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FD freebie xmtrs

Subject: FD freebie xmtrs
From: KA9FOX@aol.com (KA9FOX@aol.com)
Date: Wed May 18 18:49:41 1994
  > In general, I think it is time for ARRL to 
  > abandon the present free-transmitters in FD.
  > ...This leaves the question of how to use the 
  > current "one transmitter on the air" in the 
  > wisest possible fashion as a strategy 
  > decision for each FD teams.                   
 
Unfortunately, with the 10 minute rule on band changes, the strategy would
effectively be to abandon all packet radio efforts.  While we don't make a
ton of packet QSOs, it does give some of the contest-disadvantaged in our
group a way to get involved in scoring points during the contest.  Guess now
I'll have to get out of my chair and let them S & P on phone for a while :-0

73 Scott KA9FOX
(W9UP field day)

ka9fox@aol.com


>From Cleve D Leclair <dleclair@efn.org>  Wed May 18 21:57:22 1994
From: Cleve D Leclair <dleclair@efn.org> (Cleve D Leclair)
Subject: Ground Window
Message-ID: <Pine.3.89.9405181345.A26579-0100000@efn.efn.org>

   I'm not a "new" ham, but I do remember in my novice/tech days, 1978
thru 1985, that we wud tell any/all stns contacted to "qsl via the buro".
I did not qsl thru the buro, but I hurd sevral others do this...
Why shouldn't we use, in my case, the 7th area qslburo for any and all
incomming cards???

   Cleve - N7IXG


>From John W. Brosnahan" <broz@csn.org  Wed May 18 23:24:55 1994
From: John W. Brosnahan" <broz@csn.org (John W. Brosnahan)
Subject: FT-1000 audio
Message-ID: <199405182224.AA22193@teal.csn.org>

FT-1000 AUDIO
 
The following message was posted yesterday, but was never received by me
and I now believe that it wasn't distributed on the reflector.  If it is a 
duplicate, my apologies.  I have now seen a second message by KG7D that seems
to indicate he has received some additional input, and I have added some
more comments after the retransmission of the message below. 
 
_______________________  MESSAGE FROM YESTERDAY BELOW
 
To: Bob, KG7D
 
I am afraid you have missed the point about the Heil headphones and the Yaesu
FT-1000.  Because of the wimpy audio driver IC in the Yaesu only very
efficient headphones with the exact right impedance will have enough
audio.  Heil has tried to redesign his headphones to accommodate the 
limitations of the FT-1000 and Yaesu has now changed the output resistor to
provide a little more output, but any series resistor in the radio 
means that lowering the headphone impedance beyond a certain point will
result in less audio not more from the Yaesu.  Even with the lower
impedance drivers from Heil the audio is still only adequate at best.
 
Heil headphones work fine with other radios that have an adequate audio
amplifier and no series resistors, because they use the speaker 
amplifier (about 3 watts) to drive the headphones.  It is just that Yaesu
needed a stereo amplifier to accommodate the two receivers and the speaker
amplifier is only a mono amp so they added a separate stereo headphone
amp and tried to get away with a little 100 mW IC that is OK with some
headphones, but not all.  Yaesu (USA) is aware of the problem and Yaesu
(Japan) SEEMS to be aware of the problem since they have made a design change
in the value of the series resistors, but the amplifier is really marginal,
at best, on both power output before the THD becomes excessive and on gain.
 
I am looking at ways to easily make improvements in the RADIO, which is the 
limiting factor.  Heil has lowered his headphone impedance to accommodate
the recent modification by Yaesu that lowered the series resistor but in fact
the lower impedance headphone drivers may result in LOWER audio when
using older FT-1000s.  I feel Heil has bent over backwards to try and
accommodate a marginal design from Yaesu.  ANd my mission is to try and 
understand the problem, which I do now, and find as simple a way as
possible to improve the results when using the Heil headphones with the
Yaesu FT-1000.
 
Stay tuned for the next exciting adventure in the pursuit of enough
audio to make up for my years in the sound reinforcement business.
 
73  John  W0UN     broz@csn.org
 
------------------ADDITIONAL COMMENTS
 
Back when all radios and stereos systems fed their headphones from the 
speaker jack and before the advent of battery operated headphone equipment, 
all of the headphones were of a high enough impedance so no damage would be 
done with the gain cranked up.  Efficiency wasn't an issue either.  
 
Now that there are so many low powered devices with low battery voltages 
(and therefore low audio voltage swings) more efficient and lower impedance 
phones have become a necessity.  
 
Since Yaesu is the only radio manufacturer that I know of that uses a
separate headphone amp from their speaker amp and the headphone amp
is based on a chip that is designed to drive high efficiency headphones
with low voltages it becomes an issue as to which phones work and which 
don't.  Heil has made a good effort to be accommodating, but at this 
point I want to actually quantify relative efficiencies and impedances
so that I have a real handle on the issues.  I will mount a microphone in
a can as a way of coupling to the headphones in a closed box to make
some real measurements.  Will be interesting to see what the numbers
work out to be.  Nothing on any absolute scale, just relative levels and 
will probably use white noise to reduce any effect of frequency response.
 
Additional Notes:
 
1)  The series resistors do provide for the use of mono phones in the stereo
jack, but that would be a waste on the FT-1000 since the second receiver
would not be useable.  And the resistors do provide short circuit
protection, but many or most modern audio amps have short cricuit protection
built it.
 
2)  Fortunately the audio impedance of headphones is pretty close to the
DC resistance, but I will do all of my comparisons based on impedance at
700 Hz, after making enough measurements to confirm that the impedances
of the various headphones are flat over the ham audio spectrum.
 
73  John  W0UN    broz @csn.org
 
 

>From oo7@astro.as.utexas.edu (Derek Wills)  Wed May 18 23:33:35 1994
From: oo7@astro.as.utexas.edu (Derek Wills) (Derek Wills)
Subject: domestic bureau
Message-ID: <9405182233.AA07737@astro.as.utexas.edu>

        I'm not a "new" ham, but I do remember in my novice/tech days, 
        1978 thru 1985, that we wud tell any/all stns contacted to "qsl 
        via the buro".

I suppose there was a domestic bureau at one time, but there isn't
one now.


        Why shouldn't we use, in my case, the 7th area qslburo for any 
        and all incomming cards???

           Cleve - N7IXG

Why shouldn't you volunteer to help the overworked ARRL bureau card
sorters who are kept busy sorting all the international outgoing
and incoming cards?   I suspect the volume of cards would be pretty 
high if you could send domestic cards that way, since many people make 
predominantly W-to-W contacts.   Most of the people on this reflector 
are probably like me, and rarely make contacts with Ws outside contests, 
but we are in the minority.   

I believe there have been several domestic QSL bureaux on and off
through the years, but I'm not aware of one in operation in the
last few years.


Derek AA5BT oo7@astro.as.utexas.edu 

>From Dave Pascoe <pascoe@MathWorks.Com>  Wed May 18 23:51:12 1994
From: Dave Pascoe <pascoe@MathWorks.Com> (Dave Pascoe)
Subject: January VHF Contest results?
Message-ID: <Pine.3.89.9405181851.B6216-0100000@zippy>

I just renewed my ARRL membership but apparently won't get June QST until 
2-3 weeks into June.

If someone already has it, could you e-mail me the Top 10 Single-Op All 
Band, Top Single Op 144 MHz, and Top Multi-Op scores?

TIA,
-Dave KM3T

>From P.VASILION" <V111QHEG@ubvms.cc.buffalo.edu  Thu May 19 02:20:54 1994
From: P.VASILION" <V111QHEG@ubvms.cc.buffalo.edu (P.VASILION)
Subject: Domestic QSLs through bureau
Message-ID: <01HCHWRR36NM8X18YX@ubvms.cc.buffalo.edu>

According to my sources, a domestic station can send domestic cards via
a _call district buro_.

This means that I can get a bunch of cards for 0-land stations together
and send them to the 0-land QSL bureau, but not via the ARRL Outgoing
QSL Bureau.

Likewise, if I get a card from a domestic station via the 2-land
call area buro, I can only send a reply card to his district bureau --
if he's a W2 I have to send the card directly to North Jersey DX Assoc,
which is not bad since I send correspondance to them all the time. If
he's from another call district it can be a hassle.

Hope this clears it up.

73
Peter KB2NMV
Vice President, Western NY DX Assoc.
President, Univ. at Buffalo ARC.

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