Brymen vs Scope measurement discrepancy

[Crossphased]

Hi,
I was setting up a recently acquired audio amplifier, to characterize the amplifier, when I ran into a measurement discrepancy between my BM521 and my Tek 2465A.  I'm using a brand new Siglent 2042X function generator to provide the waveform. The function generator is supposed to maintain the selected peak to peak voltage across different loads. That is, I believe the FG is able to modify its output impedance to maintain the selected VPP.

I started with 1VPP selected on the SG2042X, @ 1khz. The Brymen measure this to be .356 V but cant pick up the frequency:
https://farm5.staticflickr.com/4464/24316879128_bd4e9a3b52.jpg

I am aware we are comparing peak to peak voltage to RMS, but 1 VPP computes to .707 VRMS, not .356 VRMS. (curiously a division by two)

If the peak to peak voltage is raised to 2, the Brymen measures .711 VRMS and is able to pick up the frequency:
https://farm5.staticflickr.com/4532/37459341474_2a1c887b7c.jpg

.711 VRMS measured,  the value should be 1.414 VRMS for a peak to peak voltage of 2. Again, this is a factor of 2 error (.711 vs 1.414)

When VPP is raised to 3, BM521 measures 1.064 VRMS:
https://farm5.staticflickr.com/4469/24316879438_1385a92402.jpg

1.064 VRMS measured, the value should be 2.12 VRMS for 3 VPP. And again there is a factor of 2 discrepancy.

At this point I was baffled and hooked up the FG to my Tek2465 scope to see what was going on. I am using 10X probes, so the the display on the scope should be multiplied by 10. Sure enough, at 3 VPP selected on the FG I measure ~3 VPP out (3.12 V using cursors):
https://farm5.staticflickr.com/4461/24316879008_c9f0f29132.jpg

At this point I'm not sure if I'm making a silly logical error, or there is something amiss with the Brymen. I know I'm using a frequency of 1Khz but the same result was witnessed for 100 hz, 200hz, etc. Does anybody have any idea what's going on?

P.S. - having trouble embedding these images if anybody has a tip let me know

[barry14]

There is nothing wrong with either the DMM or the scope.  You are using the wrong factor to convert volts peak-to-peak to volts RMS.   For a sine wave, you need to divide the volts peak-to-peak by 2.828.  That is, 3 volts p-p is equal to 1.06 volts RMS (again only for a sine wave).

[Crossphased]

Hey Barry,

Thanks, I was being a bonehead lol. After your reply I realized my mistake.

The voltage for a single peak (upper half of sine wave) = 1.414*VRMS
The Peak to Peak is obviously double this.

Thanks for being sharp!