Greetings. I have a Motorola Nucleus II Base station, and I'd like to put it
in the weak signal portion of the 902 ham band. I have seen a conversion to
make the transmitter play as an FM repeater transmitter around 927 MHz, and
that is simple enough, but 902 is out of the programmable operating range of
the unit. Real data, like schematics is scarce. Here is what I know:
Unit is based on the Quantar/Quantro platform. My unit has a 928 MHz rcvr in
it. The PA is a 300 watt unit with the following device layout:
Input to a "power module" without the usual black or ceramic cover. 2 active
devices, a 33P53 and a 33P54 transistor (not typical Motorola numbering.
Probably left off the beginning-- the 48-86 part) Then into a driver, a pair
of 33P71's. From there into a 3 way divider feeding three dual amplifier
sections, each amplifier containing a pair of 33P71 transistors (total of 12
33P71s as finals) then into a 3 way combiner, a ferrite isolator, harmonic
filter then to the output.
What I need to know is:
1) How can the TX and RX be made to work at 902, particularly any
programming info (plan on picking IF off and using rcvr as a converter)?
2) What kind of transistors are the ones used in the PA? Is there a
commercial (non-oem) replacement that has published data?
3) I am assuming amp is class C. Is it possible to re-bias these to operate
linear?
4) Is there any data available in form of schematice, etc?
5) Don't know enough about striplines to figure out how the two transistors
are combined in one amplifier. Looks like one is fed, then there is a
stripline trahsmission line of a specific length feeding the other. Outputs
are combined in a similar fashion.
It'd be great to get 300 watts on 902. SSB even better, but CW would be
acceptable. Don't plan on running FM at 902.
Or just maybe there is a repeater builder out there with nice a transverter
lying around ..... 902, 1296 or 2.4 Ghz
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