Can the SPECTRAN V6 be used below 10MHz e.g. down to 9kHz or even 1Hz?
I know that the lower frequency limit is stated with 10MHz but i am wondering if the V6 can be used below 10MHz?
Yes this is possible, BUT:
- The default calibration is only valid down to 10MHz, so you might get wrong power readings below 10MHz. We offer an optional calibration down to 1MHz.
- The overall noise will raise the lower the frequency.
If you can live with those limitations you are free to give it a try.
Attached is a screenshot showing what will happen and what you will get.
The red MaxHold trace was a calibrated testsignal sweeping over the full frequency range at -40dBm. So the V6 is quite accurate untill around 6MHz and then starts to drop simply because no calibration was performed below 10MHz .
The yellow AVG trace shows the noisefloor which is rising the lower the frequency.
The example markers at 1MHz, 2MHz, 3MHz, 4MHz, 5MHz and 10MHz show this quite good.
After calibrating the lower frequency range you get the real picture as shown attached. We offer this additional calibration as an option:
Uploaded files:
Similar to Rx @ 9KHz (uncalibrated), do you allow the TRANSMIT o/p frequency to be set as low as 9 KHz?
I need to generate some ELF/HF signals and am willing to accept noise, level and frequency inaccuracies (I understand it will not be calibrated) if the SW setting allows selection of up to 9 KHz in the lower end.
No this is not supported so far.
My application is to simply record IQ stream. I believe this is not dependent on calibration. So, can i use V6 RTSA250/500 to capture IQ streams right upto 9 kHz, regardless of calibration?
Yes you can capture down to DC but as mentioned the sensitivity and image rejection is not specified and the sensitivity drops a lot (high NF).
Hi,
I'm not able to set the frequency lower than 5 MHz. Are there some special settings I need to set before I can adjust the range down to 9 kHz?
See https://v6-forum.aaronia.de/forum/topic/low-frequency/ and https://v6-forum.aaronia.de/forum/topic/full-sweep-mission-from-5mhz-to-6ghz/
You need to bypass the preselector within the SPECTRAN V6 PLUS block.
Thank you! Even with that mission I'm not able to get down to 9 kHz... what am I doing wrong?
Uploaded files:
When not using the automatic filter setting the minimum possible center frequency is defined as IQ Rate * 0.42 * SpanFactor. As by default the RTSA will drop slightly more than 8% of measurement data at the spectrum edges you will have to enable the "Full Spectrum" option to get near 0 Hz.
However with 92 MHz or lower IQ rates there seem to be some issues regarding the displayed frequency range on the V6 Plus. As can already be seen in your screenshot, the configured center frequency doesn't match the center of the displayed spectrum, which indicates that the displayed frequency values are incorrect.
Keep in mind that this isn't really a supported use case and the data in that very low frequency range can not be considered valid either way.
Thank you very much for the detailed explanation. I was noticing the issues regarding the displayed frequency range as well when I was playing around with it yesterday.
I know it is not supported but we are still waiting on our V6-eco order, so I thought I could do some indicative measurements with the V6 Plus... but I guess I have to wait 😉
