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<p><font face="Helvetica, Arial, sans-serif">Hi Everybody,<br>
<br>
I'm in the home stretch with my Codan 4404 400W HFPA project.
This will (hopefully) get me on the air with a little more power
than the barefoot Penelope board :-)<br>
The 4404 amplifier dates from the 1980s where it was part of the
Codan HF4000 series of marine ssb transceivers. <br>
<br>
I have a question about what power output levels I should expect
to see from Penelope.<br>
<br>
At the moment when I press TUN with Tune Power set to 100% and
100% drive I can get a healthy 550mW output from Penelope. This
can comfortably drive my 4404 amplifier to 400W with a 10dB
attenuator in between. The amplifier is not rated at 400W
continuous so I limit these tests :-)<br>
<br>
However, the maximum output I can get on SSB with Penelope (with
Mic input level set so Mic Meter reaches 0dB on voice peaks) is
around 100-120mW peak. With compression I can get it up to
150mW. A TwoTone transmission from the Linearity menu shows
170mW peak. A 100% AM carrier (no modulation) is 80mW.<br>
<br>
The output from the 4404 amplifier with this drive is around
60-80W peak, quite a bit less than what it can achieve. The
input gain the amplifier is adjustable so I can compensate for
the apparent lower SSB output from Penelope if needed.<br>
<br>
Is this significant difference between 550mW 100% tune output
and a 120mW peak SSB voice signal at 0dB mic input what I should
expect to see? <br>
<br>
Regards.<br>
<br>
Michael.<br>
VK5LN/VK5ZEA<br>
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