### Help understanding use of "Upconverter"

Posted:

**Mon Oct 12, 2020 10:23 am**Hi all,

I would be grateful if somebody could explain how to correctly use an upconverter. I am relatively new to SDR but I have a reasonable understanding of radio frequencies etc.

My setup is as follows:

Hardware: NooElec NESDR SMArTee v2 dongle + NooElec Ham It Up Plus HF Upconverter

Software: SDR#

According to the technical documentation, the SMArTee dongle works for frequencies in the range 25 MHz to 1750 MHz (so for frequencies outside that range, an upconverter is required).

The documentation for the upconverter states it has a frequency capability of 300 Hz - 65 MHz in “upconvert mode” and 300 Hz to 6 GHz in “passthrough mode”.

If my understanding is correct, passthrough mode effectively means bypassing the upconverter which means the SDR software is using the SDR dongle only (I could be wrong!).

I have tried to represent this graphically in the attachment. I do understand the need to use the “Shift” value in SDR# when using an upconverter but I don’t understand when I should and shouldn’t use upconvert vs. passthrough modes.

If my understanding of the technical documentation is correct, if I use the upconverter in passthrough mode, I should be able to receive signals between 300 Hz and 6 GHz but that doesn’t make sense to me – if I’m bypassing the upconverter by using passthrough mode then I should only be able to receive signals between 25 and 1750 MHz i.e. the frequency range of the dongle.

I hope I’ve described my question clearly. Any help would be greatly appreciated!

I would be grateful if somebody could explain how to correctly use an upconverter. I am relatively new to SDR but I have a reasonable understanding of radio frequencies etc.

My setup is as follows:

Hardware: NooElec NESDR SMArTee v2 dongle + NooElec Ham It Up Plus HF Upconverter

Software: SDR#

According to the technical documentation, the SMArTee dongle works for frequencies in the range 25 MHz to 1750 MHz (so for frequencies outside that range, an upconverter is required).

The documentation for the upconverter states it has a frequency capability of 300 Hz - 65 MHz in “upconvert mode” and 300 Hz to 6 GHz in “passthrough mode”.

If my understanding is correct, passthrough mode effectively means bypassing the upconverter which means the SDR software is using the SDR dongle only (I could be wrong!).

I have tried to represent this graphically in the attachment. I do understand the need to use the “Shift” value in SDR# when using an upconverter but I don’t understand when I should and shouldn’t use upconvert vs. passthrough modes.

If my understanding of the technical documentation is correct, if I use the upconverter in passthrough mode, I should be able to receive signals between 300 Hz and 6 GHz but that doesn’t make sense to me – if I’m bypassing the upconverter by using passthrough mode then I should only be able to receive signals between 25 and 1750 MHz i.e. the frequency range of the dongle.

I hope I’ve described my question clearly. Any help would be greatly appreciated!