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the maths is not so simple, arctan i dont have it on my calculator :shock: so i found an online calculator and guessed how to do it while i wait for your reply on series matching even if this is not how you would do it,

using 27.205 mhz as the centre frequency,

7.12ft 107.4 degrees of 50 ohms coax in series with 3.25ft 48.99 degrees of 100 ohm coax both .66 vf to match a 17ohm purely resistive load to a 50 ohm transmitter, then you can feed this with any length of 50 ohm coax to get to the transmitter i think,
if 100 ohm is not available parallel 50 ohms could be used to make a 25ohm matching section then adjust the 50 ohm and 25 ohm lengths accordingly,

im half asleep but i had to have a guess once i realised you had posed a question

<blockquote data-quote="bob85" data-source="post: 81768" data-attributes="member: 18">the maths is not so simple, arctan i dont have it on my calculator :shock: so i found an online calculator and guessed how to do it while i wait for your reply on series matching even if this is not&nbsp; how you would do it,using 27.205 mhz as the centre frequency,7.12ft 107.4 degrees of 50 ohms coax in series with 3.25ft 48.99 degrees of 100 ohm coax both .66 vf to match a 17ohm purely resistive load to a 50 ohm transmitter, then you can feed this with any length of 50 ohm coax to get to the transmitter i think,if 100 ohm is not available parallel 50 ohms could be used to make a 25ohm matching section then adjust the 50 ohm and 25 ohm lengths accordingly,im half asleep but i had to have a guess once i realised you had posed a question<img src="https://cdn.jsdelivr.net/joypixels/assets/8.0/png/unicode/64/1f633.png" class="smilie smilie--emoji" loading="lazy" width="64" height="64" alt=":oops:" title="Oops!&nbsp; &nbsp; :oops:"&nbsp; data-smilie="10"data-shortname=":oops:" /></blockquote>

[QUOTE="bob85, post: 81768, member: 18"] the maths is not so simple, arctan i dont have it on my calculator :shock: so i found an online calculator and guessed how to do it while i wait for your reply on series matching even if this is not how you would do it, using 27.205 mhz as the centre frequency, 7.12ft 107.4 degrees of 50 ohms coax in series with 3.25ft 48.99 degrees of 100 ohm coax both .66 vf to match a 17ohm purely resistive load to a 50 ohm transmitter, then you can feed this with any length of 50 ohm coax to get to the transmitter i think, if 100 ohm is not available parallel 50 ohms could be used to make a 25ohm matching section then adjust the 50 ohm and 25 ohm lengths accordingly, im half asleep but i had to have a guess once i realised you had posed a question:oops: [/QUOTE]

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