Hey Dan -

So great to find another senao phone user out there! 

> 
> It's amazing what 900mW (630mW in the handset) will do! ;) I'm going to


Actually - it all depends on how you decide to measure power.  Many handsets
and bases will put out 0.6 to 0.75 W on an analog (Bird) RF meter - but that
meter measures *average* power - because the xmitter is only on 50% of the 
time, their PEAK power is 2x average - so 1.2 to 1.5W peak (which is what 
matters).  For once a manufacturer who was conservative in their specs, maybe
to avoid hassles with the FCC!  (I double checked this with an HP peak RF
meter - probably up on my equipment page - yep -they peak at over 1W and if
you move a cap on the xmission line you can get 2W out of them peak, 1W 
continuous) -- obviously the first thing to go on mine was that silly warantee
void if removed sticker.

> install it in the attic and run some LMR-400 to an 8dBi omni.. no more than
> 10'.  I considered a higher gain antenna but I would rather have a wider
> beam width and settle for less gain.  I don't want to piss of ALL my
> neighbors.  I'm thinking about running the mic, speaker and page buttons
> down to a custom built panel somewhere since I use the intercom often.
> 

This sounds like a good setup.  After getting annoyed having to go up on the
roof to register new handsets, I bought some 25 conductor shielded cable to tie
in all buttons/mic/speakers on the bases)  I thought I could get by w/o it 
at first, but then more senao's showed up - I also later found innovative uses
for the page button - like alarm conditions on my microwave network - I can 
send 4 different types of alerts to my handset I carry around the house 
through some optocouplers.


> The only other thing I'd like to do is to duplex both bases on the same
> antenna... this is near impossible so I've written this off.  I may get a
> second antenna, separate them by the max distance I have available on the
> roof and take care of it that way.  I've also been looking at cheap yagis
> and making it more directional.  I'd love to get my hands on one of the 4
> liners as this would solve my problems with multiple antennas.


So would I.  IT **IS** Impossible.  Reason is that they do not run off the
same clock crystal and therefore may xmit and rec at the same time, causing
one to drive into the other (very bad indeed).    Read later on my attempts
to make them run on the same clock.  It's still impossible.

I'd avoid yagis -- true the separation goes up - but 2 omnis at opposite ends
of a house (60' or so for an average home, maybe more) would be fine.  I have
a commercial building and a residential on the same lot, so I put two bases in 
each building and got 100'+ between them - but I did tests at 50' with the high
gain antennas and they worked beautifully.  Don't forget you can also get 
separation on omnis by elevating one of them vertically by 10-20 feet or so.
And that one will be your "really long range" phone.  Vertical separation for
omnis is pretty darn good!  Yagis are going to give you a "walking east" and
a "walking west" phone (or north south) - not as versatile.  If you have more
than 50' I wouldn't sacrifice any LMR 400 loss for separation - that's why
I mounted my box right below the antenna input.

Watch out on the 4 liners - there's a subtle feature they are missing - I 
almost dumped my 900 and 920's to buy a 4-liner until I found out that it 
DOES NOT SUPPORT LINE SELECTION (you know - how we intcom 03, then talk, and
get line 3 to dial out).  The 4 liner picks FOR you any non-used line to go out.
YOU Don't get to choose!  The manual doesn't even tell you the algorythm they
use to pick a line.  

I have inbound and outbound trunks with a hunt group, so this is a no-no here.  

In on 1 and 2, out on 3 and 4 - that's how it needs to run here.  Can NOT do 
that with the 4 liner.  I don't think it even tells you what line you're on 
when you dial out.

> 
> I know this is going to piss off some hams out there.  Before you point
> fingers consider the fact that the antenna comes off and it has a RT-TNC
> connector.  I think EnGenius is Taiwanese for "FCC who?".


I'm a ham - and I have zero respect for the hams who consider themselves 
the "radio cop" - They really do give ham radio a bad name.  They have zero
authority, yet think for some reason because they have a callsign they are 
responsible for the entire spectrum from DC to light.  Sorry - pet peeve.

1 Watt is allowed in 902-928 for spread spectrum devices.  Hams never 
used 900 for more than a few applications, and no manufacturer 
ever sold 900 mhz commercial ham gear in the US.  (I think they sold some in
Japan - don't understand why it never came over here!).  The #1 rule of ham
radio is USE IT OR LOOSE IT.  They didn't use it - they have now lost it. 
Same is true in 2.4 Ghz.   I remember some ham posting on this list not to
use ch. 1 on 802.11b because their satellite is there.  He didn't have the
common sense to think that to hear that satellite, an antenna with such a 
narrow receive beamwidth would be deaf to other people's 802.11b devices 
that are not in outer space.  Just because they are "primary" there doesn't
mean he can go around telling people what channel they can and can not use.
That's the whole ham attitude that creates a bad image of hams.  They have
zero authority - leave it at that.

Come next spectrum auction, they can take 2meters and 440 and give the hams
uh - 58 GHz band instead.  That's the trend.

Since I am a ham, I am entitled to put a 13 dB gain antenna on my phone, and
should I desire, a 1500 W (yes, one point five kilowatt) amplifier.  But it
works fine as it is, so why bother!!  I'm also entitled to open up my phone
and crank the power up on it (yea - they didn't go "all the way" at the 
factory - especially on the 900s, the 920s did a little more)

The truth is the ham radio "rent-a-cops" can't do jack about it.  They can
not prove conclusively that your phone is the source of the emission.  And
even if they could, the enforcement of 902-928 is way waaaay down on the FCC's
list of things to do - below the Christmas party.  Basically unless airplanes 
can't land or police can't communicate, the FCC has a 2 letter response - the
first letter is F- and it doesn't stand for federal.

Most ham rent-a-cop-wannabes don't even have the necessary hardware to hear
let alone track and tune a spread spectrum signal like the Senao/Engenius uses.
You can spot them a mile away because they drive a beat up old van with a 
dozen antennas on it and a bunch of 1960's heathkit equipment inside.  

I drive a '95 humvee (the real one-not the H2) with a bunch of HP/Agilent T&M
gear inside.  I can see and get a general idea where a 900 MHz SS signal is 
comming from, but I can not say "it's this house" with 100% certainty.  There's
just too much junk in 900 mhz - you're watching one signal when another pops 
up that's stronger - it's either more powerful or closer.  And I sure can't 
tell you if you've cranked your phone up or not. The band is a MESS. 
It's a wonder these things work as good as they do!

This is why the military developed it years ago.  Secure and hard to find and
very reliable in noisy environments or with jamming signals.

Don't worry about pissing off the hams - open up your 9x0 and yank that rp-tnc
and either put a bnc where it was, or put a 6" tail out the hole where the 
connector was and crimp a BNC male at the end of it.  Solder it inside the box,
and you get the benefit of one less connector, and a small tail of flexible 
coax to avoid the LMR400 "tail wagging the dog" scenario.   A good amphenol 
connector and 6" of cable is less loss than their china-inc RP-TNC connector.

Before picking your attic - put a recording thermometer up there (hi/low) - I
actually built a miniature environmental box for my senao (I'll take a pic of
it open) that had peltier electric coolers and 2 power resistors inside as 
heaters - connected to a watlow 935 PID temperature controller, then sealed 
up.  The thermocouple that fed the watlow the temperature was bonded to the
crystal that controlled the coding (kinda important) - I also added a 
passive tap that I could put a counter on to pick the temperature to "zero" the
error. This allowed the spreading code to be DEAD ON no matter what the temp
was. (that crystal drifts quite a bit with temperature and causes the only 
problems with senaos- I plotted the drift in my environmental chamber and 
realized where the published specs came from) - also after kicking the power
up, it ran hot (my base runs full power ALL the time, I removed the power 
control lead when it went through an SMT resistor (now gone) - so it's always
biased at about 1.2W avg, 2.4W peak) - that extra heat was sort of unfriendly
to the crystal stability, which necessitated the cooler on it at that point.
My senao base now uses 48 VDC as the input power supply, with dc/dc converters
to get the 24, 5, and 12 V used for the watlow temp controller, the heater /
cooler, and the senao itself.  It takes about 1.8A at 48V to run it if the 
coolers are running in the summer. But that crystal is dead on!  After talking 
on it for 30 seconds or so, the coolers pretty much stay on for the whole call!

It's a work of art - I should photo it and stick it up on the web server.  
I did try running 2 bases off one timebase to see if I could get them to 
xmit at the same time and use one antenna.  NOPE.  50% same time transmit,
50% time one transmitted while the other received.  There went the single
antenna plans!  I was really hoping to get 2 into 1.

I also made 2 handsets - one that's always 1.2W, and one that's auto power
for battery life.  The handsets in the 900 series had the exact same RF deck
as the base, which made mods easy!  If you want to dig into your senaos, give
me a private email.  I don't want the lurking ham-rentacops out there getting
the mod plans.  

Everett

> 
> Dan.
> 
> 
> > 
> > Everett
> > > 
> > > I have the EnGenius (Senao) 900Mhz phone (2 1-line base units and 2
> > > handsets) and I love it.  It works about a block in my neighborhood with the
> > > base on the bottom floor in my house.  I have an omni that I've been meaning
> > > to install on the roof for greater range.
> > > 
> > > It's not rich as far as the features but it's a good phone that works well. 
> > > It does however interfere with anything that's 900Mhz.  I had an analog
> > > panasonic 900Mhz phone that I had to get rid of due to interference.
> > > 
> > > Dan.
> > > 
> > > On Fri, Oct 10, 2003 at 06:19:40PM -0700, [EMAIL PROTECTED] wrote:
> > > > My personal experience - I owned one of the first gigasets siemens came out
> > > > with ( the $200 / multi handset one)-  - the phone was miserable w/o the 802.11
> > > > and when the 802.11 came along, the phone got worse.  I opened it up and killed
> > > > the 802.11 xmitter/receiver and turned it into a $200 desk phone and answering
> > > > machine.  
> > > > 
> > > > Avoid the siemens phones and 802.11  Personal experience only.  Buy a senao 
> > > > 900 mhz 1 line or 4 line phone and be happy.
> > > > 
> > > > Everett
> > > > 
> > > > 
> > > > > 
> > > > > Anyone has Siemens Gigaset 8825 2-Line expandable wireless phone (system)? 
> > > > > How
> > > > > is it coexisting with your wireless LAN?
> > > > > 
> > > > > Apolinaras "Apollo" Sinkevicius
> > > > > Carmel Music & Entertainment, LLC 
> > > > >  web-site:  http://carmelme.com 
> > > > > ________________________________
> > > > > Having an event in Chicago, or would you like to bring Chicago entertainment 
> > > > > to your event? Give Carmel Music & Entertainment a call for the finest 
> > > > > entertainment available in Chicago.
> > > > > 
> > > > > -------------------------------------------------
> > > > > Visit CARMEL MUSIC & ENTERTAINMENT website http://carmelme.com
> > > > > --
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> > > > > 
> > > > 
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