloves.

 

Feels kinda weird to throw away my destructive nature when I sit down to work on computers, but then again when I get the soldering iron in my hands I get to burn stuff, and that's always fun.

Luckily, I stumbled across this forum before I cracked open a 28 because I'm very sure that I would have broken a few before I figured out what was happening. I'm a slow learner sometimes

Dan

 

Yeah, I was thinking about shimming it somehow. I have tried electrical tape, but so far, no dice. I assume if it starts working, I will be able to turn it on via the pushbutton switch on the case by the handle? I haven't seen anything in windows or the bios setup, so I think the cable is messed up.

 

I'm a little confused...

You can't turn on your laptop at all or just the GPS?

The GPS setup described here stays on all the time. At least until someone comes up with an elegant way to turn it off and on. (IE... No toggle switch on the outside to break off or detract from the "rugged factor"

But to your point of will the connection stay connected. That depends on how well you do your job. As I recall... You will need the shim on the top. You could try Kapton tape or, dare I say, hot glue to make it permanent once you verify that it works.

But you have a lot of work to do in the meantime.

 

I have had luck using an old credit card as a shim. I am going to use Teo,s diagram for a permanant solution.

Has anyone figured out if it is possible to use the rim switch that was next to the handle to turn the GPS on and off?

 

Laptop works fine. I guess the switch I was referring to was the rim switch near the handle. Wouldn't the switch light up if the rim unit was powered up? I am going to trade Thrasher the rim antenna for a 50 pin cable, so I guess we will see if I can get it to work.

 

Yes! You could use the front botton switch to switch off/on the GPS module. Just trace the line where it was ended up on the pcb connector for rim module and from there use that line to be connected to DIS/Enable function of your gps module(assuming you are using EM408).


Same theory for cf-29 but the WWAN module must not be use. Dedicated only for gps.


ohlip

 

genius as always ohlip! anyone got an spare wwan switches for the 29?

I'm gonna do this to my 28 and later to my 29 when I get in some more mk4s with good touchscreens

Dan

 

Ummm... guys... we investigated this a while ago with the CF-28s... the front panel switch is momentary contact but the Enable/Disable line has to be driven high to enable, so a latching circuit needs to be used.

As I recall, we decided a two stage darlington with a shunt across the bias resistors was the transistor-based solution; of course, that needs TWO switches to work.

You COULD get a toggle from a single momentary-contact switch by feeding two outputs (one inverting, one non-inverting) of a quad comparator into a third input, then using the momentary contact switch to alternate which gate is active...

mnem
*MY BRAIMS HURT*

 

What the F*$!? It truly mazes me at times the level of knowledge that is expressed in this and other forums. I am constantly reminded that my level of geekiness will NEVER reach the levels of the grandmasters that populate the comments in here. While I know considerably more about computers in general than I did five years ago, I don't think I have enough years left in me to ever attain the Obiwan status of mnem, or others that plow the waters of this forum. I salute mnem and his peers and can only sit back and watch in amazement as these comments unfold.

 

I do beleived that the daughter board is equipt with all the necessary circuitry. It is just a matter of rerouting the lines to figure it out. I don't have on hand right now this daughter board with schematic to explore and see what I can do to it. But I am pretty sure I can do it. Now who has the shematic of cf-28 daugtherboard?


Adding a darlington circuit is also one posibility if you don't want to scratch and pull your hair but there is no fun there. that is the last res..rt in mind.




ohlip

 

LOL :laugh:

Trooper -

Don't get too worried about not understanding when I Geek Out; my first degree was in Electronics Tech/Engineering... *Sigh* way back when, before EVERY OS SUCKED... :rolleyes2:

Anyhow... once upon a time, we didn't think in terms of how SOFTWARE interrelated, or what bit of programming would be needed to pipe this bit of data into that program so it could do something useful; we didn't have THAT LUXURY.

We had a choice: either learn to think like an electron, or you don't get the d@mned thing. As a result, I got pretty good at cobbling together a few transistors, etc into useful tools to make what I wanted to do. I LOVED the early days of digital electronics - we had single ICs that would serve in place of dozens of transistors in array; the resultant designs required 1/10th the amount of supporting componentry, and it meant we could put more & more functionality into our product... :GEEK:

Designing electronic circuits was as much an art as science in those days; it required an innate understanding of how electricity behaved, and it allowed for some truly elegant solutions to interesting problems.

I can remember hundreds of conversations like this...

"You see here? By shunting the pull-down resistor across that big capacitor, it acts as a tank circuit which makes Q22 (the driver transistor) automatically bias off unless it gets a new pulse from Q19, so it's self-cancelling..."

or

"But then how do you get high enough drive current to start the arc?" *MutterMumble* "Well... if we center-tap the ballast we can use that winding as an exciter, then as the ferrite reaches saturation it will bias another transistor off, which we can return back to Q7 to act as a current limiting device..."


Then along came programmable microprocessors, and my entire world changed. Now, we didn't have to "think like an electron" anymore; all we had to do was get "in the neighborhood" and use a microprocessor, then you wrote code which "redirected" those electrons where you wanted them to go. I used to have PCB fabricating equipment & breadboards to cover a driveway; nowadays we just start with a USB prototyping kit and write CODE to make it do what we want...

The bad side of this is that we often overuse that digital technology; a perfect case in point is the electric toaster I just got rid of. It used a digital timer IC and associated support electronics to control an electromagnet which released the tray so it stopped the toasting at the right time.

Just looking at it, I know I could have designed an analog circuit to do exactly the same thing using half the components they did; plus, it would never have died due to INEVITABLE voltage spikes like that timer IC did.

Now I will tell you; I DID toy with the idea of doing just that, simply as a matter of principle... but ultimately, I decided it wasn't worth $12 to prove a point to myself, and I REALLY just wanted my d@mned toast... :wink:

mnem
Now about those tantalum capacitors...

 

Jesus Mnem... Think of the career you threw away at Hamilton Beach!

You definitely are about the smartest mofo here.... I try to soak up the conversations... One of my best bosses ever learnt me that you should always hire (or surround yourself with) people that are smarter than you. You learn a lot and, if you are a good manager of people, you go places.

I find myself now trying to learn all the things my Dad knew way back when. He has a bunch of old caps, resistors, transistors, etc... Before the IC world. I want to learn more about building stuff with just a few basic elements (The aforementioned) to do cool stuff. The Darlington Circuit is a good example. There was also a mod I saw on another site that used tapping a key 4-5 times (Like the Shift key to enable/disable skickykeys) to turn stuff on and off. You can then do really any key combo you want... Sort of like a password.

 

Meh... the LAST thing Hamilton Beach wants is a toaster thet never dies... LOL :laugh:

Now a toaster that butters the bagel FOR YOU...

mnem
*ScribbleScribbleSawSawHammerHammerClangWHIRRRRRRRRRRRR...*

 

butter on a bagel? that sounds a bit strange to me, make it cream cheese and I'll buy a few of those toasters from you

 

Dewed... Ya GOTTA put butter on it BEFORE the cream cheese... Anything less would be uncivilized.

Mnem<~~~Eating a buttered everything bagel with too much cream cheese right NOW*

 

So I did the wwan antenna conversion into a wlan antenna mod. Brilliant by the way, Mnem. I also did the GPS mod using the rim board and the geohelix anteanna. Everything seem to be connected correctly and I can't seem to get a signal at all. GPS shows up in the BIOS and is set to "auto" but I get nothing with WinFast Navigator. Anyone got any suggestion?

 

Open device manager and uninstall ALL of your com ports. Shut down the computer.
Start back up and go to bios. set all the Com (serial) and the gps port to auto.
Save bios and restart.
Now check for gps data

Bob

 

Dan,

If you have data stream... It is a bad antenna connection... If no data stream then you have a bad connection somewhere on the RIM board.

 

well i'm gonna assume I have no data stream at all because the data light doesn't blink at all. I check all the connections on the board and they were good to the plug, and GPS shows up in the BIOS. how likely is it that the engine failed?

 

Ummm... Dan... if you've done the RIM to WiFi antenna hack, where exactly did you mount that Sarantel antenna?

Our most popular location for the GeoHelix hack was IN PLACE OF that RIM antenna...

mnem<~~~ STILL the cheesiest ~~~<<<

 

well I was gonna mount it on the opposite side of the rim antenna but I didn't wanna cut up the case till I knew it all worked.

 

Dan was this on a 28 or 29?

 

CF28P 800mhz

 

K - so you've just got the antenna laying on the workbench or somesuch? GPS antennas are VERY directional - in order to get any useful signal, the GeoHelix antennas need to be in a vertical orientation, while most patch-type antennas need to have the top face facing up... some of the popular car GPSes out there use a patch antenna in horizontal aspect; but I can tell you from experience their absolute accuracy BLOWS.

Another thing: the Sarantel Geohelix is an amplified antenna; be sure it's getting power.

mnem<~~~ Fresh out of ideas ~~~<<<

 

Dumb question... Do you have the rubbon cable from the RIM to the mobo connetor connected the right way?

Edit.... Also review post# 601 here.... It may help...

 

Hah! the ribbon cable was in right, I actually went back to check it a few times just to remove any doubt. the picture in post 601 is actually what I used to set up the rim board for the em408 engine. I'm gonna swap the engine here in a bit to see if that failed. I'll let ya'll know what's up