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Old 8th Sep 2019, 9:18 pm   #20
G3VKM_Roger
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Join Date: Jun 2012
Location: Southeast Norfolk, UK.
Posts: 773
Default Re: Ex marine AM radio equipment.

Quote:
Originally Posted by G4_Pete View Post
Hi Bumped this back up as I forgot to mention the following and did not see it in the thread , apologies if I missed someones post covering this.

Converting to a PI output at 50 Ohms also enables an RF safety choke to be fitted to ground at the low impedance 50 Ohm end. These sets can run with an unrevealed HT coupling capacitor short and present RF+HT on the antenna.


Pete
A good safety point Pete. I've come across amateur equipment with that hazard, in fact the Harvey-Wells TBS-50 transmitter I use as an avatar photo on this forum has a 0.01uF cap between the PA HT and the aerial terminal. If that fails with a short circuit then the HT can get onto the aerial!

73

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