P200 UHF Sensitivity

[ka1nvz]

Hello, I recently picked up a UHF P200. After programming to the some local area repeaters the sensitivity on all channels seems to be off. Is there internal tuning that can be done to the RF front end of the receiver?


Thanks

-Tom

[MTS2000des]

the UHF Genesis radios (P200/HT600/MT1000) only have a maximum separation on UHF of 6-8MHz on receive without losing performance. Assuming your radio was used on 460 or 450MHz, it will need a slight realignment to bring the two pole Butterworth filter to 440MHz. If you remove the face of the radio, you will see two tuning slugs visible from through the front shield. Usually turning the LOWER slug at about a 1/4 increments of a turn counterclockwise while receiving a weak signal (program in a distant active repeater if you don't have access to a sig-gen) in the center of the band will improve the sensitivity. I usually stagger tune mine for 455MHz as I use them on GMRS and ham, the performance usually hangs around .6uV at 443MHz and .5 at 462MHz which is good enough for repeater work. I have noticed that later production (1993) vintage HT600/MT1000's seem to be a little bit more broadbanded than earlier ones.

Of course if you know someone who can do a proper alignment that is recommended.