User's Manual

9-32 68P81093C75-A

5. Slide the Exciter mounting plate out of the chassis with the IPA

module still attached.

6. Remove four Phillips screws from the corners of the IPA

module, and lift the module off of the Exciter mounting plate.

7. Set the new IPA module in place on the plate, making sure the

3-pin header is towards the rear of the station.

8. Slide the Exciter mounting plate back into the chassis,

reattaching the 3 cables removed in Step 4.

9. At this point, the station may be powered up while it is still out

of the case to make sure the new IPA module is functioning

properly. Unplug the station before continuing to the next step.

10. Reassemble the station by reversing Steps 2 and 3.

After Installing the

New IPA Module

Perform the following alignment procedures as described in the

Setup and Connections section of this manual:

• Power Output

Power Ampliﬁer

Frequency Band

Considerations

When replacing the Power Ampliﬁer, it is important to remember the

frequency-sensitive nature of the Exciter/Power Ampliﬁer

combination. The Exciter and the PA must match according to the

model breakdown table in this manual. If a PA with a new frequency

band is being installed, the corresponding Exciter must be installed,

as described in the Exciter subsection of “Module Replacement.”

Of equal importance, the PDR 3500 motherboard contains circuitry

which translates between the Exciter from the original Quantar and

the PA from the Spectra™ mobile radio. Since the translations

depend upon the frequency band of the Exciter and the PA, this

circuitry is also frequency-sensitive.

The DIP switches on the motherboard must be set according to the

frequency of the station in order for the proper translation path to be

selected. The DIP switch settings can remain intact if

• The band of the new PA matches the one being replaced, and

• The Exciter is not being changed.

If the PA band or the Exciter band is being changed, the DIP

switches must be conﬁgured to match the new frequency of the PA

and Exciter. Detach the motherboard from the chassis and set the

switches as described in the Backplane subsection of “Module

Replacement.”