How can a 150 MHz Tektronix TDS420 oscilloscope, with a spec of 100
MS/s, say that it's sampling at 10.0 GS/s?

In the last photo at the URL below, the display indicates that the
sample rate is "10.0 GS/s". How can that be?

I am selling this scope on Ebay. But it wasn't my personal scope and
I'm not very familiar with Tek's "newer" digitizing scopes. Is it
using some sort of averaging, to achieve a higher apparent sample
rate, or what?

For reference, here's a copy of the ad posted for the scope:

--------------------------------------------------------------

Tektronix TDS420 150 MHz Digitizing Oscilloscope, with 3 OPTIONS and 9
Manuals

**** Money-Back Right-of-Return ****

--------------------------------------------------------------

Gee whiz!!! It says it's sampling at 10.0 GIGA-SAMPLES PER SECOND, in
the photo at:

http://cgi.ebay.com/ws/eBayISAPI.dll...tem=2567576204

--------------------------------------------------------------

(For sale or auction Tektronix TDS420 150 MHz 4-Channel Digitizing
Oscilloscope with GPIB, with three OPTIONS (see below), and including
nine Tektronix user and service manuals.

**** INCLUDES THESE factory-installed OPTIONS **** :

Option 2F: Extended Waveform Math/DSP; FFT, Integration,
Differentiation.

Option 1M: 30,000 or 60,000 sample points per channel instead of the
standard 15,000.

Option 05: VideoTrigger; NTSC, PAL, HDTV, FlexFormat.

--------------------------------------------------------------

The TDS420 Digital Storage Oscilloscope features 150 MHz bandwidth,
100 MS/s sampling rate on 4 channels, 4 digitizers, a sensitivity of 1
mV to 10 V/div (with calibrated fine adjust) and 25 automatic
measurements.

--------------------------------------------------------------

This Tek TDS420 is in EXCELLENT working and cosmetic condition! (See
close-up photos, at the URL below.)

I have tested it and everything works exactly as it should.

This Tek TDS420 has no damage. It has only VERY MINOR signs of normal
use. And it is very clean. There are no bent, cracked, broken, dented,
missing or otherwise-damaged parts anywhere on this scope.

**** Money-Back Right of Return ****

Includes NINE Tektronix manuals.

--------------------------------------------------------------

For more details, photos, complete specifications, and to BUY IT NOW
or place a bid, just go to:

http://cgi.ebay.com/ws/eBayISAPI.dll...tem=2567576204

Hurry! Auction ends Oct 28th, 6:00 PM PST.

--------------------------------------------------------------