[ICOM] 756 Pro III Finals question

[D C Macdonald]

If the amplifier in question is an untuned input
"grounded grid" type amp, converting to a
tuned input circuit may give you all the drive
you need.

Mac, K2GKK/5



----Original Message Follows----
From: Adam Farson <farson at shaw.ca>
Reply-To: ICOM Reflector <icom at mailman.qth.net>
To: 'ICOM Reflector' <icom at mailman.qth.net>
Subject: RE: [ICOM] 756 Pro III Finals question
Date: Thu, 20 Jan 2005 11:36:11 -0800

Hi Kevin,

The PA transistors are 2SC5125's.

I do not recommend increasing the Po of a solid-state RF power amplifier
above the design rating (100W for the Pro3). IMD3 can degrade by as much as
3 dB, and  IMD5 by 5 dB, for every 1 dB increase in Po above the design
rating. There is also a risk of damage to the RF output devices, and to
passive components in the transmitter LPF and the autotuner.

Cheers for now, 73,
Adam VA7OJ/AB4OJ

-----Original Message-----
From: icom-bounces at mailman.qth.net [mailto:icom-bounces at mailman.qth.net] On
Behalf Of Kevin Adam N9IWW
Sent: 20 January 2005 04:53
To: icom at mailman.qth.net
Subject: [ICOM] 756 Pro III Finals question

N9IWW I need the information on the type of finals in The 756 pro 3 please
need to know if I can turn up the output of the radio to drive my amp  I
have older amp that needs 125-130 watts to drive it it's home brew.
Any information would be big help.
  Thank you

N9IWW