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From: N1BUG <paul@n1bug.com>
Message-ID: <1c8a9330-43ed-8ff7-2418-58ee935bd883@n1bug.com>
Date: Sun, 24 Dec 2017 11:07:56 -0500
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Subject: Re: LF: TXing 2200m WSPR
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On 12/24/2017 07:40 AM, Andy Talbot wrote:
> Are you sure your 50uH choke is doing its job?

No. I'm not sure of anything! I'm a HF/VHF/UHF and tube amplifier 
guy who decided to get on LF. Working with FETs and ferrite is all 
new to me.

> 9t to get 50uH 
> suggests ferrite witout a gap.  IN which case FDC thought the 
> winding will be saturating the ferrite, driving it into non 
> linearity and reduced L
> 
> Use iron dust or GAPPED ferrite

Yes, I am using ferrite without a gap. I have an iron dust T-106-2 
core available but would have to use rather small enameled wire to 
get the required 61 turns for 50 uH, or else more than one layer of 
winding. I could temporarily borrow a T-157-26 core from another 
project. That would require only 23 turns which would easily fit 
being it's a rather large core.

Unfortunately I now have a rather large amount of ice on the antenna 
and cannot do any more testing. It would appear this ice isn't going 
to melt for at least a week. :(

73,
Paul N1BUG