Sunday, March 18, 2007

IQ RF Recording From Yesterday

Like I said in my previous post, I made a short (15 seconds) RF recording yesterday. Had a listen to it today. It is soooo cool to sit at home and tune around, change modes, bandwidths and display! I like it a lot. The picture shows a "Combo" (2D and Vertical Waterfall) display of the 100 kHz; I was tuned to JOIF Fukuoka 1413 khz when the screendump was taken.

I recorded audio from the RF recording with TotalRecorder. Went like a breeze, similar to making a recording from a usual receiver.


Walt Salmaniw said...

In the real world, how much hard disk space will it take to record a DX session. Let's say the full 190 kHz for 2 hours? That's the sort of thing I want to do. Doable? ...Walt

Bjarne Mjelde said...

190 kHz will consume roughly 47 MB per minute, or roughly 68 GB for 24 hours. Luckily for us, external storage has become quite cheap, and getting cheaper all the time. The average laptop HDD won't last long... I've thought of minimising storage problems by recording only around the TOH and BOH. Assuming of course that you have a "usual" receiver or two to tune around with the rest of the time.

Walt Salmaniw said...

Pretty reasonable. I can see a whole dxpedition with that amount or less, providing perhaps months of fun exploring the various frequencies. 21 or so 9 kHz channels possible here. Normally we'd be dxing 3 or 4 hours before and after dawn over several days. Quite possible to do, as long as time permits. I think a good 80 or 100 or more GB external HD makes the most amount of sense here.

Anonymous said...

OK guys,
I have now 3 x 250 GB, one internal 250 (only 150 yet there), one 150 GB & two laptops with a few GB... maybe more than 1 TB recordings of this season to analyze; mainly Far east & TA-stations from August up till now... Have to check the latest 2 TB RAID HDs for the next season !
73 tarmo

Bjarne Mjelde said...

Tarmo: Ever considered outsourcing???

4nradio said...

I recently saw a Western Digital 160 GB external 2.5" size USB hard drive for just $69.00 US. Now *that's* a good deal! My similar 120 GB Western Digital drive was bought a couple months ago at $99.

I think my SDR-1000 consumes somewhat more than 68 GB for 24 hours, even at its current 96 kHz bandwidth, but I'll have to check. When my Janus/Ozy board combination arrives from the HPSDR-TAPR group, then I'll be able to record 192 kHz of spectrum. What I'm *really* looking forward to is the HPSDR's "Mercury" receiver, that will likely be configured to be able to store 1+ MHz of bandwidth to disk.