is that anything like Rip Van Wickle?
I was hoping for more of a blow-by-blow
It might be hard to find a net terminal at a nudie-bar. :)
I hope if your at a nudie bar, that your NOT thinking about computers
if I under cut something, buy, oh say 0.002"... can I knarwl (sp) it, to bump up it's size? it's a bearing seat.
les would know! :)
well... right now, I could make a spacer to extend the neck, so that there is a spot where it's 0.5005", where Ican press fit the bearings.
so I am still alive.
under or over cut ?
A-L-P-H-A: You mean knurl?
just remember... measure once, cut twice
then scrap and repeat
the bearing seat is like 0.499" :/ but if I move up 1.25" on the spindle, it's 0.5005" ~ 0.501"
something willy loose when being machined?
A-L-P-H-A: Freeze the bushing and measure it.
Heat the bit you're making the seat from to machine it as well The htermal creep should help.
I just pressed a spacer and two bearings onto the thing.
it's not going to come out... or atleast it'll be a giant pain in the ass to get it out.
had to put like 160 lbs of force to press the bearings on.
A-L-P-H-A 160 lbs? you sure your not missing a zero.... 1600 lbs?!
I'm 160lbs... I had to use a 1.5ton arbor... well... my 160 lbs on the level on the 1.5ton arbor.
so, yeah, definately more than 160 lbs.
A-L-P-H-A: 120F-150F metal means the part will shrink slightly when cool.. Real handy for doing bearing seats.
Phydbleep. I just pressed them on. The issue was that the beating seats were [the original position] was supposed to be 0.501" or 12.71mm.
but I ended up going under... 0.499". but the part higher up the neck of the spindle, was 0.5005-0.501"... so I just made a spacer, and pressed everything on together.
I now just have an extended neck for milling.:)
19k rpm bearings. or where these 23K rpm?
* Phydbleep needs some 100k units.
I'll probably end up with needle races for that.. :\
whats that site with the 60K rpm router video
dyna motion or something
you find it?
60,000 RPM spindle on this router video http://www.datrondynamics.com/
OMG, I need one of those.
A-L-P-H-A only $46,800 USD
$4.5x my cavalier. $2.25x my grand AM gt.
only 99% more to go
man! everything good is "OPTIONS"
I should be able to finish my spindle tomorrow.
cool, give it to me!
why? it's rated for like 20K rpm [well the bearings are]
A-L-P-H-A: When you're done with that I need a X/Y table. :)
I would like to find one of those motors they are using.
A-L-P-H-A: I had a thought about bearings.. Turbo-charger bearings for a diesel truck.
Phydbleep, reallly how fast do you really need a spindle to go?
Can either of you figure out what rails or bearings are being used here --> http://volleyzoo.com/monster/images/Dscn0207.jpg
it looks like skatebearings, but I can't make out the rails
* Phydbleep goes 10X for abused bearings.. 100K bearings will get run at 10k an last almost foreever.
Oh boy! Spindle motor by Harbor Freight.. :)
the rails are round stock..
If you look at the right edge of the spindle mount you can see the edge of the bearings.
the bearing in the router will die in 2 hours.
Come on guys... focus! bearings and rails. Phydbleep that's not JSUT round stock
Standard 3 bearing "Y", not 120 degree though.
Sealed bearings.. That's about all i see
What am I supposed to be looking for?
that rail looks like this --> o-
that bearing design sucks arse.
look at the left edge
Jymmm, it's aweful.
give me two weeks, and i'll sell one on ebay. with a better design.
A-L-P-H-A FOCUS on the rails
what are they
looks like a 1/2 rod attached to a 3/8 square bar fro a space.
drillrod mounted to flat stock.
Yeah, What he said. :)
that doesn't seem right though.... an aweful lot of work mounting that.
That's what it looks like, but do they even sell something like that?
Jymmm, nope. it's called a mill + drill + tap.
too bad =)
I'd probably go with round oil bushings.
bronze oil impreg bushings.
5/8" or maybe even 3/4" Nice heavy stuff.
on some PGS round stock.
with a bracket mounded for two units. locked down.
be so easy to make.
A-L-P-H-A did you check out those steppers I found?
1" drill rod, drill 3/4" deep and tap 1/2" NF every 4 inches..
5/8"ID x 3/4OD" x 3/4"lenght Plain Sleeve Bearing = $0.57/each
1" drill rod = expensive.
Phydbleep not enough clearnace
I nevre said it was cheap.. I was just thinking sturdy. :)
@ 120 degrees
Phydbleep, it's a freak'n HF router!
think of how sturdy it really needs to be.
You should see what's left of my cheap die grinder. :)
1 collet and a bit of shaft..
6ft of 1" drillrod $45.58
The motor in the stick-blender I got for the wife is almost as big as the one that was in the grinder.
Neither one was really designed to last. :\
A-L-P-H-A where you find 6' drillrod for $46?
US$ or CDN?
you sure 6' and not 3' ?
check out www.onlinemetals.com and call them to see if they have it in O1... it's pretty cheap there too.
mcmaster, part # 8890K576
I found 12' for 78.48
Jymmm, link would be good you know.
A-L-P-H-A: See there.. You scared him off. :)
nevyn_ is now known as nevyn
SWPadnos is now known as SWP_Fest
SWP_Fest is now known as SWPadnos
* alex_joni greets the fest_people
alex_joni (suck up)
Jymmm: don't make me tell you :D
alex_joni Go ahead punk, make my day! =)
does redpoint work for you guys?
paul_c : WTH? nist.gov
Jymmm: fest is at NIST's facilities
ping rayh & Co...
not a chance...
heh.. JMK doesn't resolve
he's just an unknown IP number
in a big pool of anonymous numbers
paul_c: how's the FEST going?
paul_c : grab me a spare cesium clock, will ya?!
yup - and I have the paperwork to prove it !
[13:03:49] <alex_joni> http://www.tion.ro/pubs/Bildserie/inundatie2/Bildseite22.shtml
So, is anything actually going on at fest, or just a bunch of semi-socialization?
much discussion (technical and architectural)
hopefully serious hands on work will get started today
jmkasunich not being a smartass, but what are you considering "hands on" over there?
* alex_joni is showing his hands
* Jymmm hands alex_joni gojo
orange hand cleaner
orange and pumice hand cleaner
jmkasunich ah, ok.
jmkasunich If they start with "Hello World!" demand a refund
alex_joni and they lie, use it with water =)
good morning fest!
rayh is who I had a question for
you just missed him
maybe somebody else can help?
I dont think so.
he may have made the disc I have a question about
tonyp: what's the problem? maybe I can help
looking to get my limits working
hmm.. think I read some mails about that?
4.2 was suggested but I need to know if the code was altered to work for one switch per axis
right..so: what's still bothering you?
one switch for limits & homing?
I was told rayh may have altered the code to make it work and dont want to dump everything just to find out it doesnt work
yes one switch
tonyp: got a few minutes?
ehh.. here he is
rayh: tonyp was eager to ask you smthg
rayh is now known as rayh_fest
he's hiding from me
rayh: <tonyp> I was told rayh may have altered the code to make it work and dont want to dump everything just to find out it doesnt work
Hi guys. Tony.
don't think so
bugging you again
did you alter the code to make the sm limits work or do they work straight out of the box
No problem. We just made some choices and I've got a bit of time.
They are a part of both mini and bpt definitions.
Are you not able to use them.
ok, paul_c said you may have changed something and I didn't want to redo my computer until I was sure
It was just using one of the limit switches to home off..
So you still need two switches.
Yea. We've got some sort of cannel problem.
not to mention spelling
spelling can be fixed
No there were not supposed to be any changes to limits and homes.
so I still can use one switch for limit and home
The SM version did a small change to ease homing but I don't believe it is still in there.
You should be able to.
the change if I remember was to look for the index pulse rather than the switch?
hi fest guys
Im not at fest though
would just be in the way
still working on limit with the motenc?
or is it stepper
tonyp: Probably the neg limit is the pin to use.
tonyp: any issues on trying emc2?
going to do that when I get off line
have a copy ready to go
martin is now known as Imperator_
Rayh, I thought you said yesterday to tie all three together
Fest is considering a move to consolidate future dev to EMC2
well seems reasonable
I did but paul reminded me that the neg limit is handled in a different way for homing.
so where do I solder the 5v input wire. Please be specific
The EMC2 thought is to make it capable for steppers and servos and set up some standard scripts to produce a bpt or mini personality.
tonyp: This wire is the return from your prox?
alex_joni: are you arround ???
any fundamental problem with transfering SQ to emc2?
Pin 13 is the minus limit.
les: don't think so
Sq is only three axis
Thank you, I will put the wire there and hop I don't blow things up.
We talked about SQ and the three axis limit.
is a SQ capable of 6 axis imaginable?
The prox is running on 5 volt?
no, kicking a relay to send the 5v
with a resister to make sure
tonyp: put some limiting diodes to be sure
so sq->emc2 is a no I guess
alex_joni: My imagination is rather limited in trajectory planning.
I'm just a lowly toolmaker, Im not good at this stuf
* alex_joni joins rayh_fest's limit of imagination on TP
les: might work on 3 axis... but that's not a solution IMO
No problem tony. If all else fails, I'll be back by during the second week of next month.
Im going to work to dump the computer. thanks alot. will let you know
les: There is support for the capabilities of SQ
have fun in DC guys. Dont just work, play a little!
It may take a bit but your Traj issues are right up there on the list.
well i'm all eyes.
alex_joni: sorry that we disappeared yesturday, but they shut down internet connection at 5 p.m.
IMO top priority is to migrate the capabilies currently available with EMC
to the EMC2 branch asap.
Had a short discussion with Till about something simpler to replace tp and tc
ah...emc-list just came alive again
He would like to do that
so what is SQ?
Imperator_: no sweat
did anyone see my comments to till on the dev list?
about the purpose of cubic.c?
wanted to know if I was correct
i.e if emc has a cubic sub interpolator why is it so jerky?
les...how high (in order) can you go and still have enough computational power?...does that really do any good?
dave prob quintic these days
no need to go further
anyone tried it?
quintic is the lowest order that can be symetrical and jerk free
I'll have to take your word for it
quintic is common in controls, but of course not with emc.
a lot of floating point math has to be done....
not in real time
well that helps
you can precompute?
no TP really has to be hard RT
yes dave...a tp just changes one list of motion commands to another
quintic requires min 6 pt lookahead
and does some smoothing in the process?
* alex_joni goes away for a while
a short while
A tp's queue could even be stored in a file.
but it might be HUGE
so how much of the tp needs to change to do this?
there are some issues with non causal stuff like feed or in the middle of a run etc
nothing is ever simple
the emc tp is done in RT
which is a bit computationally intensive
but doesn't have to be?
no it does not
does it get any easier if one goes non-rt
no having it all rt is prob simpler to write I imagine
ray you still around?
I have studied TP math a bunch....pity I can't code in rt linux heh
Oh...I think you could do that...
they have prob vanished to get some work done
C is just a step by step process
I have only written dos based c programs
but only one level above machine code. <grin>
not much different, just a lot longer
yeah I think the longest I have done in c is a couple thousand lines or something
I cut off at about 1K and that was all simple chemical calcs
but then divide and conquer is the only way to write long programs anyway
c I can do...I just don't know the ins and outs of a RT linux based os
I'm sure you could get help with that
so what are you waiting for?
paul to get here
that might do it
well I want to beat the hell out of sq....
of course if Till's student will do this.....
gotta go get my walk in for today....and then convert more steel into chips
I have some decisions to make about commercialising emc as a control on a product
catch you later.
so what is happening in em-fest land?
they were here earlier but vanished to do some work I guess
* alex_joni is laughing his butt off
[15:18:37] <alex_joni> http://darwinawards.com/
pretty quiet around here
les: still around?
les: from http://www.linuxcnc.org/handbook/part3/sourcefiles.html
I think what you said in that mails is pretty ok
* alex_joni found a good paper to read: http://batman.mech.ubc.ca/~ial/publication/theses/sonja.pdf
les...I had to google sonja.pdf to get the paper for some reason I could not get alex_joni's link to work although it looks the same
rayh_fest WooHoo! Where's are "All we got was this lousy tshirt"?
Acme threaded rod.. 1/2-2 ?!
* Jymmm is anyone
* Jymmm waves to alex_joni
* alex_joni waves back
alex_joni have you ever heard of acme threaded rod 1/2"-2 ?
I'm not good with ''
diameter doesn't matter... 2 TPI
machining is not my field
Jymmm: My old SouthBend has 2TPI as a standard threading pitch...
Jymmm: You'll only get it in right-hand though.
$10/ft steel, $17/ft stainless steel.
Cheese it! He's from a .gov. :)
they all are
Fido: FEST is beeing held at NIST.gov right now
As long as they don't classify emc as a "national security" precaution, Let them party where they want. :)
how's it going?
A bit hotright now.
hot is good
But I think that we are getting past the issue.
* paul_c & rayh have the nomex to hand ;)
We are trying to join bdi4.xx and emc2 head.
what's a nomex?
rayh: that sounds great
* alex_joni wonders what the outcome will be
the outcome will probably be that I can no longer build it on rtlinux/2.4
We have agreed that we will produce one code base.
alex_joni: nomex is a fire resistant material..
cradek: get a 2.0.129 machine
We are expecting to support 2.4 and 2.6
2.4 support will not be dropped if I have anything to do with it.
* alex_joni joins the oh good
* paul_c still uses 2.4.xx for some things....
cradek: the issue is kbuild... support for non kbuild systems may get dropped eventually
2.4.27+ has kbuild
the only thing I know about kbuild is that I don't have it
cradek: but you might add it easily
but rtlinux won't work with a newer kernel.
at least I think so
rtlinux works on 2.4
* paul_c slaps alex_joni with a wet kipper ;}
* alex_joni enjoys it
* alex_joni pulls the plug from paul_c's network connection
it has patches for up to 2.4.20
(which is the one I use)
Phydbleep I saw that on msc, but never heard of such thing. Seems too tight
Jymmm: It neds up looking like a twisted piece of flat-stock. :)
Phydbleep ah, ok. dont seem reliable
YOu guys GOTTA watch the travel channel right now!
* Phydbleep prefers his food not to protest or fight back too much..
hmm.. stick a fork in it
till it stops protesting
alex_joni : The beating frogs heart wasn't fighting back.
Anything I eat has to be non-moving or at least consenting. :)
there goes the net @ NIST
Speaking of frogs.. Did you see that there's still frogs exploding in Germany?
so, any news from the festering masses?
or is that festing?
no, wait, lets stick with festering.
They're still passing laws?
good it's not fisting ;)
well I saw this film once ...
but, lets leave that
* anonimasu hides
don't do the quacky goat thing again
was enough for this year
yeah, its pretty bad.
maybe even worse than tubgirl ...
* alex_joni still wonders if the tubgirl wanted to do that...
* Phydbleep can do a decent impersonation of an elephant or a plum tree... :)
saw a *nice* mill today
very neat little VMC
* anonimasu nods
I cant remember...
just that it's too much..
the guy had just spent 4K on tooling and 3k on a vice
Mmmmmmmm Bat Soup!
10 tool changer ...
1) Catch your Bat 2) Give to Chef to cook for you
not in the UK you dont
robin_sz: You should spent that money on tools instead of pandering to your baser instincts. :)
lasering is looking gooooood
my bad... Stir Fried Bat
got a nice new dell today
2.8 P4, 17" monitor, etc ...
whats that? 380 USD?
Not tooo shabby. :)
just an office desktop
I was tempted to plug a colleague into the mains for an hour because of his "you cant run business applications on a celeron" rant ..
what an arsewit.
robin: did you have some outage today?
dont think so ..
robin_sz: Do it at his house where it goes on his meter?
didn't work at noon
[robin@quacky robin]$ uptime
10:48pm up 37 days, 16:49, 1 user, load average: 2.71, 2.22, 1.97
maybe link loss?
redpoint.co.uk didn't work
15:57:22 up 44 days, 23:06, 5 users, load average: 0.09, 0.06, 0.01 :þ
and quacky too
yes, but where did the link fail,
you tracerouted it?
didn't have time to investigate
robin_sz: Give me an IP and I can try to traceroute it from here
I get an SMS if another box in telehouse london cant see quacky
main:~ # uptime
12:45am up 54 days, 12:08, 1 user, load average: 0.00, 0.00, 0.00
Phydbleep: well, its working now ...
alex_joni: I got quacky up to over a year, before a >1hour power outage sank the ups a few weeks ago
main:~ # uname -a
Linux main 2.2.13 #1 Mon Nov 8 15:51:29 CET 1999 i686 unknown
my best yets is 3 years odd
mine is about 1 year
because of tight HW budget
can't expand in advance as much as I'd want to
hot plug scsi helps
yeah... that's expensive :P
* Phydbleep is still running all <1.7 Ghz machines.
it is here
you just use standard scsi and chicken blood
standard scsi hotplugs fine if you are brave
proxy:~ # cat /proc/cpuinfo
processor : 0
vendor_id : GenuineIntel
cpu family : 5
model : 2
model name : Pentium 75 - 200
robin_sz: That's a "rubber chicken" not "chicken blood".. :)
stepping : 12
cpu MHz : 132.956
fdiv_bug : no
hlt_bug : no
f00f_bug : yes
coma_bug : no
how about this crappy machine? ;)
alex_joni: Sorry, I thought you were bemoaning the sad state of your router. :)
it runs perfectly ;)
was a bit tough to install
9:44AM up 140 days, 6:28, 3 users, load averages: 0.23, 0.14, 0.09
vendor_id : AuthenticAMD
cpu family : 6
model : 2
model name : AMD Athlon(tm) Processor
stepping : 2
cpu MHz : 956.918
cache size : 512 KB
That's my router/firewall
cpu family: 15
model name: Intel(R) Xeon(TM) CPU 2.80GHz
cpu MHz: 2793.076
cache size: 1024 KB
robin_sz: yeah, But that's not your router. :)
* Jymmm hands robin_sz some durian fruit!
Or if It is I'll trade you it for my desktop machine. :)
true ... but if you were truly observant .. you'd notice the "processor : 3"
one Xeon is never enough ;)
robin_sz: I did.. That's why I offered to trade. :)
robin_sz come on, only three?
Jymmm: if you look at the opther osts, you'll see they all start at 0
robin_sz I'm just razzing ya =)
*sure* you are ... ;)
* alex_joni goes to bed
G'night alex_joni :)
fscking bill gates is actually getting half decent at some of this software
[01:02] * alex_joni goes to bed
I'll regret this in the morning... :(
* Phydbleep throws the TV on Cartoon Network where the kid can watch Megas..
I usually stay up til gon 2am
yeah.. but do you go to work @ 0800?
I have children
* Phydbleep has a 3-1/2 year old daughter that want to be a motorhead..
anyway .. new PC, first remove AOL, and a zillion other pre-installed internet connections and crud
This is going to be scary in a couple of years.
"Home of the FREE 72 oz Steak"
install firefox, thunderbird open office
Phydbleep Just wait till she's 13yo
robin_sz: Lite-Step and XP-Lite to cure most of windows?
now ... windows networking used to be more "windows notworking"
but its pretty good, it discovered the shared printer on my wifes machine (which it found all on its own)
and the FAX modem as a fax printer was found and configured in a snap
robin_sz : Heh, I'm actually gettign ready to install NetBios
robin_sz: XP-Lite.. Lets you rip out .. Outlook, IE, Messenger, bunch of other useless bloated crap.
* Phydbleep has 4 of 83 components installed for XP.
but I dont know jack shjt about windows
I'd probabyl rip out the useful stuff
robin_sz not much of that
robin_sz: He is right you know. :)
I have to say, XP is actually OK
robin_sz I reverted back to 2k from XP on one muachine so far
never seen 2k
I saw 95
robin_sz: Run XP-Lite, install Lite-Step, and slap on Cygwin for a nice finshed X layer. :)_
then just left well alone until XP arrived
oh, id never install cygwin
robin_sz XP has bells and whistles, but also has a *LOT* of unnecassary bullshit too.
cygwin make no sense to me
robin_sz remote desktop is enabled by default, so is many other thigns as well.
Hehehe.. I saw what a mess the WFW stuff was and went from DOS6.22 to linux. :)
when I want a posix shell ... I use linux
Phydbleep WFW was easy
it didnt even work
I have to keep at least 1 partially windows box around for compatibility...
Hell, I still have dos network floppies I use
boot from the fdd and you have network sharing
or a file share, either one.
I have linux
why would I want DOS?
linux for fun
and web stuff
XP for desktop cad /cam
robin_sz It's not for everyone, but it works for me. Especially for S&R type stuff.
Hehehe... I have tftp enabled here for diskless systems.. Slap a boot floppy in anything with x86 and boot linux .:)
robin_sz Search and Rescue
you keep losing your PC?
robin_sz No, during use in natural disasters
oh, like GW winning an election?
yeah, like that
we call it "RAYNET"
Jymmm: Volunteer fire dept.
Phydbleep Ham Operator... RACES and ARES
Phydbleep: no, it radio enthusiasts who set up control and comms stations in the event of a major disaster
Phydbleep: they havent figured out that cellphoens have been invented yet
hm, if a disaster happens cellphones wont work..
robin_sz what anonimasu said
the nets cant support nearly enough traffic at once..
Even the 911 Dispatch center uses MS-DOS
remember the nets give priority to emergency services traffic
robin_sz it's VERY true.
robin_sz: but thoose arent the only ones helping out in a disaster..
so they will drop normal users
anonimasu: they are
robin_sz Cellphones and Trunking radio systems go down during most disasters.
robin_sz: you are wrong they do go down..
robin_sz: maybe not if you have 15 masts closely..
they are all land-line based communications - and completely unreliable
not land line
not in the UK anyway
robin_sz cellphones are landline
dishes at 37G mainly
cell phone sites
they arent landline over here..
although they cant support enough traffic anyways..
robin_sz and no emergency power to them either.
hm, they have a week of power here..
anonimasu assuming NORMAL traffic
I went into one of the cellhone masts with a tech to have a look a while back..
and the police/fire/ambulance etc have their own VHF comms anyway
And are pre-empted for "Official Use Only" in the event of a disaster..
Cell-phones that is.
* robin_sz nods
well ever tried calling somone at new years eve..
* Phydbleep is thankful for the hams.
or somone at a large convention..
assuming the police/fire can even get to you to offer help or even know you are in need of help.
everyone calls their relatives to check if they are ok..
* anonimasu sighs
all I've ever seen them do is provide essential comms fromt he start/mid/end of marathons and other races
I avoid my relatives like the plague.. In fact given the choice I'd rather have the plague. .:)
with DOS APRS you can easily handle traffic of 9000/msg per hour
AX25 packet racket?
that works real well
right up until the point where more than 3 people are on the same channel
robin_sz you may know machining, but you know beans on comms
robin_sz This is one of my radios http://www.universal-radio.com/catalog/fm_txvrs/4116.html
its a radio
most of mine a are older
That's "An expensive radio." to you. :)
robin_sz notice the serial port? (one of many)
robin_sz and the one next to it for your GPS
robin_sz it's not JSUT a radio.
either way, when the channel is full, AX25 fails
Nope..It's a billboard advertising your position to all and sundry. :)
thats what basically killed AX25 in the UK
people just piled on more watts ...
heh stupid users..
or maybe it's the protocol that's stupid..
you should bear in mind I ran one of the first 9600 baud links on 1296mhz in the uk
that was back in the days of the TAPR tiny2 AX25 controllers
that was fun to start with ... build it yourself froma z80 and bits :)
well night guys
I must dig out my radio gear again ... theres a 10ghz SSB rig I never really got any use out of.
ah well ... back to sorting out the new PC
* Phydbleep is waiting for people to figure out that 2 Wi-Fi card with external directional antennas will make a nice LOS link.
I think thats been done
over silly distances too
With yagi's.. It's kinda lossy.. I want to do it with dishes. :)
yeah, .. just use yagis and some of the MIMIC amplifiers to up the power
75cm dish beats a pringles can any day.
pringles cans make good feeds, but lousy antennae
3db at best
or coffee can
75cm should be ~ 21db IIRC.
Phydbleep: you might as well just up the power, illegal of course but so are the dishes
Nope, dish is just a directional feed over here. :)
look at the licence
antennas of any kind are NOT illegal in the US per FCC Part 97
nutsacks to you
you might have local antenna ordanices
many devices are licensed on therre power output
PEP !+ Antenna
robin_sz: It's ERP (effective radiated power) that is the limit here..
I could run 50kW into the lossiest POS anntena and as long as the ERP < 100mW I'm legal. :)
Jymmm: wifi cards are limtied by internatioanal conventionetc to a certain erp
robin_sz no antenna is going to increase power
ROFL @ Jymmm
Jymmm: you call yourself an amateur radio operator?
Jymmm: go find out what ERP means
then come bacl
look it up in "radio 101"
Jymmm: Look at the "fractal antenna" and say that.
* Phydbleep is digging for the link to that one.
Phydbleep: it also means you can run 1w to a dipole or 10mw to a 20db yagi and hit the same limit
so limits are dbd
some are eirp
effective isotropic radiated power
Jymmm: if you look at some bands you'll see the limits are different .. some it the total watss, some its the watts * antennae gain .. it depends. wifi cards are part of the watts * antennae gain thing, they get a dispensation from licensing so long as they are below a certain eirp
[22:43:14] <Phydbleep> http://www.hbci.com/~wenonah/cfa/
synthesize your e and H fields ...
Have a look at that puppy. 210ft tower replaced with a 21ft stubby. :)
popular in the gulf states
(sand makes a real crap ground plane)
Yeah, It takes out less mobile homes if it falls over. :)
dunno how well they go at real powers though
* Phydbleep was born In Texas and lived in Louisianna and can make such comments with impunity. :)
biggest tx i ever worked on ... in raw watts terms ...
Not counting spark-gap xmitters. :)
that baby was driving a 700 foot T antennae
we had the thing surrounded by UV detectors
for when pigeons landed onthe insulators
The old Lincoln welder with the outboard Hi-Freq unit made a good one and would take AM.. :)
with 500kw, you have to drop carrier to extinguish a spark when a pigeon flashes over :)
wasnt the CFA doen by GM4HAT if I rememebr right?
Yell "GOOD MORNING TEXAS!" into a carbon mic and hear the whole neighborhood scream when the football game went away. :)
Haytley antennae technology?
[22:51:41] <robin_sz> http://www.antennex.com/preview/cfa/cfa.htm
Hmm.. Gotta wonder what one of those would do for the range of my WAP.
actually in the UK it would do bugger all
they are TDM in the UK
so the maximum delay between handset and base is limited
you can actually have a perfect signal and be "out of range"
you're CDM out there in the US?
Shouldn't there be a "Your Service Provider is a cheap SOB and needs to add capacity" message the phone displays in those cases?
its not a question of fullness
its a pre-programmed "no user more than X miles from a cell"
CDM might not suffer from that
ysstems here are a motley mix right now... cdm, gsm, tdms, and some voip stuff as well.
There's dropping the cdm stuff though due to the new regs for next year.
cdma and tdma are the comms layer .. the physical layer
GSM, voip etc are protocols carried by them
* Phydbleep wonders if the public will revolt the day their old tv's all stop working..
Legislated shutoff of the standard 6mHz tv system in '06... digital/hdtv only from then on.
they sold the bandwidth to phone cos then?
All new equipment has to comply with the "no-record" flag as well. :(
"welcome to the land of the free, please leave your rights outside"
Which makes it really hard to catch the govt in a lie on tv because you're not legally allowed to have the recording. :(
Jymmm seems to have gone quiet?
Probably looking at emigrating somewhere safe like Beirut.
* Phydbleep lives in New Mexico and expects the dumbasses to start a shooting war with Mexico next.
it wouldnt have been so funny if he handt just told me I knew squat about comms ;)
I wold have been gentle on him, but after that , hey .. he was fair game ;)
here you go
the full skinny on wifi and antennae gain and the FCC
[23:07:36] <robin_sz> http://www.wi-fiplanet.com/tutorials/article.php/1428941
Yep.. I can push the whole 100mW from this 802.11g card into a 75cm/21db dish and still be well under the legal limit. :)
for fixed operation?
Yeah, Point2point. :)
eirp +11dbw eirp
limit is 6dbw
18db gain ofer the stock antenna.
do you would be 5db over
\For antennas having gain greater than 6 dBi, the FCC requires you to reduce the transmitter output power if the transmitter is already at the maximum of 1 watt.
which bit of :
the FCC allows operation up to 4 watts EIRP
did you have difficulty with?
The reduction, however, is only 1 dB for every 3 dB of additional antenna gain beyond the 6 dBi mentioned above.
As a result, the FCC allows EIRP greater than 4 watts for antennas having gains higher than 6 dBi.
you are 15db over the 6dbi
so -5db down,
upi are at -10db
OK, your legal
I told you so. :)
I confess I was wrong :)
so you could run -5dbw into a 21dbi dish
+16dbi, or 40w eirp
Should be stable for ~ 8.5 miles with weather figured in.
depends on how high you go
Direct line of sight.
yeah, but the fresnel zone
quite large at 2.4ghz
you know about the fresenl zone?
imagine you eline of sight.
Air disturbance at ground level due to thermal effects?
imagine a wave that takes a path at say 2 degrees, bounces off someting, and ends up at the rx 180degrees out of phase, due to the path being 0.5 wavelengths longer
One end will be up a hill (figured it as a bowl/valley).
you get a "lens shaped" zone .. from each end of the link
thickest in the middle right?
Yeah, You're talking about ground clutter, :)
a reflective object on boundary of that zone creates a cancelling signal
for a reliabel link you need to keep the 1st and 2nd fresnel zones clear
this is why dishes go up masts, line of sight, plus the fat sausage shape ;)
( I might have spent a year calculating link budgets and path planning with the BBC ;)
Yeah, No reflective things in the path.. /me always figured it as a cylinder 12x the wavelength.
radius not dia.
[23:25:25] <robin_sz> http://www.westcon.co.za/images/fresnel.gif
[23:27:07] <robin_sz> http://www.zytrax.com/tech/wireless/fresnel.htm
Bout 8ft at 2.4gig/9miles?
[23:28:09] <robin_sz> http://www.zytrax.com/tech/wireless/calc.htm#fresnel
online calculator :)
ist fresnel zone
+4.11m of earth curvature
so two 25m towers should do it :)
35ft dia for 10miles , 20 foot towers up a mountain. :)
140 foot dia!
That's for flatland.. This is one on the flat, one on the mountain.
you need to take a map and a piece of paper and plot a path profile really
or just try it :)
* Phydbleep can look out the back door at the signal path. :)
right .. bedtime
Jymmm: you can come back now
G'night robin_sz :)