low am pw output help.??

[1iwilly]

hello to all

i have a 148 philly made that on side band i have good power output but on am vr10 wide open=3 1/2 watts swings to 6 on a bird with modulation. driver bias is ok so is final bias
when i check the voltage at the tp 7-8 it is 13.66 volts but when i key the radio it drops down to 6.78 volts is this normal.???
thanks :headbang:headbang:headbang

 

[Shockwave]

Normal AM voltage at test points 7 and 8 should be about half of the full power supply voltage in TX. The 6.78 volts is correct and adjusted by VR-10. On SSB the voltage at these test points will rise up to the full power supply voltage. The output stages (not the 54 Mhz trap) may need alignment to get more power from the radio and not all 148's will produce the same power.

 

[1iwilly]

Normal AM voltage at test points 7 and 8 should be about half of the full power supply voltage in TX. The 6.78 volts is correct and adjusted by VR-10. On SSB the voltage at these test points will rise up to the full power supply voltage. The output stages (not the 54 Mhz trap) may need alignment to get more power from the radio and not all 148's will produce the same power.

thanks but the thing is i re adjusted the bias for 50 and 100 and still the radio
the most i can get out of vr10 wide open is 3 1/2 watts but the final is excellent. ssb i can modualate 15 watts on a bird also there is no trans or resistor clip for modulation but when i try to adjust vr7 with audio it does nothing??? i think r131 is suppose to be 10k but the resistor in mine reads 560 ohms> or maybe it is 56ohms.??i forget the color. if i volt the final from 2 watts dead key i can swing the bird to 10 watts . but audio quality sucks

 

[440denver]

Sounds perfect for an amp!!