Technical data

Service Guide 85309-90082 2-7
LO/IF Distribution Unit Operating Information
85309B 85309B Rear Panel Features
J7 and J8 (Using Non-Diplexed Mixers). J7 and J8 allow you to use a non-diplexed test mixer (a mixer that
has separate connections for the LO and IF signal). This is done by removing the Type-N jumper that
normally connects J7 and J8. With the jumper removed, make the following connections to your test mixer:
If you are using a test mixer that uses a single LO/IF connection and a diplexer, always place the supplied
Type-N jumper between J7 and J8.
J15 HIGH/LOW BAND SELECT (option 40x). Allows external control of the HIGH/LOW BAND SELECT
feature when the front panel BAND SELECTION knob is in the EXT position. See “BAND SELECTION (Option
40x Only)” on page 2-4. TTL high (+5 V) selects HIGH band; TTL low (0 V) selects LOW band.
Available Fuses
• Fuse (5 A/250V, 2110-0709) U.L. listed and CSA certified
WARNING For continued protection against fire hazard replace line fuse only with same type and
rating: Fuse 5A/250V, Part Number 2110-0709.
The use of other fuses or material is prohibited.
Figure 2-5 Line Fuse
Table 2-1 Connections for Non-Diplexed Mixers
85309B Connector Connection
J3 TEST LO/IF Mixer LO INPUT
J7 TEST IF IN Mixer IF OUTPUT
J8 DIPLEXER IF OUT
50-ohm Load
a
a. It is recommended that you place a 50-ohm load on this connector.