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FT-990 & Amplifier Switching

Subject: FT-990 & Amplifier Switching
From: iadiahfd@netins.net (Larry Lindblom)
Date: Wed Dec 25 20:24:03 1996
Two of the locals in central Iowa have recently purchaased FT-990s. 
They are generally happy with these rigs but during a CW contest both
noticed the same problem.  When using the 990 to switch an amplifier,
the amplifier does not pull in until the first di or da has been sent. 
TR relay in 990 seems to fire fine, but amplifier control line is slow
to switch amplifier from standyby to operate.

They talked to the dealer (Burghart in SD) who climed no knowledge of
how to reolve the problem.  Service tech suggested bending the contacts
of amplifier relay so they were closer together and would switch
quicker!!  What a novel solution!

These guys use different ampligiers, a Titan and an AL-1200, and have
not noticed the problem with other rigs (1000D, Omni 6, IC-775, etc) so
doubt it is an amplifier problem.  Same thing might happen on SSB but
due to nature of that mode it is harder to detect.

Has anyone else noticed this problem?  If so has anyone discovered how
to resolve it?  Any help much apprreciated

73, WA0ETC, iadiahfd@netins.nst

>From aa0cy@robertwanderer.gardnerville.nv.us (ROBERT WANDERER)  Wed Dec 25 
>00:31:19 1996
From: aa0cy@robertwanderer.gardnerville.nv.us (ROBERT WANDERER) (ROBERT 
WANDERER)
Subject: log checker unionization?
Message-ID: <01BBF298.F06AC320@robertwanderer.gardnerville.nv.us>

Then of course Dave is the question of which union?
Since this is related to communications, is it the CWA?
But the work is clerical, so maybe AFL-CIO?
Hmmmmmmmmmmm.   73, Bob AA0CY

----------
From:   WJ2O@aol.com[SMTP:WJ2O@aol.com]
Sent:   Monday, December 23, 1996 11:37 PM
To:     cq-contest@tgv.com
Subject:        Re: log checker unionization?

> On 22 Dec 1996, a fellow contester wrote:
>  
>  "You CQ volunteers should get paid! After all, CQ is a for-profit 
>  enterprise, and makes money from readership interested in the 
>  contest results. 
>  
>  Just curious, has CQ ever been approached by you guys for a stipend 
>  for your hard work? Maybe you need to unionize :.)"

I have to agree that the CQ volunteers work hard, do a find job, and deserve
all the credit they can get.

However, being that I've been a self employed individual since I was a spry
lad I have to remind others that being in business dosen't mean you spend all
your time sitting back and counting your profits.  Not only is the magazine
business very competitive but the ham radio market as a whole is in decline.
 

The only thing you get as a "for-profit" business in New York State is the
privledge of paying outrageous property taxes and 7% or higher sales taxes
that I don't believe our friends at the league are accustomed too.  Also, in
our lovely state you have to pay the AMT, which stands for Alternative
Minimum Tax.  In a nutshell it means that even if you don't make a profit you
still have to pay income taxes!

I don't work for CQ, I'm not against the league (I'm a life member) and I
don't want a bunch of you guys writing me and telling me to leave NY then.
 The point I'm trying to make is that I know of no individual who has "made
it big" by selling to hams.  I do know quite a few who have gone bust though.
 Give ham radio vendors a break.  Where would the hobby be without them?

Case in point:  Once the buyers of ETO found out what selling amplifiers to
us hams was all about they dropped that division like a hot potato!

I gotta ask:  How much would it cost to get a QSL if all the bureau's
unionized?  How much would you be willing to pay for a subscription of CQ if
all the log checkers unionized?  What if it got turned around and you had to
pay say a penny for every QSO you mail in for log checking union expenses.
 Would you mind writing a check with your entries?

How's that for flame bait?  Did I take the previous message too seriously?

Happy Holidays all and see you in the next test,
73, Dave, WJ2O

(catch me in VP5 for ARRL CW)




>From trogo@primenet.com (Tony Rogozinski)  Thu Dec 26 06:00:56 1996
From: trogo@primenet.com (Tony Rogozinski) (Tony Rogozinski)
Subject: FT-990 & Amplifier Switching
Message-ID: <1.5.4.16.19961225225507.1e5706b2@mailhost.primenet.com>

Same problem here using an Alpha 76 - would like a solution 
if there is one.

N7BG



At 08:24 PM 12/25/96 -0800, Larry Lindblom wrote:
>Two of the locals in central Iowa have recently purchaased FT-990s. 
>They are generally happy with these rigs but during a CW contest both
>noticed the same problem.  When using the 990 to switch an amplifier,
>the amplifier does not pull in until the first di or da has been sent. 
>TR relay in 990 seems to fire fine, but amplifier control line is slow
>to switch amplifier from standyby to operate.
>
>They talked to the dealer (Burghart in SD) who climed no knowledge of
>how to reolve the problem.  Service tech suggested bending the contacts
>of amplifier relay so they were closer together and would switch
>quicker!!  What a novel solution!
>
>These guys use different ampligiers, a Titan and an AL-1200, and have
>not noticed the problem with other rigs (1000D, Omni 6, IC-775, etc) so
>doubt it is an amplifier problem.  Same thing might happen on SSB but
>due to nature of that mode it is harder to detect.
>
>Has anyone else noticed this problem?  If so has anyone discovered how
>to resolve it?  Any help much apprreciated
>
>73, WA0ETC, iadiahfd@netins.nst
>
>
                                



                           Tony Rogozinski N7BG
                          One of the "Voo-Dudes"
                           VooDoo Contest Group
                 I Collect TELEGRAPH KEYS - Especially "Bugs"    
          Call Me At 1-800-966-6264 if you have any to sell or trade
                  I usually have some duplicates for sale


>From eschwab@sime.com (Michael Schwab)  Thu Dec 26 09:33:03 1996
From: eschwab@sime.com (Michael Schwab) (Michael Schwab)
Subject: Contest Location
Message-ID: <199612260932.KAA26122@arctica.sime.com>

This is not directly related to contesting. 
However, if you consider spending a Contesting/DX-ing holiday in Europe,
a charming location in Austria, near a romantic medieval town, is for rent 
during several weeks in 1997. 
If interested, pse contact OE6MBG. E-mail address: eschwab@sime.com
  

>From john.devoldere@innet.be (John Devoldere)  Thu Dec 26 12:14:53 1996
From: john.devoldere@innet.be (John Devoldere) (John Devoldere)
Subject: conversion to grid square.
Message-ID: <199612261213.NAA07890@mail.be.innet.net>

CAn anyone help me?

My location is 51 deg 00 min Northm, and 3 deg 45 mins East. What is my grid
square?

73

John, ON4UN

----------------------------------------------------------------------------
john.devoldere@innet.be
Call us in all major 1997 contests: ON4UN or OT7T
John Devoldere (ON4UN-AA4OI)
POBOX 41
B-9000 Ghent (Belgium)


>From ke7gh@primenet.com (Brian Short)  Thu Dec 26 14:35:43 1996
From: ke7gh@primenet.com (Brian Short) (Brian Short)
Subject: FW: Non QSK Switching the FT-990
Message-ID: <01BBF33A.F27AAFC0@ip020.phx.primenet.com>

In the course of operation, in CW and RTTY, I have noticed 
the occasional fast flashing of the HI SWR light on the FT-990 
when first keying for a transmission.  

This I came to recognize as the amplifier relay not activating 
as quickly as the FT-990.  Using the N6TR logging program, this 
was NOT the case because of the PTT signal used by the program 
to prevent such timing problems.  Since I don't always use the 
N6TR logging program (e.g. in RTTY mode) I became concerned for 
two reasons: 1) long term effect on rig and relay, and 2) effect 
on Dunestar band pass filter in line to the amplifier.

My solid state QSK FL-7000 amp had employed the FT-990 TX inhibit 
signal (INH) present on the BAND DATA jack to interlock the amp and 
rig. A simple RC network on the INH signal could disable the rig for 
the desired amount of time, allowing the amplifier relay to ALWAYS 
completely energize before enabling the transmitter.

The precise time constant needed is tricky!  There are two conflicting
requirements: 1) switch slowly enough to allow the amp relay to close,
but 2) switch fast enough so that the first dit, even QRQ is not missed.
For this reason, others may want to tailor slightly the values of the
two 1k resistors in parallel comprising the R of the RC network.  These
values work for me...

NOTE:  MY AMP USES A +12V KEY RELAY.  DO NOT USE THIS CIRCUIT WITH
       AMPLIFIERS EMPLOYING NEGATIVE OR HIGH VOLTAGE KEYING!


FT-990 BAND DATA                                                     AMP
----------------                                                     ---

PTT >----------------------------------------------------------+
                                                               |
                                                               |
                                                               |
                                  1k*          1N4001          |
INH >-----------+-----------+---/\/\/\/\---+----->|-------+----+----> PTT
                |           |              |              |
                |           |      R       |              |
                |           |              |              |
               ---          +---/\/\/\/\---+---/\/\/\/\---+
             C --- 10uf            1k*           3.3k
                |
                |
GND >-----------+---------------------------------------------------> GND

*NOTE: Slight adjustment of these resistors may be necessary to 
       establish the exact timing you desire.  Remember: T=RC.

I now use the above circuit with my FT-1000MP also.  Months ago, someone
sent me an alternative solution that used a capacitor in the PTT line to
charge during RX and discharge quickly at the beginning of TX.  Used with 
a 12v relay in the amp, this causes the relay to switch a bit faster 
(apparently).  My copy of that seems to be missing right now.

73 de Brian ke7gh@primenet.com



>From kt4ld@juno.com (ANDREW H LEWIS)  Thu Dec 26 14:54:44 1996
From: kt4ld@juno.com (ANDREW H LEWIS) (ANDREW H LEWIS)
Subject: Can someone Help me with the MFJ voice Keeyer
Message-ID: <19961226.105803.4447.1.KT4LD@juno.com>

As a Christmas gift my parents gave me an MFJ Voice keeyer. It is a
welcome addittion under the tree.  However the Keyer is the MFJ #432 and
it came with an 8 pin connector to go into the mic. My rig only accepts 4
as it is a very old rig (Kenwood TS820S). Does anyone, perhaps, know of
anyone or themselves that knows how to hook it up? Is there a connector
I'm missing?  Maybe there's a converter? Merry XMAS and thank you so
much.

                            73
                           K4HQ
*********************************************************************************************
Andrew Lewis            16 YEARS OLD        
Formerly: KE4LJM, KE4LJM/NA 067, KT4LD
Past operations: ZF2/KT4LD, ZF8ZP, ZF2ZX, 6Y5NR, 6Y5/KT4LD, XE/KT4LD,
XE9LD, KT96LD, KT400LD, KT26LD
QSL Manager for: TF/WF0E, HS0E, HZ1ZM, TF2YE
--------- End forwarded message ----------


>From bigdon@eskimo.com (Big Don)  Thu Dec 26 14:59:16 1996
From: bigdon@eskimo.com (Big Don) (Big Don)
Subject: FT-990 & Amplifier Switching
Message-ID: <Pine.SUN.3.95.961226064032.4805B-100000@eskimo.com>

On Wed, 25 Dec 1996, Tony Rogozinski wrote:

> Same problem here using an Alpha 76 - would like a solution 
> if there is one.
> 
> N7BG

You might try the Poor Man's QSK we have been using here at Big Don.
You key the amp with a footswitch, the transceiver never knows what's
going on. Just hit the amp a hair early and your first dit/dah will get
thru unscathed and amplified.  With an SB-220, at least, there is
sufficient RF leakage thru the amp relay, that you can copy QSK on the
transceiver with the amp keyed, you lose mebbe 20-40 db, but you can
usually tell if the DX is transmitting, which is what you need to know.
(OK you Alpha owners, stop ROTFL...)

Was a little concerned when first tried this that some switching spike
from the amp might kill the xcvr front end if the xcvr was still in rcv
when you key the amp, but this has worked fine for 4 years with a TS-440
and 6 more years with a 950. YMMV.

Big Don
http://www.wsu.edu:8080/~garya/uncle.html




> 
> 
> 
> At 08:24 PM 12/25/96 -0800, Larry Lindblom wrote:
> >Two of the locals in central Iowa have recently purchaased FT-990s. 
> >They are generally happy with these rigs but during a CW contest both
> >noticed the same problem.  When using the 990 to switch an amplifier,
> >the amplifier does not pull in until the first di or da has been sent. 
> >TR relay in 990 seems to fire fine, but amplifier control line is slow
> >to switch amplifier from standyby to operate.
> >
> >They talked to the dealer (Burghart in SD) who climed no knowledge of
> >how to reolve the problem.  Service tech suggested bending the contacts
> >of amplifier relay so they were closer together and would switch
> >quicker!!  What a novel solution!
> >
> >These guys use different ampligiers, a Titan and an AL-1200, and have
> >not noticed the problem with other rigs (1000D, Omni 6, IC-775, etc) so
> >doubt it is an amplifier problem.  Same thing might happen on SSB but
> >due to nature of that mode it is harder to detect.
> >
> >Has anyone else noticed this problem?  If so has anyone discovered how
> >to resolve it?  Any help much apprreciated
> >
> >73, WA0ETC, iadiahfd@netins.nst
> >
> >
>                               
> 
> 
> 
>                            Tony Rogozinski N7BG
>                           One of the "Voo-Dudes"
>                            VooDoo Contest Group
>                  I Collect TELEGRAPH KEYS - Especially "Bugs"    
>           Call Me At 1-800-966-6264 if you have any to sell or trade
>                   I usually have some duplicates for sale
> 
> 


>From w2vjn@rosenet.net (George Cutsogeorge)  Thu Dec 26 23:36:14 1996
From: w2vjn@rosenet.net (George Cutsogeorge) (George Cutsogeorge)
Subject: FT-990 & Amplifier Switching
References: <32C1FDE3.6BE2@netins.net>
Message-ID: <M.122696.153614.55@ppp003.rosenet.net>

Antenna switch over is too slow in some combinations of radio and amplifier 
because two relays must switch in sequence.  First the radio relay must pull in 
then the amplifier relay pulls in.  The delay in the radio relay can be 
eliminated with a very simple circuit.

If the amplifier relay requires a "ground" to operate, a diode OR gate can be 
used to start the amplifier relay pulling in when the key is pressed without 
waiting for the radios relay to pull in.  Two diodes are required.  The two 
cathodes are connected together and to the key.  One anode connects to the 
radio key input.  The other anode connects to the amplifier relay along with 
the radio amplifier relay control.

When the key is pressed, the amplifier relay immediately starts to pull in.  A 
few milliseconds later the radio amplifier control relay pulls in and holds the 
amplifier relay in during the spaces between dots and dashes.  Most well 
designed radios have a few milliseconds of delay after the key is pressed 
before the RF output starts up.  For example: the IC765 has about 7 
milliseconds delay.  The Titan amplifier uses an RJ1A vacuum relay which takes 
only about 2 milliseconds to pull in.  This leaves a safety period of 5 
milliseconds before RF starts if the OR gate technique is used.  

I have been using this method for full qsk with several different radios and 
home made as well as commercial amplifiers for many years.  If the amplifier 
relay is very slow, and does not pull in before the RF starts, this method will 
probably not work and a foot switch is needed.  Any diodes that will carry the 
relay drive current will work.  Typically, 1N4001s will be OK.  

If the radio has a voltage output that switches on transmit with no delay when 
the key is pressed, another simple method may be used.  The voltage can be used 
to control a power transistor or FET which then pulls in the amplifier relay.  
This will eliminate the delay in the radios amplifier control relay.  I used to 
use this technique with home made amplifiers and the 930/940 radios.

In extreme cases a circuit which delays the key closure to the radio while 
sending the undelayed closure to the antenna relay is needed.  

George
----
George Cutsogeorge,  W2VJN                   
Umpqua, OR.
http://www.qth.com/topten


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