Tektronix Webcam 070-8030-01 User Manual

Installation

1780R-Series Service Manual

Responses from the 1780R-Series SERIAL interface are shown in Table 2–7.

A

The transmission was successful (ACK)

C

Command not known. (The # character was received, but was not followed by a
U, u, D, d, P, or p.)

D

Bad data received (all expected data consists of ASCII printable characters).

H

Bad internal checksum.

N

Bad transmission checksum (NACK)

T

Timed out (the process took too long to complete).

V

Software version number mismatch.

The rear-panel XY INPUT connector is a 15-pin, sub-miniature, D-type
connector that provides input to the Horizontal and Vertical (X and Y) Amplifi-
ers. They are balanced (differential), DC-coupled, high impedance (>20 k

W),

un-terminated inputs provided for audio applications. If AC coupling is desired,
external capacitors are required. These inputs are factory calibrated for 0 dBm in
600 

W but can be adjusted for any 600 W system between 0 and 12 dBm. See

Figure. 2–7.

0 dBm is equal to 1 mW or 2.19 V peak-to-peak in 600 

W. 

12 dBm is equal to 15.8 mW or 8.72 V peak-to-peak in 600 

W.

To calibrate the 1780R-Series for a system other than 0 dBm, perform step 38 of
the Adjustment Procedure (Section 6) using a 1 kHz sine wave of the appropriate
amplitude.

Inputs can be driven single-ended by driving either the + or – X and Y inputs
with the opposite polarity inputs grounded.

In addition, a single-ended, high-gain mode can be used for other, primarily
non-audio, applications. It can be accessed by installing plug jumpers on J108
and J205 (on the Vectorscope board, see Table 2–5) and inputting the signal on
the +X and +Y inputs with the –X and –Y inputs grounded.