[TenTec] ORION Hi/Lo Cut control

[Bob Henderson]

I realise this topic has been aired previously but I am not sure it was 
satisfactorily concluded and I am not one who will readily let sleeping 
dogs lie!

For the most part I use the BW/PBT controls on my Orion.  They operate 
both logically and correctly, so far as I can tell.  On the other hand, 
I find operation of the Hi/Lo cut controls to be neither logical nor 
correct.

I have the following obsevations concerning operation of hi/lo cut and 
will be interested to learn the views of other users..

1.  Hi and Lo cut on the Orion refer to absolute frequency, which I 
suppose is technically correct but this has the effect of interchanging 
the audible effect of the controls when changing from USB to LSB.  I 
feel operation might be more logical or at least more intuitively 
correct if the terms referred instead to recovered AF frequencies.  In 
this way application of Hi cut would always reduce the HF part of the 
recovered bandwidth and likewise Lo cut would reduce the bass frequencies..

I made the following obsevations with the rig on USB.  As Hi and Lo 
currently relate to absolute frequency the senses would be reversed on LSB.

2.  The graphical representation of Hi cut appears correct.  The skirt 
furthest from the carrier is adjusted whilst the skirt nearest the 
carrier remains anchored.  However, adjustment of Hi cut does not adjust 
actual i/f b/w, until the Hi/Lo cut control is pressed and held for a 
second or so.  This makes no sense.  Actual b/w adjustment should be 
immediate while pressing and holding the control should reasonably 
restore the pre-adjustment b/w.

3.  The graphical representation of Lo cut is incorrect.  What should be 
seen, is movement of the filter skirt closest to the carrier while the 
skirt away from the carrier remains anchored.  The graphic shows both 
skirts being adjusted but at different rates.  This is not correct.  The 
numerical indication shows PBT shifting at twice the rate of b/w 
change.  This makes no sense.  What should reasonably happen would be 
for PBT to display a figure equal to the delta in b/w. The adjustment of 
the Lo cut control does however, adjust actual b/w immediately, unlike 
Hi cut and pressing and holding the control does restore the 
pre-adjustment b/w.

Incidentally, I have two Orions and my obsevations hold good for both of 
them.  They have also held good over a number of firmware releases, so 
this is not a new problem.

Whatsay?

73 de Bob, 5B4AGN