[TenTec] Corsair II noise blanker

[Rick - DJ0IP / NJ0IP]

* Why anyone would change a good design is a mystery. *

The requirements changed.

When the Triton was designed, about the only need for a noise blanker was
for ignition noise.
The noise blanker was often optional because if you didn't work mobile, you
didn't need it.

About the same time, The Woodpecker (terrestrial radar) hit the bands and
was a huge disturbance.
Manufacturers began modifying the NBs in an attempt to fight that
disturbance.
Some helped a little, some helped a lot.

Then rigs changed technology.
Radios with upward conversion were totally different and that required a
fundamental re-design, including the NB.
Now most radios are back to downward conversion.
Requires another re-design.

If we had always only had radios with just one single conversion and all on
9 MHz, then your question would certainly be a good one.  But things have
changed many times since then.

It seems that recently software NBs were tried but didn't work so well.
With the Eagle they have returned to a hardware NB and it seems to be
better.

When judging these NBs, you have to be careful.
In the presence of very short pulses, most DSP radios 'had' huge AGC
problems.
These are things like static crashes or electrical fences.
Flex and Elecraft successfully addressed this but others did not.
If you turned on an NB and find you still have problems, it may very well
have been that the problem was in the AGC and the NB doesn't help.  However
that has finally been improved (for OR and OM7) in recent firmware releases.

73 - Rick, DJ0IP
(Nr. Frankfurt am Main)

-----Original Message-----
From: TenTec [mailto:tentec-bounces at contesting.com] On Behalf Of Doug Reid

Why anyone would change a good design is a mystery.