Hi,

This Description misses some important things.

Thie mixer IF port is used as input. If you select the right mixer the input can be DC coupled, allowing measurement down to very low frequencies.

Also it can make sense to use a higher IF then 10MHz for easy filter implementation.

To have a good level translation use a 3dB attenuator on all thee ports.

Mini Circuits high level mixers work great for this purpose.

All the Best,

Isidro

herunterladen

Am 21. Dez. 2022, um 16:14, "Kenneth Greenough via " <talktalk.net@groups.io target=_blank>[email protected]> schrieb:

Hello Larry,
An up converter is basically a mixer,double balanced being best for the
purpose and an oscillator.? For stability the oscillator will likely be
a crystal controlled one.? Say the osc' is on 10 MHz and fed into one
port of the mixer, low frequency signals you wish to monitor are fed
into the signal input of the mixer. The output of the mixer is the
10 MHz osc, very reduced due to the cancellation balance of the
mixer and the low frequency signals appear as modulation [ both
sidebands] of the 10 MHz. If you feed the output to the SA you can
monitor the modulation. in other words you have up converted the
low frequency signals.?? A down converter works in exactly the same
way to monitor higher frequencies which are above the upper limit of the SA.
?Ken g8beq?

On 21/12/2022 14:14, Lawrance A. Schneider wrote:

If ignorance were bliss, I'd be in heaven. ?I'm not there yet but I am ignorant.

What is an 'up converter'? ?Yes, I understand the words but that does not tell me what it is nor how it works.

Thanks, ? ? ? ? ? larry