2950DX lower amps with Modulation

[design4]

Hi All
I have a Ranger 2950DX hooked to a Astron 30Amp PS. Also a TS 350V.
The power supply has a amp meter on it. Lets say with the TS 350V off, when I key the radio with no mod, it does 2.5 to 3 amps. Output watts DK .5-6 on watt meter. And on a field strength meter it is a 1.
When I add mod the the PEP on the watt meter says 25 Watt. But the amp meter on the PS and the meter on the field strength meter swing backwards.
Same with TS 350V on, just more extreme. Watt meter 60DK 250PEP, Amp Meter on PS 20 Amps DK swing down to 12 Amps with Mod. Field strength meter DK 4 Swing down to a 2.
I guess what I am asking is, What could be causing the radio to loose power with Modulation. Saturating the finals ? :headbang

 

[vkrules]

Could be a few things. Sounds like the psu isn't coping. it might be only providing a few amps.Are the volts dropping?.I've also seen the downward swing with an overmodulated am tx.Turn the mic gain down a bit. Try a whistle on ssb.Also rf feeding back to the psu can cause the meter to misread .Are you taking your readings on a dummy load?.

 

[vkrules]

Just read your post again.If the psu can handle 20 amps dk I'm thinking your overmodulated.( most amateur sets can drive the am well into distortion )turn the mic gain down a little at a time and see what its doing. Mark De VK4AAP

 

[design4]

Other Radios do fine. Voltage does not drop. What would cause a radio to use less amperage with mod? According to the field strength meter, also power loss. Just got the radio back from ranger service center!

 

[Shockwave]

If the radio draws less average current when modulated, it definitely is swinging backwards. You should try reducing the carrier until the current remains stable or goes up slightly when modulated. If the carrier is below 4 watts at that point, I would say Ranger did a poor job with the service.