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Finally got my Rigol DSA815-TG

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Hi everyone!

Finally got my Rigol DSA815-TG. Let me just add that I was broke before I purchased it and even "broker" afterwards. Was going to get a Rigol DSA705, but decided I was better off to buy the 815 because it would be cheaper to buy that unit instead of later purchasing a separate tracking generator, etc...

So, I did the proverbial 250uV at 3m with a 1m antenna test. I saw something regarding a half wave dipole being used however went with the 1m because I seem to recall that being the one required. My equipment under test (EUT) was a C. Crane FM2 I purchased two years ago. At first, I was going to test the EUT by taking the spectrum analyzer to the transmitter. Then I realized it would be easier to take the EUT to the test equipment.

I had to move things around to have a place for the antenna that was 9' 10" away from where I was adjusting the FM2. Set up was:

Antenna -> cable -> 75 ohm to 50 ohm pad -> cable -> spectrum analyzer

I calculated an antenna factor for the dipole of 7.486 at 93.5 FM. To this I added the loss for the cables, etcetra for a total of 14.494. My goal was to adjust the pot in the EUT to 33 dbuV so that I could have a total measurement of 48 dbuV; AF+Loss+Reading.

Something I didn't realize until right before I got the SA is there is a difference between dbuV/m and uV/m. Fortunately I found the formula uv/m=10 to the power of (dbuv/m divided by 20). The lab that originally tested the FM2 for compliance used 48 dbuV as their limit. I did the same.

I've got other transmitter I'd like to bring to compliance. Been thinking of contacting the FCC to see what they would think about me taking on such a project.

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