Return to KLUBNL.PL main page
| To: | DK7FC <[email protected]> |
|---|---|
| Subject: | Re: LF: Varistor spike management |
| From: | Chris Wilson <[email protected]> |
| Date: | Fri, 28 Apr 2017 12:36:26 +0100 |
| Dkim-signature: | v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:date:message-id:to:subject:in-reply-to:references:mime-version :content-transfer-encoding; bh=nDvja1B5Dmx4KpDNn7OAoOIlMTdpx2fGxq1NlYXPl+8=; b=htD4zRbr2AKj4d+Dv6vqhV+lq+Cu7s/b0Le9DX/BMSgJO9G528r8i/uv3qFCH7gG81 Nsd5Cis2iUFmQbw1nSS+MRKz5uLsYWVTQggf4UeYdzU37QU9SE+z/S8H2u6gj7AlmlOs 2kCG+0G3WU4EyUqY3k/snlfXoxLDJKK4rl83FNyC6FmXv0U8RsdDkuW/uQhkmnWy18/Q ut1h8tZ6/mADIgnUANjJ9qMqNlQ1ayBCxR53VBz73Yrs+YTqRhnzuNAnqNOD7tfTjc62 sxOkJJQaObjotJE5sE+Z7cyg4YxVf34iztfY5ATGMceQ/i2stvbRq9mJE6NIHExg5Sf+ Xhvw== |
| In-reply-to: | <[email protected]> |
| References: | <[email protected]> <[email protected]> |
| Reply-to: | [email protected] |
| Sender: | [email protected] |
28th May 2017 Hi Stefan, remarkable work on VLF, congratulations!! I see these with all FET's but I acquired very cheaply some Wolfspeed FETs with a lot of overhead. These spikes sometimes kill lesser ones. If you follow these links you can see the normal gate and drain waveforms, and the drain waveform without a Varistor as an OPERA TX period ends, i took the latter from a series of screenshots showing the highest level the close TX spike reaches http://www.gatesgarth.com/wolfspeed-scope-capture-50v.jpg http://www.gatesgarth.com/wolfspeed-overshoot-50v.jpg http://www.gatesgarth.com/wolfspeed.pdf Best regards, Chris 2E0ILY mailto:[email protected] My part time LF grabber is at http://www.chriswilson.tv/grabber.html > Hi Chris, > Which type of FETs are you using? > The IRFP460A for example has a built in Z-diode which seems to handle > the spikes. Anyway i put a 150 Ohm / 220 pF (for LF) series RC paralell > to the Drain-Source... > 73, Stefan -- Best regards, Chris mailto:[email protected] |
| <Prev in Thread] | Current Thread | [Next in Thread> |
|---|---|---|
| ||
| Previous by Date: | Re: VLF: Trace at RC4HAA?, DK7FC |
|---|---|
| Next by Date: | Re: LF: Varistor spike management, DK7FC |
| Previous by Thread: | Re: LF: Varistor spike management, DK7FC |
| Next by Thread: | Re: LF: Varistor spike management, DK7FC |
| Indexes: | [Date] [Thread] [Top] [All Lists] |
