Surprising CF-28 Build & A Few Questions...

Okay... Most of you know that I am looking for a job... Since Rance Pohler never called me to come to work for Panasonic I need to do SOMETHING!

Anyway... I have a bunch of CF-28 parts... 600s and 800s... I'm about ready to list a 600Mhz that is designed to work with a Porsche diagnostic tool that I build. (Etched the boards, Solder it up, etc.) That one should hit in a few days...

But the one I am working on today gave me some surprises... All/most of my CF-28 are all parts... So to build one I have to look into the hell box and drag everything out. On this one I used a mix of 600 & 800 parts. (Screen from a 600... The rest is 800 stuff) I modded the Modem cover wth some parts that I ordered from Heartland so I could add a LAN since all I had were modem port covers. Worked like a charm... I am out of EM-408s and don't have the cash to pick any up right now... So I dug around in my hell box and found a Stock CF-28 GPS system that someone gave me over a year ago. (You'd be surprised what many VERY nice people have just sent me for free.... Or maybe I paid shipping on some of it.) Anyway I mounted the GPS and then turn my attention to a wifi setup. Well... Since I had the stock GPS in... I couldn't do what I normally do.. Which is install a paddle type antenna on the side and run an SMA bulkhead out the side.... he Stock GPS was in the way. Sooooooo... I decided to try out mnementh's RIM antenna hack. I did it right though... I modded per his very detailed instructions and then put it into the LCD cover... For some reason I decided to take out the long RIM antenna lead and substitute a WWAN antenna from a CF-29... It's shorter and less likely to bend. I'll swap in the longer RIM antenna and check the dB rating later... But I was just anxious to try it all out. I cloned the 60GB hard drive I got out of a newish CF-29 I bought about a year ago and fired it all up.

I was really blown away... The Wifi is excellent! I am using the 600mW Engenous wifi mini-pci card so maybe that has something to do with it. But then I fired up the stock CF-28 GPS. THAT is where I got my surprise. FIVE satellites ALL pegged to the top! I have never had one that worked that well.

So... What is old is new again! There is only one problem that I am having.... The CF-28/600 that I took the screen from had a tag on the handle that stated, "Screen Flickers".... At first I didn't see anything when I booted up. But then I noticed a bunch of horizontal lines at various intervals just take over and start shooting back and forth. Sometimes when it does this it makes the screen jump around also. It comes and goes. Right now it isn't doing it. it seems (And I'll have to check into this a little more) that when you thump the laptop or pick up a corner and then drop it that the scren starts doing it more. This leads me to believe that it is a faulty connection more than anything. Any ideas Toughbook crowd?

Anyway... I just wanted to post about my latest....

By the way... If you want to see what has been keeping me up at nights for the past few days... Take a look at this! The website wouldn't allow me to embed the YouTube file I have... But it is in the auction....

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=190278442130&ssPageName=STRK:MESE:IT&ih=009

 

I just "jizzed in my pants."

aka http://www.youtube.com/watch?v=4pXfHLUlZf4

 

Rick

Panasonic , and most large corporations for that matter , don’t recognize creativity

You are better off working in a smaller organization, that can benefit from your skills

I was with Sony in the 80’s and I had lots of creative energy at first but the burocracies of a large organization frustrated me

Now don’t get me wrong on this , yes the salary was good, and so were the health and dental benefits , stock options , discounts on products, and yes a great expense account

Oh! I forgot I was trying to make you feel better…..

Alex

 

Rick -

VERY well done - I've built 6 or 7 of these (though none as sophisticated as this one-they hadn't considered the issues of phosphor degradation & bias voltage modulation to prevent it - remember, these were originally intended to be replaced when they dimmed) Two of mine had green LED underlighting similar to yours, and one was built inside a blue neon speaker ring surrounding a 1" lexan panel to provide edge lighting. It made a pale blue "halo" around the covalent edges of the tubes. (Yummy). Sadly, all of my clock projects were lost in a fire 11 years ago...

Again - Well done.

mnem
*Makes two snaps in a circle for Rick*

 

Rick -

Your trial of the WWAN antenna WAS something I had mentioned in one of my other threads - as that antenna is tuned for CDMA frequencies around 1900 mhz, it's going to be VERY close to the 2400 mhz band used for WiFi. I simply didn't have one to try, and couldn't figure a good way to permanently reassemble the 900 mhz CDPD antenna I had tried trimming in my experiments.

mnem
Can the electrons come out to play?

 

Mnem.... I gave you props dude... I've been spreading your word to all. I quite a few post and PMs actually.

It works GREAT... Even with the antenn all the way down!

Bad news... All the CF-28 batteries that I have are DEAD! So I will be selling my 28s without batteries! Ahhhhhhhh!

 

Thanks dewed! I wish I could assist in the dead batt front... but I also have all dead except for the one I use.

Good luck on the Cf-28s... I know it's getting hard to sell ANYTHING in this economy; I consider myself lucky to have work at all.

mnem<~~~ Voted for... well, those who know me already know. Did YOU vote?

 

Yup.... Same guy....

 

I've been stuck selling most of my 28s without batteries too. It for sure is pretty tough to sell anything anymore everyone wants to low ball because of the "economy"

 

I'd put my 2 cents in, but all I have is a penny!

 

Interesting you say 1900 MHz since here in Australia WCDMA is based around 2100 MHz. I use Virgin broadband who actually use the Optus WCDMA network.

802.11 style wi-fi still uses 2.4 GHz, but there is a different type of wireless broadband offered by places such as Unwired who operate using a band around 3.4 Ghz I think.. Might be 2.8

Craig.

 

Well, yes - that is WCDMA, not CDMA. Different country, different standard. However, the 802.11 WiFi standard is international, so should not change.

mnem
No, thanks. I'm trying to cut down.

 

TB re: the clock,
Rick you are a man of many talents. Nice clock, unfortunately I am getting to the age where I hate clocks.
CAP

 

Hey guys.. I've had "modify the LCD-mount antenna" on my to-do list for a long time. Alternately, I've been wanting to get my hands one one of the factory LCD-mount wifi antennas so I could get some clues as to how they did it! Well guess what.. Purely by accident, I just got me a stock wifi setup!

Two things I noticed right away that surprised me. First, it's the LONG antenna, like with Sierra CF28s and all the radio modem 27s. I thought we had decided that the short RIM antenna would be closer to what wifi needs.

Second, it looks like they route it through the passthru connector at the back, just like with the radio modem cards. I guess I shouldn't be too surprised about this one, but I figured that having it wired that way would lead to signal loss and a source of noise. I was planning on just routing mine direct from the antenna to the card.

Anyway.. that's all for now.. I'll be taking this thing apart in the next few days to see if there's any other surprises!

 

Grav, how long is this antenna? Some pics please, when you're done. TIA !
Ron in SG

 

A while back, marconi, a friend of doc's in Florida and an occasional poster here was kind enough to send me the following. I post it here with his permission. Rick, note the reference to "ground plane". I asked him how he tuned his stock display mounted antennas.

"Basically I use a HP microwave network analyzer., its a kindof fancy swr meter but gives me a graph of the reflected power versus outgoing.
We have one at the TV station I work at so I might aswell use it.
I can tune while observing the graph for the best results, makes things much easier.This works well with the 2 3/4 in ant.
What I do is different attachment points than the original, mostly closer to the stem piece as possible.
On the first ant I did have to add a few chipcaps to tune it down some, no chipcoils, altho I did try the old ones that were used as a harmonic filter. nogo.
but it was passable performance wise , lucky maybe cause it was a mess. Similar to what mnementh did.
The second one worked better without adding anything, I had to remove the coax from the mount and just soldered the coax with very short leads (1/8" long each) directly at the soldertab closet to the ant stem trimmed smaller just enough to solder to.. I also had to find a good ground close to this spot as well, so I cut the flexyboard out completely and used copper foil 1 1/2" long to go from the original ground point to the ground of the coax. basically extending the ground up to the coax where it is now attached closer to the ant. It also acts as a proper groundplane at this freq..
Now we have a Half-wave ant good for about 3dB gain.
I hope all that made some sense. I was gunna post it but hadnt had the time lately as we've been busy with the digital transition,.I take care of the transmitter site too.
If you are brave enough to try it , I'd be interested how it went for you.
I have two more TB's here with ants I plan on turning over soon so I'll be doing those soon as well.

I just got in a long ant and will be trying it soon as well. Altho it'l be tougher and I will have to add series capacitance to tune out the reactance and null the standing wave at 2.4Gig.
The pattern may not be the greatest but it'l be better than nothing too.
As far as internal antennas, Ive been grabbing those flag style ones made for other laptops, and mounting then right under the batt on the screw post at the plastic side. works prettywell for A,B and G wifi.
but nothing beats the look of the external antenna tho.
You are welcome to post any of my reply if you like."
CAP

 

Grav... I have posted in a few places that I did mnementh's mod with reference to unsoldering the caps and other stuff on the RIM antenna and soldering straight from the 000 resistor straight to the base. Well... I had to replace the LCD because it was a little flaky.... Anyway... When I hooked it all back up... I still hadn't clipped on the RIM antenna lead to the passthrough. I STILL got a signal in my shop that was barely useable... All this from the u.fl lead that I had run from the wifi card to the passthrough. When I hooked up the RIM antenna to the passthrough... My signal shot up to excellent.

Now... I don't have an SWR meter... But my seat-of-the-pants meter showed that there was no difference between the longer RIM antenna and the cellular antennas that I have been taking off of the CF-29s. I know that these are tuned to cellular freqs... But still... No difference in length. I guess the signal was so strong either way... It didn't matter.

 

wanna hear another strange configuration? I got a couple 28s that have the wifi antenna embedded in the side.. where the modem/lan ports go. Unlike most though, these have the lan port and not a modem jack. Well there was still a stock modem card in there.. going nowhere! the cable was just tucked up into the corner pocket, not plugged into anything. i wonder why they would do that?

 

Was it a mod maybe? Or do you think it was from factory like that?

 

They were probably supplied to the original buyer like that as part of the specification for future use, and never actually used!

Craig.

 

There is a cable going from the modem which daisychains over to the MP serial port in the media bay. So I would have to assume that the modem is part of the cable tester circuit and is used by Telco's for testing telephone lines using the modem but they may not need the actual jack.