[TenTec] din connector, etc.

[Jim Brown]

On Wed,9/24/2014 1:15 PM, Lee WA3FIY wrote:
> Ahhhhh....... where do you get that Jim?

Three good ways, depending on your resources. 1) RTFM for the product 
involved. 2) Hook up a dual trace scope so that one channel looks at the 
PTT line and the other looks at the RF waveform, then send dits and sync 
the scope to the PTT signal, and read the delay. 3) Download and study 
the ARRL Lab report for the product in question, which does a similar 
measurement.

I just looked at one of my K3s -- TX Delay can be set in 1 msec 
increments from 8 to 20 msec. 8 msec is the default.  The FT1000MP 
manuals went with the radios when I sold them, but I just looked at a 
summary of menu settings. It looks like the MP is variable from 0 to 30 
msec, with 5 msec being the default.  I looked at the ARRL lab test 
report for the TS850. One division on the scope trace is 20 msec, and 
the delay looks like about 8 msec.  I clearly remember that the K2 
provided a delay of 8 msec from an RCA connector on the back of the amp 
module, and I used it quite successfully to drive the PTT input of my 
Titan.

>   Various Ten-Tec, Elecraft, and Yaesu radios all
> have Rx to Tx turnaround times of at least 16mS (Eagle) to 36mS (FT5000) with other Ten-Tec's and Elecraft in between.

Go back and read that spec more carefully where you see it listed -- in 
the TS850 review, there's a spec for TX to RX turnaround, which is 
simply the hang time, and yes, it's about 17 msec. VERY different 
characteristic. What I'm calling "hang time" is how long the T/R relay 
stays in TX mode.

73, Jim K9YC