The stock Motorola Mitrek UHF radio uses one (UHF type) RF connector for Tx-Rx functions. For repeater operation needs two separate ones. With the mounting of the radio on it's "side", now making the "front" it's best to place the RF connections to the "new" "right" side and leave the new "rear" clear for smaller enclosures. Plus, the hole for the old single connector is the correct size for the Tx port, plus, the hole for the 2135 key tumbler is also the correct size for the Rx port. The only problem is the sloping surface make it impossible to mount these connectors.

To solve this problem the front needs to be cut straight and thin enough for most RF connectors. As mentioned on the other page, you could remove the electronics to prevent metal contamination, or you could "seal" off them as discussed here. By using masking tape to completely cover the main board and using a recep saw carefully you can do this with a high probability of success. Out of the 12 radios modified by the Author only one was damage in a minor manner, but still usable. In addition this was due to impatience, where the cut was not complete and while breaking away the cut piece, torn into the Rx port area somewhat.

The big cut

Start with sealing up the main board with masking. Place the radio in a vice, using the radio's heat sink, as not to damage the circuit board..

 

 

 

 

 

 

 

 

 

 

 

Make the top cut, just under the lip of the radio.

 

 

 

 

 

 

 

Then make the other cut starting with the blade up against the outside part of the little gasket "trench" of the edge. Blade placement is important to produce the correct metal thickness for the connectors.

 

 

 

 

 

 

 

Next pry up the cut part; it will break away at the proper spot. Now shows the rough cut.

 

 

 

 

 

 

 

 

 

 

This will appear messy, but once cleaned up with make the proper mount for the connectors.

 

 

 

 

 

 

 

Use a spray bottle with alcohol and a high pressured air nozzle to wash away the aluminum shavings. Then you can peel off the masking tape. Then clean or check for any debris. You are ready to continue with the modifications discussed on the other pages, now.

 

 

 

 

 

 

 

Be sure to make a full cut before you pry away the scrap section. If you are impatient you'll break away the mounting area for the connectors as shown. In this case the radio will still hold them, just that the area would be weakened.

 

 

 

 

 

 

 

 

This may be copied or printed in complete form only for non-profit purposes, such as for the knowledge for the Amateur Radio Service, with AK2O credited as designer. Other arrangements please contact the author.

Copy write: AK2O 2007

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