Well you can't beat the price!
Is Electronics Exchange the type of place that would not mind if you bring along a 9 volt battery and make sure that the Calibrate setting registers 70db as per the manual?
http://www.farnell.com/datasheets/3824.pdf or is it a take it or leave it type of place?
The unit apperently (?) has only "A" weighting, period. Which I think is this? (somebody please correct me if this is wrong)
Frequency Curve A
Hz dB
16 -56.7
31.5 -39.4
63 -26.2
125 -16.1
250 - 8.6
500 - 3.2
1000 0.0
2000 1.2
4000 1.0
8000 - 1.1
16000 - 6.6
So unless one is doing OSHA measurements, it is basically a 500-8,000 Hz meter and can't measure bass without extrapolation and +/- 3db.
Not exactly a Bruel & Kjaer, but for $15 instead of a B&K at $1,500 or $7,500......
However, a meter that has the C weighting as well as the A, like the Radio Shack, might be a lot more useful
Frequency Curve C
Hz dB
16 - 8.5
31.5 - 3.0
63 - 0.8
125 - 0.2
250 0
500 0
1000 0
2000 - 0.2
4000 - 0.8
8000 - 3.0
16000 - 8.5
You can find the Chinese "7 range T22" for $21 w/shipping which claims +/- 2db w/ A and C weighting on Ebay.
Ken