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48-475 signal injection
Raleigh
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Posts: 347
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Joined: May 2007
City: Raleigh, NC
#5

09-29-2015, 07:53 PM
Are you injecting your signal through a .1 uF cap? If not capacitively isolated, any DC on your Sig Gen lead could change the grid bias.

But don't ask me why the same thing doesn't happen at point "D". It's a mystery to me.

Everything I've found on line says that the 7C5 is an acceptable substitute for the 7B5 & the specs look similar enough.
John Honeycutt
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Messages In This Thread
48-475 signal injection - by Patrick - 09-27-2015, 02:34 PM
RE: 48-475 signal injection - by Patrick - 09-29-2015, 02:47 PM
RE: 48-475 signal injection - by Radioroslyn - 09-29-2015, 06:11 PM
RE: 48-475 signal injection - by Patrick - 09-29-2015, 06:41 PM
RE: 48-475 signal injection - by Raleigh - 09-29-2015, 07:53 PM
RE: 48-475 signal injection - by Patrick - 09-29-2015, 08:54 PM
RE: 48-475 signal injection - by Raleigh - 10-02-2015, 10:27 PM
RE: 48-475 signal injection - by Patrick - 10-04-2015, 01:00 AM
RE: 48-475 signal injection - by Patrick - 10-09-2015, 02:44 PM
RE: 48-475 signal injection - by Patrick - 10-09-2015, 01:23 PM



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