[AMPS] Ameritron QSK-5 amp switch

[Jim Reid]

Hi again,

This is long,  so don't bother to read it unless you really
care,  hi.  Bottom line:  I believe I now have the Omni,
the QSK-5 and the linear all happily working,  timed
correctly,  and full rcv signal amplitudes!  Read on to learn
the tortuous story.

Thank you for your note,  Phil, K5PC,  who wrote:


> Jim, are you sure these bulbs are the right voltage (6.3v)
> and current (150 mA) ?

The 6.3 v,  150 to 200 mA fuse bulb value was suggested by
Joe Subich, K4IK. and they seem fine.  However,  he urged
using Chicago Miniature bulbs;  the Radio Shack here on Kauai
didn't have those,  hi.

Well,  they are to act as fuses,  not light bulbs,  hi.  Anyway,
they do work:  I have managed to already "blow" one pair
of my new bulbs.  They were doing fine,  that is doing their
"flashing" bad timing routine with CW characters.  Then I
tried keying the PTT on the mike;  big mistake,  the bulbs
emitted a brilliant flash as the filaments popped open.  So
I unscrewed them from the sockets and put in two new ones.
Pleased I took the time to add sockets, hi.
 
Phil continued:
 
> Jim, why are you using the hook-up from figure 2C? It plainly states
> that this is for NON-QSK transceivers. I think the Omni is way too fast
> for this lash-up.

It was the only diagram of the three that it seemed I could understand
and implement.  However,  there is still a timing problem,  and I believe
I now have found it.  To quote a couple lines from the -5 manual:

" The transceiver MUST have the proper sequencing of the  RF and
QSK output lines.  The transceiver QSK line must pull low BEFORE
RF appears on the output connector and release AFTER the RF
envelope reaches zero to operate with any QSK switch."

Also,  it seems the Key 1 input jack must go low immediately with
key down as this is what closes the linear amp relays.  A "ground"
input signal to Key 2 is what changes the diode gates from
rcv to xmit,  and THEN AUX is pulled low.

It seems to me to make no sense to wait for AUX to go low to
generate an input signal to Key 1!  Connecting Key 1 directly
to the keyer,  a la fig 2c,  seems to me to be the correct connection.

But,  how do you get the transceiver to stop putting out RF 
BEFORE the QSK line goes low???  In both fig 2a and 2b
connections,  the QSK line is used as the input to Key 2!  So,
yes,  this would keep the gates set to xmit until the QSK line went
low.  

In the case of figs 2a and 2b,  your keyer connects directly to
the key input of the transceiver.  The Key 2 line connects to
the transceiver QSK line.  This QSK line must be a
wire which goes low with the key signal,  but somehow stays
low until sometime after the key is up,  and RF output from
the transceiver has stopped.  

What connection to/from the transceiver goes immediately low
upon key down and stays down after key up for a time?

The only immediate low on key down is from the key itself.
So,  I am leaving the -5 Key 1 jack "diode connected" to the
keyer output.  But,  after some thought I decided to go back
to the N.O. amp relay output jack on the back of the transceiver.
This is a line that must go low before RF comes from the
transceiver and stay low for a moment or so after RF stops;
it is the only output from the rig I could imagine would fit the
needed description of the "QSK line".  So I tried it.

I connected the Key 2 input jack of the -5 to the N.O. Relay
output jack on the back of the transceiver.....

Voila!!  Now  everything seems to work as it should.  The
fuse lamps do not flash.  I have gradually increased output
power up to about 300 watts and no sign of  problem!
Full rcv signal amplitude between CW elements using the
fast QSK setting on the Omni.  

But, I have left the AUX output from the  -5 open,  connected
to nothing.  Don't really see what the point of the direction
in fig 2a is to connect that jack over to the Key 1 line;  or
maybe it is a way to operate SSB,  but would have to find
somewhere else to connect the Key 1/AUX lines.  Figure
2a says to connect to the VOX relay.  Isn't that the same
N.O. relay jack to which I now have Key 2 connected?

Phil continued:

> Your 1000D has a hand-shake line, Jim. The line is on the band
> data jack, it is called "linear amp." It is normally grounded through
> a set of spring contacts built into the DIN plug installed into the band
> data jack. With this lead un-grounded, no RF will come out of the
> transceiver. You can still trip the VOX, key the amp, do QSK, but
> no RF comes out of the 1000D until you ground the line.This line
> is grounded last by the QSK-5 by hooking it to the "KEY 1" and AUX"
> jacks on the QSK-5, as shown in fig. 2a in the QSK-5 manual. My
> FT-ONE has the same thing. Maybe this will enlighten you on what
> "hand-shake" means.

Ok Phil,  well I seem to have this gadget playing with the Omni for
now,  hi.  Will stay with that,  then work my way over to this
connection you describe for the 1000D.  What you describe
sounds a bit similar to the TX OUT and TX EN jacks on the back
of the Omni,  but not really sure about that,  hi.  I was not able
to get them to help me a bit,  and tried them into Key 2 jumperd,
etc.  But,  if they are not jumpered,  as you describe with the FT,
no RF will leave the Omni,  hi.

Anyway,  a fairly lengthy struggle,  but with thoughts and comments
from many of you,  the end seems to be here!  Thank you all,  very
much!

73,  Jim  KH7M



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