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Re: Norsat/Drake comparison



Hi Eddie.
I also have done some qualitative testing between these two downconverters (same mods) and can confirm your findings.  I could find no observable difference between then on MMDS, but noted the same as you, the Drake seemed to have a little more gain in my "testing."  Here's what I did... I set up my "duckling" on the other side of the house and then installed a piece of wire 1" long in the RF-input of the downconverter and observed the signal strength reading (S-meter) on my mobile rig at 145.500 MHz (corresponds to 2401.500 MHz).  The Drake was S8 while the Norsat was S7.  I then moved the duckling outside and kept moving it farther away until I could barely detect it on the Drake.  I could still hear it on the Norsat, so I have to agree with your assesment of weak-signal performance being comparable.

The Norsat is an easier unit to work on as the internals are more spread out and you don't have to fool with an LO shield.  Unlike the Drake, the stock unit's input is at ground (like the TSI 3733) and it has a -10 dB test port (like the CalAmp units).  
73,
Jerry, K5OE

wb4mle@mindspring.com writes:

> Norsat has xtal change and teflon tape mod. Drake has xtal change,
> i.f. mods (cut 2 coils,caps- add 22pf caps), filter lines extended and
> input hairpin modified.
> Drake no signal noise floor= S1. Beacon a min. of S3 at 2356Z.
> Norsat no signal noise floor= S0. Beacon a min of S2 at 2345Z. 
> Several swaps were consistent in the results. The Drake seems to have
> about 5db more gain than the Norsat. Anything heard on one could be
> heard on the other even with no S increase so the noise figures are
> close. 
> All above are on a 20 turn pvc pipe helix held up by a stepladder.
>     I hope David's Agilent ATF54143 project is successful and can
> be reproduced cheaply. This device or similar ahead of the Norsat will
> probably come as close to "Cheapsat" as you can get.
>     Too bad LEILA cannot chomp the station tuning on top of the
> beacon and way stronger than it.....
> -- 
> Eddie Seymour, WB4MLE
> E-Mail wb4mle@mindspring.com
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