Never mind!  Googled it and found between 200 and 600 ohms.  Either 
Shure should work fine.  Something I want to try here as well.
Pat, K9JAUAt 02:45 PM 11/14/2015, you wrote:
>Steve:
>
>Your right. From classic old tubed radios to mics. I suppose its like an
>owner of a beloved 1957 chev that need to be kept running in top condition
>no matter the cost. LOL
>Well the cable is made up for my Yaesu mic to be boom mounted and your not
>the only 1 who said I sound the best on that one. NC4L the 102 guy in FLA
>told me to throw the heil in the trash. LOL He likes the Yaesu mic,
>probably because its accessoried matched to the radio.
>I should be out to the cottage the next 2 weekends in a row, will try the
>40M round table and maybe a 75M sched. A wind storm blew in last week and
>decided to put my antenna down rather than bother my XYL to help me at 2 or
>3 in the morning if the wind got to high.
>Hope to catch ya on the air next week.
>
>73:
>Mike DE VO1AX
>
>
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