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Re: Topband: W8JI FT1000MP MKV Click Modification

To: "Guy Olinger, K2AV" <olinger@bellsouth.net>,<topband@contesting.com>
Subject: Re: Topband: W8JI FT1000MP MKV Click Modification
From: "Michael Tope" <W4EF@dellroy.com>
Date: Sun, 23 Oct 2005 18:40:33 -0700
List-post: <mailto:topband@contesting.com>
---- Original Message ----- 
From: "Guy Olinger, K2AV" <olinger@bellsouth.net>
 
> There are some missing details in your description so I don't know 
> your exact setup.
> 
> If you are listening on another RX and putting the audio to a scope or 
> a sound card and a scope program, do NOT use AGC on the listening 
> device. Turn it off and reduce the manual gain so that the RX is 
> running fixed RF gain.
> 
> If you are looking at the output of an amplifier and using ALC to set 
> the drive levels, then turn the ALC off. Reduce power manually to get 
> proper drive levels. Using ALC with a low drive amp will produce the 
> same affect as the AGC in a RX.

> If none of the above, remember that the MP uses some number of 
> physical relays (vs pin diodes) in the transition from RX to TX.
> 
> Use the menu setting 7-4 to introduce a delay of 4 or 5 ms (or more?) 
> to delay the onset of CW until after the circuits complete state 
> change.

The oscilloscope I used was measuring the RF envelope directly (I 
had a cascade of high-power RF attenuators between the output 
of the FT1K MKV and the oscilloscope input). The scope was being 
triggered by output of the AEA Morsemaster keyer that I was using 
to key the rig. I also listened to the FT1K MKV output on 2 different 
receivers (TS950SDX and Omni 6+) using a step attenuator to knock
the signal down to a nominal RX level (~S9+20). 

I was running the FT1K MKV barefoot at the full 200 watts (max 
exciter output). BTW, there is no separate drive control on the MKV 
as there is on the FT1000D - only a RF level control. 
  
I haven't messed with the delay settings in the menus. What I did do, 
was to manually close the T/R relay ahead of time using the "MOX" 
switch. This made NO difference. The leading character still showed 
a hard-edge even when I closed the relays ahead of time with the 
"MOX" switch. 

FWIW, I tested the TS-950SDX before I returned it to the local 
club station where I operate. The TS-950SDX did NOT show any 
edge change between mid-word characters and leading edge 
characters. It did show an extra 9 millisecond delay on leading edge 
characters as if the whole RF envelope was offset by 9 
milliseconds relative to the key closure, but there was no discernable 
modifications to the shape of the rising edge of the envelope. The rise 
time on the TS-950SDX is relatively fast (~1.5ms), but the contour 
of the rising edge is very smooth (like an S-curve) with no sharp 
corners. When I have listened to it in the past on another receiver, 
the keying on the TS-950SDX sounded a little on the hard side, but 
the radio didn't click noticeably. 

I play with the delay menu settings on the FT1K MKV to see if that
makes any difference. 

Thanks and  73,

Mike, W4EF...........



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