T/R Clicks

Output from J310 at junction of R23 & 24. Quite a lot of noise during transmit although QSK is off. Spike 3mS after T/R transition, coincident with 12R assertion. Effect appears completely idependent of code speed.

Output from AD603. 200mV p-p splurge commences coincident with assertion of 12R and rings for about 4mS. Effect appears completely independent of code speed.

Output at IC6b. 200mV p-p at 15kHz commencing at 12R and ringing to zero over 4mS. Independent of code speed.

Codec output. High amplitude crxp in the gap easily visible. Sounds clicky with 7.3=0, 7.4=0, 7.5=1

Codec output. Crxp in the gap reduced to <half amplitude with increase in 7.5 to 8.

Codec output with speed 31wpm and 7.5=8. R/T transition impinges on the crxp and click becomes pronounced

Codec output. Speed increased to 34wpm, 7.5=8 Crxp gone and click disappears.

Speed now 40wpm and suddenly some new crxp appears somewhat earlier in the gap. Click re-emerges.

52wpm and R/T transition now impinges on new disturbance and click increases in intensity. From 54-59 wpm there is no click.

Wooops! Here we are at 60wpm and another disturbance suddenly appears in the gap. Click returns.

What I'm struggling to understand is this...........................

The disturbance at J310 output appears unaffected by code speed.

The ringing output of the AD603 also appears unaffected by code speed.

The ringing output of IC6b is similarly unaffected.

All of the above effects are over and done with 7mS after a T/R status line transition. Why then, doesn't 8mS of 7.5 T>R blanking see off the effects of this stuff independent of code speed???????