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399, what is this on my 138XLR?


L_B -

I have never seen an 858 chassis with a transformer like that. Maybe for a power supply to run it as a base. Is there a number on the top of the xmfr?? also where is it connected to the radio. Hard to tell from the photos.

- 399
 
One wire goes fr tht + post of the power plug. Then from the other side of the transformer to where the choke usually goes to the board. Appears factory with all the brackets and screws that support it. But probably not then.
 

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The transformer is there to act as a large filter choke to help reduce alternator/RF noise across the 12V input from the battery, since the radio is a mobile. All 138XLR's have that choke. If the other 138 doesn't have that choke, it has likely been removed by someone. People have been known to remove these filter chokes in an effort to gain more TX output.

Hope this helps.


~Cheers~
 

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