John,
You should be able to get 100 watts or better... but it won't last
very long. Per Motorola's spec sheet the UHF mobile is rated at 35
watts maximum for continuos duty which is what a repeater does. The
same ceramic PA sections are used in the Compa-Station but they are
mounted on a heat sink that has one fifth the thermal resistance and
they derate it to 75 watts output . Even at 35 watts out you will
need fans on the outside heat sink and blowing right on the ceramic
substrates. Micor PA's are well known for un-soldering their parts
and generally not real reliable. You would be better off to
totally bypass the four final PA transistors and use just the 45 watt
PA driver stage. It will draw much less current and generate less
heat with just the driver as compared to running the final PA at 45
watts. My thirty-two year old Micor mobile that was converted to a
repeater twenty years ago was happy running 35 watts with fans until
a recent lightning hit. It's repairable but I decided it had a good
life replaced it with something more modern. So once again I'm
running hardware that some else though was junk.
Bruce WB6ARE
On Aug 16, 2005, at 7:18 PM, John wrote:
> Hello group. I have just duplexed a 100 watt 450-470 Micor Mobile.
> Next I installed the crystal for 447.95 RX, with high side
> injection to
> give me 442.95 TX. The radio is now tuned up on frequency, but I am
> only getting about 65 watts output, max, at about 20 amps of current.
> I have double checked everything; LLA output OK, tried a 2nd re-tuned
> circulator, tried driving the radio with a signal generator connected
> to the RX injection cable (to be sure that I was really tuned to the
> right harmonic). Everything seems OK, so my question is how much
> power
> should you be able to get out of a 100 watt Micor on 442.95 Mhz??
> Thanks for any info you can give.
>
> 73, John, k9KA
>
>
>
>
>
>
>
>
>
> Yahoo! Groups Links
>
>
>
>
>
>
>
>
Yahoo! Groups Links
<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/Repeater-Builder/
<*> To unsubscribe from this group, send an email to:
[EMAIL PROTECTED]
<*> Your use of Yahoo! Groups is subject to:
http://docs.yahoo.com/info/terms/
