Mitrek High Split to 6M Ham Band Conversion        11-02-03

By Tom Herman, CETma   N1BEC/7

Here are the parts that need to be changed out to make the low band-high 
split Motorola Mitrek operate well on the Six Meter Ham Band.

The criteria here was to make the conversion as easy as possible, and to do 
this by changing out capacitors only, and just as many as are actually needed 
for good operation.

Possibly other parts could be changed out, but the following list will get 
you the best performance for the least grief!

Do yourself a favor, and use a good, hot soldering iron. To do this 
conversion, a number of  coil shields must be removed, and some of the 
parts are soldered onto fairly substantial groundplanes.

Also, if you do not solder the cans back on well, you will wind up with 
annoying intermittents!

After re-tuning, the Mitrek in question gave me the rated power of 50 
watts, and good receiver sensitivity.

Transmitter:

Part #        Orig. Value     6M Value    Notes:

C 701         16 pF               12 pF     Watch soldering on cans of L 701- 
C 703         24 pF               20 pF     L 705: Very Hi Q circuits! Poor 
C 704        150 pF              120 pF     Soldering will cause erratic TX 
C 707         33 pF               24 pF     power!
C 710         22 pF               15 pF
C 712         22 pF               15 pF
C 713         27 pF               20 pF


Receiver:

Part #        Orig. Value     6M Value    Notes:  

C 166          100 pF           80-90 pF    Rx picked up 0.05 uV sens. Tunes
C 101          30 pF             15 pF      much better after conversion!
C 104          22 pF             15 pF
C 106          22 pF             15 pF
C 108          22 pF             15 pF
C 110          22 pF             15 pF

Good Luck and have fun!

-Tom N1BEC