Topband: Topband Strange Propagation

Richard (Rick) Karlquist richard at karlquist.com
Sat Jan 16 22:49:07 EST 2016



On 1/16/2016 12:10 AM, Gary Smith wrote:

> There's an odd behavior that we've all heard & that's the "ditter",
> the person who on the DX frequency sends the occasional dit, not a
> string, just a dit & then some odd seconds later does it again. I
> wonder if they do it to bust the chops of someone like me who tries

> KA1J
>

Some auto tune linears are set up to change bands or sub-bands
by sending one dit.  With peak reading meters, they will also
display RF out and SWR from one dit.  At least this is a lot
less QRM than tuning up the old fashioned way.  In both
cases, the solution is to select SPLIT before transmitting
or just tuning.

Most rigs have IF gain this is optimized for phone, which
means it is way too low for CW.  This results in an AGC
threshold that is way above the rig's internal noise level.

Short of redesigning the rig (I actually did this to an FT-757
by adding an IF gain stage), you should use an audio attenuator
in front of your headphones so the the rig's audio output stage
clips before the level in 'phones gets too high.

Rick N6RK


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