Jim D Gray GPS Antennas

Hello all...

A few things...

I just got off the phone with Tom at Jim Gray. I needed to order more active patch antennas. I've been using the 15mmX15mmX7mm 27dBi active patch antennas as I think many of you have. Well... I just bought the last one. Tom suggested one of the other many types they carry for a substitute. They are on the way and I will report back what I find after testing them. Tom said that they will order more of the 27dBi antennas if enough people want them. Apparently the minimum order for them from their supplier is 3000. Obviously they don't want to order that many and then sit on them. So... you can chime in here if you need/want them to order more. Either they will read your response or I will call them with the response.

Also... Tom said he was reading one of my prior posts about the expense of their MMCX lead cables. He pointed out that they are a little more expensive than just buying the parts and trying to do it yourself... But each and every cable/antenna combination is tested before they ship it out. I did not know this. I knew they took their time and put out a quality product but I didn't know they tested every order for signal. For the DIYer installing GPS into their CF-28/29 using the Sarantel... This is the way to go as it takes all the guesswork out of "If the job was done correctly"... If you have issues... You know it has nothing to do with the antenna!

I mentioned to someone before (maybe in a post or PM to someone) that they we thinking of possibly hosting a forum on their site to answer questions about their lines of GPS antennas. I think that idea is on hold for now as they stay pretty much swamped. However... Tom said they are thinking of joining this forum as a retailer. I told him I thought it would be a great idea as they could then answer some very basic questions that a lot of people have about adding GPS to their Toughbooks. (Or just about anything else!)

Also... As a reminder... They do ship worldwide...

So.... Put in your two cents.... Let them know what you think!

Rick

 

Thanks Rick, I was going to ask you this very question. I am interested in the type of active patch antenna that you have been using.

 

I think a min of 3000 antennas is not going to happen
They have a large selection of GPS antennas; It would be helpful to find out what’s in stock and available
The smaller ones might work on the cf-18/19 and the normal sizes on the stock cf18/19 bump out and on the cf-29
Then the next step is testing
We don't usually link or promote commercial businesses, but in this case it gives you an idea of all the different gps models available

Here is the link to their hard to find website

Alex

 

So just a few people interested in this huh? I'll remember that when the questions start coming out...

By the way... I tried the smaller GPS antenna... It works... But about as well or maybe even a little bit worse than the stock GPS antenna... 4-5 satellites max and it takes 4-5 times as long to get a lock. In other words... Failure in my book. I'll pass on this one... Too bad I just ordered 5 from them... Hopefully they take returns.

I'll cal them today and let them know that I must have the original antenna that I was ordering...

 

Ruh Roh,
The 27dBi (15mm X 15mm X 7mm) active patch antenna I was able to get has performed outstanding. At the time I could not afford to buy more....minimum order of 3k lot units is a truck load even for a wholesaler. boy howdy wish I could get a couple more now 0.o

Well I will keep my eye on this thread to see if the status changes and Jim D Gray gets more of the 27dBi 15mmX15mmX7mm active patch antennas in again. Thanks again Toughbook for the heads up.

 

Thanks Rick for trying out the other antenna, I guess it is the saraentel antenna installation for me. I will order it this week.

Keven

 

Keven try to get the smaller/newer SL1206 series
We have been waiting for the slightly smaller Sarantels for over a year now
And they are showing stock available on them now

Alex

 

I talked with Tom again today... He actually called me concerned that I/we get exactly what we need. He asked me a lot of questions about the mounting of the antenna... How it was enclosed... How close was it to the palmrest top, etc...

I shipped him a mock-up of how I do it. He said that he would try to tune the next batch of GPS antennas to be enclosed in the plastic WM Cover that covers the sled entrance.

They are also getting into all sorts of cool things. Need a GPS antenna embedded into a piece of plastic? They can do it! I was thinking back when the Sarantel was mounted to the top of the LCD... The downfall was the weakness of the mount. BUT... If it were cast INTO a cornerpiece... It would be bullet-proof! Another BUT.... You would need to order in quantity to reduce the costs... Teo... If this interests you... We could possibly look to make a bumpout opposite the WWAN antenna. With a high yield active patch antenna... Or one of their new Geo-helix designs.... Nothing else on the planet could possibly compare as it would be built to our needs.

Jim D Gray ROCKS!

 

Now if only Panny would talk to Jim D Gray and TB... well then I wouldn't have to read GPS mods, now would I

 

Thanks Alex I will.

 

+5!!!!

I can't order 3000 but perhaps 5? I know at least one for me and a few others who are interested!

If I find the money tree, I promise I will order 3000.

 

I called them today to order the new 1206 model antenna, but the gentleman I spoke with advised me that they were not in stock so I ordered the standard geohex sarentel antenna that everyone has been using.

 

They have a newer model that they have been hawking... It is a much stronger antenna in general so they say with signal at least as good as the Sarantel S... They sent me a sample to evaluate but I haven't had time to do it yet...

 

Can someone enlightem me to who Jin Gray is? I have got to start feeding my brain about this GPS stuff you guys are doing. I am totally lost!

 

Toyo

Jin might be one of Jim Greys family members
I don’t know Jin, but Jim sells the Sarantel and other GPS antenna’s we like to use in our projects

Alex

 

Actually, Jin is spelled Djinn. Its one of Teo's aliases. Just rub the lamp!
CAP

 

Alright smartass! I was sorta busy as I was typing that. Kinda like pushin the innards out. Yea, I said it.

What is the difference between his and Panny's antenna? Better performance, cheaper, all of the above?

 

Selection is the main reason, he has quite a few different styles and sizes

The active sarantel has a wider view of the Sats ,so it receives more of them
Some of the active patch type that he sells would probably be equivalent to the newest cf30 type of antenna ,but his would be cheaper than the panasonic
I believe that the older type panasonic stock antenna's would not be any good as they are usually replaced for the newest models

As I see it there is three main factors in having a reliable Gps fix

The gps engine module used

Antenna

Placement of the antenna


Alex

 

Well, it figures...a day late and a dollar short! The Jim Grey website is gone and I am now ready to order a GPS antenna... is he going to be back? Is there another supplier? I was considering buying the Sarantel Geohelix-S Active GPS Antenna and mounting it at the top left hand side of the screen.

 

They are still there just logged onto my account, try this link http://www.jdgastore.com/index.php?

 

A word about the 12mmX12mm active patch Tom sent me as a replacement until the new ones get here... I was skeptical after trying the 10mmX10mm passive antenna. I could get 4 sats max. I talked with Tom about this and after I sent him a quickly hobbled together mock-up of how it is installed... He suggested that I insulate the very top of the antenna to make sure it doesn't ground against anything. Well... I used a little square of Kapton tape on the 12X12 ad VOILA.... A very nice signal. I haven't had a chance to experiment yet... But it seems the signal is just slightly less... But you do acquire more satellites. It was driving rain and very windy when I tried this and then another brief test when it abated for a few minutes. But hopefully I will have the time tomorrow afternoon to play around with the setup a little more.

Tom said that since they are working that good that he might no have his supplier tune the next batch of antennas to out use... I asked him to delay that until I tested a little bit more. An antenna tuned to exactly our needs would be perfect! I told him I would call him Monday or Tuesday with my findings.

I really hope that they either join here as a member or start their own forum over there.... It would help out everyone.

 

Weeeeeeeeeeellllllllllll....... I called Tom to crow about the 12X12 a little prematurely... Either that or, at the very least, I need to play around with it a little more.

My Brother-In-Law was up this weekend. We were all dorking around with our IPhones My Sister-in-law has the original 2G... My Bro-in-law has the 3G and I just bought the new 3GS (VERY cool by the way!) We were checking out the GPS on the IPhone... Mine shows me squarely on whatever corner of my deck I happen to be on when I am in Satellite view. We were amazed.... I was telling him a bout a special build... A 1.6GHz for a guys offshore sailboat... I whipped out the CF-29.... NADA... No signal. AHHHHHHHHH

I just got off the phone with Tom and we're both baffled how the same exact installation could vary so greatly... The only thing I did was a battery recalibration on it. The gold cap should have retained the settings so that can't be it.... I was baffled. I had one last 15mmX15mm 27dBi antenna....

I asked Tom to scrap the tuning of the antennas if it was going to cause a significant delay in their manufacture of them. It's going to take a few weeks.

One thing though... For any enterprising young lad.... He has offered to build an antenna into a CF-29 LCD corner if we want... Not sure how much a run would cost... But it may be worth it. Just a thought...

 

I know this thread is for internal GPS but this might apply. Has anyone opened up a BU-353 to see what's inside for an antenna? I assume the GPS engine must be very similar to the EM-408. I got another chance to compare the CF-30 to a very big dollar surveying instrument today. The surveyor said that he was working with accuracy of .01 foot or better, so we wrote down the exact location he was showing on a 2" monument set in concrete. I put the BU-353 on the monument when he moved.
Big Dollar Machine: 40deg 19min 20.182sec 70deg 59min 15.090sec
CF-30 with BU353: 40deg 19min 20.148sec 70deg 59min 15.090sec
This is stunning accuracy for a GPS which costs 0.00111 as much as the big dollar unit.
For the linear challenged, the Latitude is off by 3.94', the Longitude is "dead nuts".
CAP

 

the thing is, is the bu353 constantly accurate? because i know the big dollar machine would be extremely reliable...

 

Capt.... We aren't talking about internal antennas ONLY (GPS engines though)

As I stated... Tom said they would be willing to custom mold parts for us... ALA the Sarantel derivative atop the CF-29 Lcd.... Or a custom molder bumpout on the CF-18/19... Whatever we want. I am not sure what the run amounts would need to be or if it would be cost effective.... It sure would be damn cool though!

 

Actually they are very consistent. I just post this because it was the most recent chance I had to actually "get the facts", if you will, as opposed to a lot of codswallop from people selling GPS. I know there can't be a lot of difference between the EM-408 and whatever Sirff III engine is in the BU-353. The 353 is very not fussy about orientation, I know that it is not troubled by being mounted on its side like the antennas in the CF-18 and 19. Therefore, it probably would not have a problem with being mounted flat in the corner protector of a CF-29 or 30. Just thinking, whatever is up with the BU-353, its all the GPS you are ever going to need, so if the antenna setup inside the puck is small enough to fit into a Toughbook corner protector it might be worth it to look into trying a matching antenna with an internal setup. I am well aware of all the caveats about omni directional antennas and only half a view of the sky etc. I don't know why the 353 is so immune to orientation, it just is.
CAP

 

oh ok thats good. i wasnt sure, hence my asking.

 

To answer Cap..question. The antena embedded on BU353 is as the same as the patch antena on em408 and other gps module with a size of 25mmx25mm if I am not mistaken. It is attached to metal frame that encased the pcb and stand as ground plane of the antena itself.


ohlip

 

Teo... Yes... You are correct on the EM408... The back to which it is attached is the groundplane... Which is also why they give you an MMCX connector.

I'm all for trying new GPS suggestions... But I've had bad experience with the delicacy of the Holux unit. The first time I went to unplug the MMCX connector from the GPS engine... The brass collar broke off on the engine... Not good. I think I may look to beefier units than the Holux.

 

OK then, I think I'm going to whack up a BU-353 and try to put the antenna in the factory bump out and the engine inside my aussie CF-18. The factory gps in my MK4 is a piece of crap.
CAP

 

Cap..there is no problem with the antena on cf-18, the crap there is the gps engine module. I used the holux module couple with oem antena and bam..I fixed 3-5 sat. right away the first time I power it up and the next is a history.


ohlip

 

Thanks Teo, I'm going to start messing with the aussie one, it has a sub-board with a useless CDMA modem on it so I guess I'll get the soldering iron out. Its starting to get cold outside!
CAP

 

I think the CF-18 OEM GPS is not getting a fair rap. I have been using both versions ie, the one with the Matsua CN-GX0290A and the newer Sony GXB5005 with the standard side mount antenna and I do not have any performance complaints. I can regularly get 3 to 4 sats indoors and can usually get a fix in less than a couple of minutes after hitting the HW 'cold start' in WinFast. This is as good as what I can get with the MS Streets & Trips module. Both OEM modules are 12 channels and I have not had the chance to compare with 20 channel units which I am sure would perform better but for non-critical GPS use I really don't think the OEM GPS is all that bad and is definitely not cr** in my estimation.

 

Waterproof... You make a good point. The GPS engine you mention is a good one. Heck I sell them in my CF-29 OEM GPS units. The issue for some is not so much how many sats can you acquire... It is the length of time it takes to get the signal... And also will it hold the signal once acquired. This is where the OEM leaves a little to be desired.

There was a thread not too long ago that discussed this issue ad nauseam. MY point is.... (And MY personal belief for MY installations only) is that if you are only using the OEM GPS for street navigation and non-critical applications.... That is fine. However... If my life depends on it... I want one of my modded 20 channel setups as they acquire quickly, hold forever and, to date, have never let me or any of my customers down.

The CF-18 is sort of a different critter though. They use a patch antenna that is geared to be horizontal yet they mount it vertically. The ground plane they use is, however, good enough to get a fair shot at the sky. I have told my customers who have bought CF-18s with OEM GPS that it sometimes is easier to get a signal if they first tilt the CF-18 on its side. Then once locked.... You are ready to go.

 

It looks like Jim Gray has the active patch antennas back in stock according to their webstore they have about 40 in stock.

http://www.jdgastore.com/index.php?act=viewProd&productId=330