tag:blogger.com,1999:blog-3380839830287420877.post4091060212401922949..comments2024-03-26T07:29:36.610-07:00Comments on VE7SL - Steve - Amateur Radio Blog: 630m Wilkinson Power CombinerSteve McDonaldhttp://www.blogger.com/profile/06229640265009249231noreply@blogger.comBlogger2125tag:blogger.com,1999:blog-3380839830287420877.post-91914215049782759722019-07-02T04:03:41.215-07:002019-07-02T04:03:41.215-07:00For future reference I built a 137kHz version of t...For future reference I built a 137kHz version of the combiner and found it did not work as expected combining two voltage mode Class D amps. I put it aside until my knowledge could be increased. I eventually found that my problem was combining two square wave outputs prior to the single LPF filter I had put AFTER the combiner. This narrow band type of combiner does not like all the harmonics in a square wave output and reflects them back to the amps, causing terrible drain waveforms. i built a second LPF exactly matching the first one I had built and put them BEFORE the combines so it was now combining clean sine waves without the harmonics and it worked perfectly! I would imagine using current mode amps thos problem does not occur. I hope this may help others, thanks for the great blog Steve!2E0ILYhttps://www.blogger.com/profile/14450120705963981202noreply@blogger.comtag:blogger.com,1999:blog-3380839830287420877.post-81470578205026486042014-09-24T04:27:01.868-07:002014-09-24T04:27:01.868-07:00Two Wilkinson splitter/combiner Rules-of-Thumb fro...Two Wilkinson splitter/combiner Rules-of-Thumb from the Microwaves101 dot com Encyclopedia (lots more Wilkinson stuff there):<br /><br />1. The isolation of a Wilkinson is limited to 6 dB better that the return loss of the source match at its common port.<br /><br />2. The split port return loss of a Wilkinson is no better than the return loss that is seen by the Wilkinson at its common port.<br /><br />Enjoy, David WB4ONA<br />Anonymousnoreply@blogger.com