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Amplifier Problem

Subject: Amplifier Problem
From: Jastaples@aol.com (Jastaples@aol.com)
Date: Sat Jun 15 11:56:20 1996
While operating the All Asia contest today I noticed that when I use the
SB-220 amplifier the received signal drops by 20 db or more. 

While I seldom use this amplifier, it may remain off for months on end, it
has always been a reliable perfomer with no quirks or "strange things"
occuring. But now it wants to act as a receive attentuator when switched on.
(It works fine as an amp... 1 KW or more  out with modest drive and grid
current). 

I can visualize things like bandswitch contacts, tube plate cap and socket
pins, etc, needing to be polished up, or maybe even a solder joint gone bad.
But perhaps someone has either had the same experience or has a neat
suggestion for a fix.

Please reply direct...

Thanks, Joe, W5ASP

>From txt@canit.se (Torgny)  Sat Jun 15 16:11:30 1996
From: txt@canit.se (Torgny) (Torgny)
Subject: Why vanity calls on contest reflector?
Message-ID: <199606151511.RAA08320@uno.canit.se>


>For instance, CA held the record once for the greatest number of Club calls 
>issued to 4 individuals ( 17 ). Unfortunately, it only held for a few weeks
when
>it was replaced by a TX family of 4 who now hold 24 different club calls. I

 Why am I not surprised? Only in america...   :-)

 /Torgny - SM0TXT
 



>From ki3v@rnodx.org (Richard Hallman)  Fri Jun 14 16:42:49 1996
From: ki3v@rnodx.org (Richard Hallman) (Richard Hallman)
Subject: Callsigns
Message-ID: <31C1887D-00000001@rnodx.org>


   What concerns me is that we currently should ONLY have ONE callsign for
our personal use.  I have noted MANY abuses to the so called " CLUB
CALLSIGN group".   A perfect example was during the CW Sprint when many
elected to use THEIR Club callsign (2X3) for the contest.  Several had
already commented on the status and members of those clubs.

  My wife is also a ham and I COULD have requested a PERSONAL Club
callsign, But I elected not to.  After all the gates are finished,  lets
see how many actual CALLSIGNS some of us have.  One for CW Sprint, one for
SS and one for on the repeaters....ect.   

If you want a NEW call.....Give up the one you NOW have!!!  Dont hold a
handful of them for your OWN use!!

I think we should have ONE callsign...Period!!   Not two or more.....


 So, before you start throwing rocks in someone elses back yard for being
callsign HOGS.....You better look back in your own!!


  Maybe somebody should provide a list here of all the 2 person Clubs that
was formed by the "Elite" contesters and lets see how many calls they end
up with.....I sure dont see the fairness of this practice.
 
                                 

                                                Rich  KI3V 

**********************************************************
Richard Hallman               ki3v@rnodx.org
11870 Heartpine St           
Reno Nv  89506               ki3v@w7ta.#nonev.nv
**********************************************************


>From aa8u@voyager.net (AA8U)  Sat Jun 15 17:47:33 1996
From: aa8u@voyager.net (AA8U) (AA8U)
Subject: "Ugly-as-L" DXpedition Antenna
Message-ID: <199606151647.MAA22509@vixa.voyager.net>

I have been building an antenna to take on a DXpedition in July to the South
Cook Islands. I have received many requests for dimensions and construction
details since this design was first mentioned on the reflector. 

This design evolved from a simple 160M inverted-L to its present four-band
form, as I realized we would likely have some restrictions placed on the
number of antennas we could erect at the Rarotongan Resort Hotel. 

The first 160M version was a straight forward 234/f length antenna with 60'
vertical and the rest horizontal. It only had 5 ground radials, each 133'
spread out and laying on the ground. It was fed with a 28:50 ohm Un-Un
(W2FMI design). 
As I added traps to get additional bands, the overall length decreased. I
think the single band antenna would probably perform slightly better than
the final version. 

Bandwidth is adequate on the final version, but not generous, except for the
narrow 30M band. 

Ground losses for this design haven't been measured. 

The feed point resistances and SWR figures below were obtained at the feed
point using an MFJ-259 Antenna Analyzer. A real nifty piece of test
equipment!!! It has a calibration error on the bands tested as indicated in
the notes below. It does give reliable indications when this factor is taken
into account.  

On the air comparisons have been made between this antenna on 160M and my
full size insulated base 25G vertical with 30K' of radials under it. The
DXpedition model seems to get within about 6 to 10 dB (here to the east
coast regulars on 1850) of the full size counterpart. Separation between
these two antennas is about 1000'. 

I present the final dimensions here that others might save themselves a
couple of saturday mornings for GOLF or some other activity. Building this
one and getting it to work should be a snap. If I had known how easy and
simple it was to do this, I would have done it many years ago.


 Dimensions To Trap Centers         Fo         SWR                  Feedpoint R
-------------------------------------------------------------------------------
Feed point to KW-30    = 21' 4"   10.12 mHz.  1.10:1                      50
KW-30 to KW-40         =  7' 8"    7.05 mHz.  1.15:1                      44
KW-40 to KW-80CW       = 23'       3.61 mHz.  1.20:1                      36
KW-80 to end insulator = 39' 1"    1.83 mHz.  1.60:1/(1.0:1 w/28-50 unun) 28

MFJ-259 resistance calibration: 50 ohms = approx. 42 ohms actual @ 1.0:1 SWR.

Feed point 1' 6" above ground, mounted on short ground rod 2' in earth.

Radials: 5 @ 133'
         5 @  68'
        10 @  33'

Wire use for the radiator and radials is #14 MTW (600 V Insulation). Using
bare copper wire for the radiator will be require these dimensions to be
increased by about 2%. 

################################################################################
#   The "Ugly-as-L"  160/80/40/30M   DXpedition Inverted-L Antenna             #
#                       Designed and tested by AA8U
#
############################################################################
#### # Tall
Tall # # Tree             HI-Q Insulator               HI-Q Insulator
Tree # 
# O----5/32" Dacron-----====..........39'1".........====------5/32"Dacron----O #
#                          [=] KW-80CW
# 
#                           :                                                  #
#                           :
# 
#                           :                                                  #
#                           :   23'                                            #
#                           :                                                  #
#                           :                                                  #
#                           :                                                  #
#                          [=]  KW-40
# 
#                           :                                                  #
#                           :    7' 8"                                         #
#                           :                                                  #
#                          [=]  KW-30
# 
#                           :                                                  #
#                           :                                                  #
#                           :   21' 4"                                         #
#                           :                                                  #
#                           :                                                  #
#                           X  feed point   (w/28:50 Un-Un on 160M)            #
#                           :    1' 6"
# 
#   _____________________radials________________________                       #
#                      (on ground)                                             #
################################################################################

If you build one, let me know how this design works in your environment.

73 to all,

Bruce (AA8Ugly  ZK1AAU)

aa8u@voyager.net

President: Mad River Contest Club


>From jreid@aloha.net (Jim Reid)  Sat Jun 15 18:27:53 1996
From: jreid@aloha.net (Jim Reid) (Jim Reid)
Subject: Why vanity calls on contest reflector?
Message-ID: <1.5.4.32.19960615172753.0069df6c@aloha.net>

At 07:55 AM 6/15/96 -0400, you wrote:
>
>
>Why is this barrage of comments on vanity calls on the contest reflector?

Probably because a lot of the folks find it an interesting topic;
a lot of changed call signs by contesters will impact operating
strategy/tactics of the medium and big guns. They now recoginze
a lot of calls/fists/voices real fast in the heat of competition,  but
with the calls a-changing......?

73,  Jim, AH6NB


>From wb2nqt@usa.pipeline.com (Mark Sihlanick)  Sat Jun 15 19:30:56 1996
From: wb2nqt@usa.pipeline.com (Mark Sihlanick) (Mark Sihlanick)
Subject: Amplifier Problem
Message-ID: <199606151830.SAA08536@pipe11.h1.usa.pipeline.com>

Take a look at the contacts on the antenna relay.  Its an open frame type
and without any "wetting" current to flow through it has probably built up
some oxidation.   I've usually used some typing paper to clean the contacts
and soaking with contact cleaner also helps some. 
 
Good luck 
Mark 

>From jbmitch@vt.edu (John Mitchell)  Sat Jun 15 19:21:36 1996
From: jbmitch@vt.edu (John Mitchell) (John Mitchell)
Subject: Amplifier Problem
Message-ID: <199606151833.OAA22485@sable.cc.vt.edu>

At 10:56 AM 6/15/96 -0400, Jastaples@aol.com wrote:
>While operating the All Asia contest today I noticed that when I use the
>SB-220 amplifier the received signal drops by 20 db or more. 
>


Hi OM,

The only thing that I've had cause this is a stuck transmit/receive relay;
the receive signal going thru the final stage is down about 20 db on HF.

73 es GL

de WD4MUR


>From slazar19@sgi.net (Spike Lazar)  Sat Jun 15 19:40:24 1996
From: slazar19@sgi.net (Spike Lazar) (Spike Lazar)
Subject: Callsigns
Message-ID: <199606151840.OAA17413@orion.bv.sgi.net>

RE: KI3V, (snipe)

>   What concerns me is that we currently should ONLY have ONE callsign for
>our personal use.  I have noted MANY abuses to the so called " CLUB
>CALLSIGN group".   A perfect example was during the CW Sprint when many
>elected to use THEIR Club callsign (2X3) for the contest.  Several had
>already commented on the status and members of those clubs.
>
>If you want a NEW call.....Give up the one you NOW have!!!  Dont hold a
>handful of them for your OWN use!!
>
>I think we should have ONE callsign...Period!!   Not two or more.....

-----------------------end of Rich  KI3V, remarks------------------------- 

Dear Rich,

I really didn't give too much thought to your post, and I checked it
out for myself, I rounded up 10 of the usual suspects and your right,
7 of them had an additional call/calls (club) and one had two additional
calls.

There has been a lot of whining about this, I'm sure there must be a 
good reason for these second and third calls. So before we judge, I'm
sure some of these folks will add to this thread, by coming forth with
the real scoop, maybe they will even convince us to join rank with them!

On the other hand, they have probably not opted for that new spiffy call
yet, and may just decide to keep that (club) "clunker" and give up their
old trade mark!

Now that is the guy I can really respect, he can now beat the shinola
out of me in contests with both his hands tied behind his back!

Sincerely your,
dr. Bafoofnik
p.s, I could see K3ZO opting for K3 "OZ", or K3EST opting for K3 "E S E"


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