[RFI] Ultrasonic Dish

[Hisashi T Fujinaka]

On Wed, 2 Jan 2013, Lee K7TJR wrote:

>> Obviously receiver sensitivity is another important factor. I bought
> the Midnight Science RX2 and was not happy. The new RX3 is much more
> sensitive. I have no idea how it compares with the expensive
> commercial units. I bought all the parts to build the W1TRC
> receiver, intending to compare it with my RX3 on the test range, but
> simply haven't had time and energy to do it (yet). I wish I could
> get my hands on a Radar Engineers 250 for side by side comparison on
>> the range, but that seems highly unlikely.
>
>   I have had the chance to compare my snow sled dish versus the
> ARRL dish versus the Radar Engineers dish. There is NO comparison.
> I was able to get right down to the very arcing bolt with the Radar
> unit and only able to hear that arcing was present with either of the
> other two. This was from about 40 feet away from a bolt on the
> cross arms of a pole.
>   Paul and others are right, it is about dish and dish illumination
> accuracy to get the best from an ultrasonic dish. As with most
> receiving systems, gain is easy to get and narrow beam patterns take
> accuracy.

I'm just looking to tell WHICH POLE is arcing. I can't do much about it
and the power company in my area is going to re-check my findings
anyway. I think one of the issues with people trying to find exact
parabolic reflectors vs something "good enough" is what sort of
resolution they're looking for.

Once I can determine which pole it is, can I see the arcing through
binoculars? I don't remember if anyones discussed that.

-- 
Hisashi T Fujinaka - htodd at twofifty.com
BSEE(6/86) + BSChem(3/95) + BAEnglish(8/95) + MSCS(8/03) + $2.50 = latte