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stealthJamal
03-26-2005, 02:43 AM
I think Jim might know the answer to this.

What is the difference between the following two radar receivers?

Superheterodyne, GaAs FET VCO

Superheterodyne, Varactor-Tuned VCO


Thanks.

BiGeAsYgUy
03-26-2005, 03:01 AM
http://img65.exs.cx/img65/4536/369a6sl.jpg

This is the information for the original Passport (late 80's?-early 90's?) from Cincinnati Microwave that detected only X and K band. Check out the type of antenna it uses, sound familiar?

jimbonzzz
03-26-2005, 08:06 AM
I think Jim might know the answer to this.

What is the difference between the following two radar receivers?

Superheterodyne, GaAs FET VCO

Superheterodyne, Varactor-Tuned VCO


Thanks.

One oscillator uses a varactor, one uses a GaAs FET :D But seriously:

Superheterodyne, Varactor-Tuned VCO
This kind "tunes" the local oscillator by varying the voltage applied to a varactor diode...these have been around for a long time in TV tuners, and commercial gunnplexers have them for tuning/modulation...

Superheterodyne, GaAs FET VCO
This one, I don't know for sure...
Probably newer technology though. I was under the impression that newer detectors used DROs instead of gunn microwave sources, DROs are more stable but put out less power. I guess a DRO using a GaAs FET would qualify as a "GaAs FET VCO"...

The "Superheterodyne" part basically means that it uses the LO to mix the signals down to a freq that can be handled more easily...

Jim

stealthJamal
03-26-2005, 08:39 AM
just wondering because the Bel RX65 and the Original 8500 have:
Superheterodyne, GaAs FET VCO

The X50 has:
Superheterodyne, Varactor-Tuned VCO

CactusMan
03-26-2005, 10:41 AM
What type of receiver does the V1 have?

nvr2fast
03-26-2005, 12:22 PM
just wondering because the Bel RX65 and the Original 8500 have:
Superheterodyne, GaAs FET VCO

The X50 has:
Superheterodyne, Varactor-Tuned VCO

That is very strange... i thought everyone said that the X50 and RX65 share the SAME hardware platform (or 99.999% the same)? It sounds like they use completely different hardware actually?