Richard,
Don't be confused by the manual saying something like "200 watts dc input to
the final" or something like that. The 430 is a 100 watt rig, like most
rigs of it's era.
How are you measuring output power? Not with ssb I hope. Key it down on
cw. If you don't have a code key, use the send button on the front panel.
The 430 also has a current meter.
You may need sighted help for this. Set the meter switch to "IC". Key
down on cw and see how many amps are drawn. At full power it should be
about 17 amps if I remember correctly.
Steve KW3A