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Re: Re: TS-2000X



on 2/4/03 8:22 AM, kevin schuchmann at kschuchm@pacbell.net wrote:

>> 
>>> Not guilty??...give me a break... you dont need a 14 foot dish to uplink to
>>> AO40 on L band, if you use one fine... if your beacon
>>> level turn it down, cant go any lower? then DUH guess you shouldnt be using
>>> a
>>> 14 foot dish on uplink and yes you are guilty.....
>>> ever hear of a attenuator???
>> 
>> Gee, perhaps the guy has one setup for EME and AO-40.  It's not so easy to
>> add attenuation in just one path.
> 
> and how is that ao40's problem????? its the operators problem...
> this is almost a social issue... everything is someone elses problem these
> days... not mine...

I NEVER said it was AO-40's problem.  In fact, there's no problem at all.
Yes, it's an issue if there's a lot of people on and the transponder power
is being hogged by one or two guys.  But the facts are that there's
generally only a handful of Qs going on at any one time.  Last night, I
called CQ for a good while and never had anyone come back.  I think there
were maybe 4 Qs going on total not counting any CW as I wasn't looking for
that.

> 
>>> and from what I have seen both sides are guilty...  so I wouldnt go finger
>>> pointing .....
>> 
>> Oh yeah, I'm one of those people who are running a BBQ dish.  I'm not
>> supposed to be able to hear well....Yet, I hear fine.  Work stations all the
>> time when squints are above 20 degrees.
> 
> I have had a bbq grill, 50 element looper, 3 foot dish ,4.5 foot dish, and 6
> foot dish....
> maybe your not hearing as well  as you think you are....

Huh?  Is my receive set up perfect?  No.  Yet I see a lot of people claim
that a 60 cm solid dish will give far better results than a 3 foot by 2' BBQ
dish.  Yet, 60 cm is approximately 2 feet.  Other than the fact that the
solid dish provides CP and perhaps a better, feed, the area of the BBQ dish
is significantly larger.  I plan on changing the feed and making the BBQ
dish into a CP capable reflector once the WX warms up.  I certainly want to
improve my SNR.

But to say that I am not hearing well is just ludicrous.  I hear the beacon
at a level of S7 to S8.  I am able to copy just about anyone on the bird
including guys at the noise floor.  Perhaps its due to the fact that I work
a lot of weak stations on HF and don't expect the bird to sound like my
local FM repeater. 

Now conventional theory is that each S unit is about 6 dB.  But let's throw
that out the window because it's probably just not accurate.  Let's say that
each S unit is more akin to 2 dB.  OK, if I hear the beacon at S8, then a
station 10 dB below the beacon would be at S3.  I hear virtually NO ONE but
some L band stations that loud.  Most guys are at S1 or S2 at best.  Perhaps
you in your Boy Scout wisdom will counter that my S-meter is not linear.
Perhaps not.  After all, you know what I hear and my system better than I
do.

Let's see, last night I worked CT1BOY quite easily.  Squint was around 20
degrees.  For him, the bird was barely above the horizon.  Gee, I thought I
couldn't hear.  Yet, his signal was solid and quite comfortable.


> I know that my 
> receive setup
> is so much better than when I started, yet I had plenty of qso's on the bbq
> depending on which antenna I'm using I get 6-9 db of xpondr noise and the
> beacon is 18-21 db above that
> 
No doubt.  And part of ham radio is all about improving one's station over
time.  So what S-level do you receive the beacon?  It's not all the
meaningful from receiver to receiver, but it's the only relative measure we
have.  Telling me you are 18 to 20 dB above the noise floor is great, but I
have no reference to that.


>> 
>> In my experience on AO-40, I find VERY few people running anywhere near the
>> beacon.  Supposedly, the "experts" say that a BBQ dish doesn't cut it.
>> Well, it does.  I get the beacon very loud and can work stations down to the
>> noise floor.  Most stations are a couple dB above the noise floor but they
>> are WAY more than 10 dB below the beacon.  I've never heard anyone calling
>> CQ on top of the beacon.  It's so loud, I can't believe anyone with any kind
>> of S band antenna can't hear it.
> 
> I have heard cq on the beacon... have reported it to the irc channel and
> others have heard it...
> and it has happened more than once...  would you like callsigns???

Well, then they must have squat for a receive set up if they can't hear the
beacon or they just must be incredible lids.  I could probably hear the
beacon just fine and CW for that matter if I used my corner reflector for
AO-40 as opposed to my dish!  It's either that or they just don't know how
to operate.  Perhaps they have some desense problems when they transmit and
can't hear their downlink.  Perhaps they have no idea of where they are.
They may actually be able to hear just fine, but have other problems.

Yet so quick we are to say that most people can't hear squat.  I think
that's a very silly attitude and when people with simple setups read that it
will scare them away from ever even trying to get on AO-40.  If I didn't
know better, my common perception from reading statements like yours is that
you need a much more sophisticated setup.  This is one of the reasons why I
took the survey of people who are using the AIDC downconverters.  Many
people are using them on BBQ dishes or Primestar style dishes and are having
fine results.  I'll be compiling my results soon and I think it will show
that the "common" Boy Scout wisdom is not quite so accurate.

> 
>> 
>> Have I tripped Leila before?  Yes, I have.  But yet, I've done it when
>> running only a few watts.  Oh yeah, shame on me.  40 elements on the UHF
>> uplink is too many.  Leila, IMHO, tends to trip sometimes when it shouldn't.
>> We all know that.  So while it's a good judge of your power, it's not 100%
>> reliable either.  The vast majority of stations on AO-40 do a very decent
>> job of staying below the beacon.  Yes, the L-band guys are generally
>> stronger, but that's not necessarily their fault.  The L-band receiver on
>> the satellite just tends to work better.
> 
> Jon its entirely their fault, I can run my U or L from the noise floor to
> beacon level
> I'm in control of my station... I really disagree that its not their fault if
> they are too strong...

So you ignore the fact that the U band AGC tends to pump a lot more than the
L band AGC even though the L band signals are much stronger?  Look at the
telemetry from the bird.  And I've noticed that when there is a lot of
activity on the bird, the U band receiver has difficulty.  I noticed that
the first day I got on AO-40 and there weren't a lot of people running
excess power.  Perhaps it has to do with the ground radar issues and that it
tends to compress the AGC.  I don't dispute that you are in control of your
station.  So am I and I operate accordingly.  And I think you take my words
out of context.  I firmly believe that the L band RX on the bird works much
better than the U band RX and that is one of the reasons the L band ops have
better signals.

73,

Jon
NA9D

-------------------------------------
Jon Ogden
NA9D (ex: KE9NA)

Citizen of the People's Democratic Republik of Illinois

Life Member: ARRL, NRA
Member:  AMSAT, DXCC

http://www.qsl.net/na9d   <- Updated on 1/22/03!!!

"A life lived in fear is a life half lived."


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