Return to KLUBNL.PL main page
| To: | rsgb_lf_group <[email protected]>, "[email protected]" <[email protected]> |
|---|---|
| Subject: | LF: Re: Elad FDM-DUO on LF |
| From: | Andy Talbot <[email protected]> |
| Date: | Wed, 21 Nov 2018 16:42:45 +0000 |
| Dkim-signature: | v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:from:date:message-id:subject:to; bh=XjveMTfhmuDiBJ9nzU4V2ECouUwnCFl2jb2wkPATkWA=; b=EmD7rydBxa4xPMkqJnzzhYfGw57VVOlCPyqJRxGsKvpP596j+nCcScutmIB4yuyPdt xvLT5dxxlLgp5lWCY82UkRfktV+swyxiuvDSHaJJdjUA2js9qivHrHkHFZ843Ha3GYng 2nHp4SaZ34AUcxbYvvySjR/0cRVb1oi6Vt/Yv1OwHFLocIdg6x1TocH5Yrr4hATpr/4t dXK4t6IcXCvCsKGUB1JgjaTy2sgfEjQAqbKI8IPg+aTKqDmPX/Pn2oDuRA1tXd5rG8dv HaQ8q9ftpjVyPUdqgvu59bL7pAxLAhHk4ELGTLTmrLg6ItL1l8C2cXEeI1jlo8/K5ZEj OtOQ== |
| Reply-to: | [email protected] |
| Sender: | [email protected] |
|
I got an answer from the design team at Elad, including a circuit of the receiver front end, and it looks safe enough. On receiver a PE4283 solid state relay places a short circuit across the transformer feeding the A/D chip. There is also a BAR66 clamp diode at this point, clamping to ~ 1.2V pk-pk max. The BAR66 is a high peak current surge protection device with maximum 1.8 ohm forward resistance at 100MHz, 5mA If using the Rx-2 ant input, there is an additional BAR66 on this. I'd still be happier seeing circuitry that specifically opens the Rx path to the A/D when on transmit, but those clamps and the switched short look good enough. (And the fact teh BAR device is rated to 100MHz suggests its OK for protection at high VHF back-leakage too). Andy |
| <Prev in Thread] | Current Thread | [Next in Thread> |
|---|---|---|
| ||
| Previous by Date: | Re: LF: Copied N1BUG in JT9, Rik Strobbe |
|---|---|
| Next by Date: | Re: LF: Copied N1BUG in JT9, N1BUG |
| Previous by Thread: | LF: Thoughts on SlowJT9 testing, N1BUG |
| Next by Thread: | LF: AWLF Updated 2018-11-21, Alex R7NT |
| Indexes: | [Date] [Thread] [Top] [All Lists] |