Re: Fireball 40

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From: John J. McDonough (wb8rcr@arrl.net)
Date: Sat Jul 01 2000 - 20:13:52 EDT


Found it!

Apparently the 74LS74's I have are a little soft and can't cut the mustard
into the 0.01uf Cx at 14MHz. I cut traces to use the other 7474 (since only
one is needed for 20) and it was a tad more predictable so I could figure
out what is happening. I reduced Cx and at 180pf the rig worked
intermittently. At 100pf it seems reliable, and there is no 7MHz component,
and the 28MHz component is way down.

72/73 de WB8RCR http://members.home.com/wb8rcr/index.htm
didileydadidah QRP-L #1446 Code Warriors #35


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