Table of Contents
Advertisement
..
..
;.'/~;~:}~~~/-'
CHANNELSELECTION
5.
CHANNEL SELECTION
•' ..
t:,_:,;:,:~~,~ _
VSB-70's are shipped with two local oscillator crystals installed. The crystals
will provide operation at 434.00 MHz (F1) and 439.25 (F2) with channel 3
enabled for receiving and monitoring tra,nsmissions. You may be in a service area
that requires selecting the other channel. If you have a local TV channel 3 or 4,
choose the unused channel. You must install the correct crystal and set the unit
to operate on the selected channel. The following procedures and table provide
the information you need to change the channel seiection ..
Crystals must be selected from the table below for the desired channel and
operational frequency. to change from channel 3 to 4 or vice versa, contact AEA,
Inc., to order the crystals you need.
VSB-70 MIXING CRYSTALS
INOTE!
NOTE!]
If you install or change any crystals, you must perform the CRYSTAL INSTAL-
LATION PROCEDURE
below.
TRANSMIT FREQUENCY (MHzl
CHANNEL 3 (MHzl/AEAoart#
CHANNEL 4 (MHzl/AEAoart#
90.00/090-890.00
88.50/090-888.50
..
91.25/090-891.25
89.75/090-889.75
,
93.1875/ 090-893.18
91.6875/090-891.68
94.500/090-894.50
93.000/090-893.00
The above crystals can be ordered direct from AEA or through your 19.cal
dealer. Suggested price: $15 each.
The selection of channel 3 or 4 for display on your television receiver is deter-
mined by the position of a jumper on the circuit board inside the VSB-70. To
change the current channel selection of your VSB-70, perform the following:
1. Remove the power cord and the cover from VSB-70 ..
2.
Refer to page 12 to locate jumper JP2.
3.
Install JP2 to connect the center post to either "3" or "4" for the channel
desired.
4.
Perform the crystal installation procedure below.
CRYSTAL INSTAllATION
PROCEDURE
Equipment required for tuning: Bird or PEP wattmeter (1 watt), .075 inch non-
metallic tuning tool, desired crystal.
Do not adjust any inductors or variable capacitors other than the ones
referred to in this manual's tuning procedures (this page and page 10) as the cir~
cuits are factory tuned.
The VSB-70 is delivered with F1
=
434 MHz and F2
=
439.25 MHz as the
transmit/receive
operational frequencies. The unit is configured for either channel
3 or 4. Check the outside of the box to check which channel your VSB-70 is con-
6
Advertisement
Table of Contents
