Flex 3000 Output Problem When Connected To Amplifier

K4jns

Ok, new owner of a old flex 3000. I get 100-102 watts out with out the amplifier on in tune mode. Whenever I have the acom 1500 connected in tune mode I only get around 75 to 80 watts of drive. This is plenty of drive, but it looks funny that the drive/tune is 100 watts just to get 75 - 80 watts out. Any ideas would be greatly appreciated. Thanks

Bill -VA3WTB

It sounds like it is not a perfect 50 ohm connection between the radio and amp.

K4jns

My ic7300 would show the same power output with or without the amplifier in standby so I guess that's what is throwing me off? 80 watts of drive would be set at 80 watts to get it not 100 watts to equal 80 watts of drive.

IK8HCG

Try to insert a 75ohm cable long no more than 3ft (1 meter)

K4jns

But why is this different just because of the radio?

IK8HCG

The problem is the amp not the radio. Firstly make this test, load the flex 3000 on a good dummy load without the antenna tuner on and check the right power on each band. When you connect the amplifier do not use the flex antenna tuner On between radio and Amp. If the power drop down respect the test. Try to insert a 75ohm cable.

K4jns

Power out is good on all bands into a dummy load and all my resonant antennas. This is without a tunner. I can see what you mean about the amp tuning input being the problem but wouldn't that do it on any other radio I try it with? It's almost like the flex has a lower overall out put if it's doing it with any radio and I'm having to compensate for it. But still the swr is flat no matter what radio I try driving the amplifier with. On another note is it a problem to run the radio like this? It's pretty much like a safety net because I'll never need more then that power to drive the amplifier anyways.