[TenTec] Looking backward? The search for the 'Holy Ham Grail!'

[Jerry Volpe]

"Looking backward...."

Speaking as a former RF engineer with an eye toward the future but a 
pocket book firmly planted in today..... and having invested in and 
subsequently divested myself from SDR technology for the moment... here 
are my thoughts/opinions:

If you want excellent bandpass characteristics with steep skirts and the 
best ultimate rejection outside the desired bandpass then analog 
filtering is still the best if not the only answer. When the day comes 
that DSP derived filters can operate at 45, 9 or even 6 MHz then the 
'new technology' will have great potential advantages. For now, if you 
want the benefits of up-front roofing bandpass optimization then you are 
simply must use analog.... even in the obsenely expensive new round of 
Jap radios.

Now as far as whether or not it makes sense to add additional 'poles' of 
crystal filtering in front of Ten-Tec's own up 9 MHz 1st filters, well 
that may be somewhat like the quest for the "Holy ham grail!' We simply 
can never get guaranteed single-signal reception in any mode under any 
conditions with today's technologies.... analog or digital.... but that 
doesn't mean we shouldn't see how close we can get to it. Trading in an 
Omni-V or VI for an Orion or an IC-7800 may move you slightly more in 
the 'grail's' direction but in my opinion at a rather significant 
re-investment for a rather insignificant move (ignoring comfort/wiz-bang 
features)... The Omni series transceivers are great performers. On the 
other hand, adding 8 or more poles of well designed filtering before 
existing filtering has the potential to make an equal or perhaps better 
shift towards that grail at a rather modest investment. Only time and 
testimonials will tell if INRAD's rootfing filter modification makes a 
genuine 'positive' difference that would be proportionally appreciated 
by most of us.... and of course there is always the question 'is my Omni 
really all that bad without one?'

Just some random thoughts on this very interesting subject in the weeee 
hours of the morning.

73,
Jerald, KG6TT


John Rippey wrote:

> Even as I am considering getting the new INRAD "roofing" filter setup 
> for my OMNI VI, I can't help wondering: doesn't this improvement 
> represent a step backward in terms of technology? Adding analog 
> filters on top of analog filters as a compensation for shortcomings in 
> various rigs seems to me to be an odd way of moving forward. But it 
> sure is cheaper than buying new technology :-)
>
> 73,
> John, W3ULS
>
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