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Old September 8th 06, 02:16 PM posted to rec.antiques.radio+phono,rec.radio.amateur.boatanchors,rec.radio.amateur.antenna,rec.radio.amateur.homebrew
Brian Brian is offline
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First recorded activity by RadioBanter: Sep 2006
Posts: 12
Default Curious about the I.R.E. Standard Dummy Antenna

This link seems to be broken.


Pete, I remove temporary items from my web site pretty quickly due to
space restrictions. I tried to e-mail the chart to you but got the
following reply:


----- The following addresses had permanent fatal errors -----

(reason: 591 your host [216.86.143.7] is blacklisted by
bl.spamcop.net. No mail will be accepted)


No more midnight spam for me! Anyway, the chart is back up for a couple
more days.

By the way, on the perfboard I used to build my dummy antenna I added a
0.1 uF coupling capacitor between the signal generator input and a
second output lead with an alligator clip. This provides a 50-ohm
DC-isolated signal for IF alignment. I usually align radio IFs by
sweeping a signal at the front end, often just blasting through the RF
and mixer stages at 455 kHz. But the alligator clip is handy when I
want to drive the mixer grid directly. You can drive the grid with the
dummy network, but the 50-ohm source impedance of the direct output
ensures that the parallel impedance at the grid doesn't affect the
sweep flatness.

Brian