z>Dumb question time: I know that most antennas function well on
z>the 3rd harmonic of their resonant frequency, but how would my
 > co-linear 5/8 wave 2M J-pole do on 70 CM?
Quite well, thank you.
But, first off - the only 'dumb' question, is the one you don't ask! ;-)
Same principal as how your 40m antenna allows for operation on 15m.  21Mc is 
the third harmonic of 7Mc.
z>Sounds interesting... with 12 stubs, somewhere around 13" for
z>each for 2M
z>makes around 13 Ft.  Do you have any idea about how many dB to
z>expect from
z>this, compared to a co-linear 5/8 J-pole, which is about 8 Ft
z>tall,
z>(6 dBd)?
No, actually... I know that the more elements you solder together, the more 
gain it has.  But, there's a point of "diminishing returns".  So, around 12ft 
to 15' ought to be about good enough for anyone.  I -think- it's around 12db 
or so.
-73 = Best Regards,
-Jeff KA5THB
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