IC-746 Low Power Output Problem

Author Post

Webmaster

Fri Apr 01 2011, 01:01PM
My IC-746 is only putting out 60 - 80 Watts (depends on band, around 80 watts on 80M decreasing to 60 Watts on 6 metres) into a dummy load in AM of FM mode (unmodulated). This is after turning up the internal power out pots to max. Ive found some reference to this problem via Google search, but due to the passage of time the trail is cold and most links I have found are now broken. As there seems to be reference to this specific problem on the internet, I'm wondering if this is a stock fault and not anything specific to my rig. If anyone knows of this problem and more to the point knows how to cure it, I'd be grateful if you could let me know.

[ Edited Fri Apr 01 2011, 01:03PM ]
Back to top
Trev, EA5ISZ
Fri Apr 01 2011, 03:44PM
Trev, EA5ISZ

Registered Member #13
Joined: Tue Mar 18 2008, 01:43PM

Posts: 143
Certainly in AM I would expect the output to be fairly low, typically around a third of the total pep output Dave. FM would also be lower than the pep output as its a continuous duty mode. I'm surprised see that this rig is specced at 100W all modes. If the SSB output is around 100W I'd say the rig is operating as I would have expected(in fact producing more output than I would have expected in AM/FM) prior to seeing the spec

[ Edited Fri Apr 01 2011, 03:45PM ]
Back to top
Dai, G8FXM
Fri Apr 01 2011, 06:02PM
Webmaster

Registered Member #2
Joined: Mon Mar 17 2008, 06:10PM

Posts: 204
I'd agree if left at factory settings but I've tweeked the internal presets to "max smoke" and I still can't get 100W out of it. But thinking about it as you say AM and FM are probably preset to restrict power in these modes for obvious reasons. So back to my original reason for looking into this, I've never been able to talk this rig up to 100W on SSB. There is a known issue regarding low Mic gain and there are nods for it perhaps this is where the trouble lies.
Back to top
Chris, G3WOS
Sat Apr 02 2011, 08:02AM
Chris, G3WOS
Registered Member #53
Joined: Wed Mar 19 2008, 12:33PM

Posts: 22
I always got just over 100 watts out of my 847 - maybe 105 on 6M Chris
Back to top
Trev, EA5ISZ
Sat Apr 02 2011, 09:08AM
Trev, EA5ISZ

Registered Member #13
Joined: Tue Mar 18 2008, 01:43PM

Posts: 143
The FT847 is specced at just 25 Watts of AM though which is the nub of the original query (apart from the fact its a different radio
Back to top
Trev, EA5ISZ
Sat Apr 02 2011, 09:56AM
Trev, EA5ISZ

Registered Member #13
Joined: Tue Mar 18 2008, 01:43PM

Posts: 143
Dave, I have located a copy of the service manual (not the instruction manual) for the IC746 you are welcome to it if you don't already have a copy. I note by the way that the 746 is specced at 40 Watts of AM rather than the 100 Watts quoted by Rigpix.
Back to top