Palomar 150A MRF455s X 2

[Switch Kit]

Rolled the dice and nabbed it for 50.00 shipped . Looks all original to me . On high 12 watts in on SSB 125 pep watts all day , low side about 70 . very clean audio on SSB (none of that snap crackle pop crap from class C ) Seems to like 1 watt on AM with about 16 watts pep swing about 30 DK from amp , 125 pep swing . The VSWR's are great through the box as well . Always nice when that section of the amp doesn't need a re-tune . Receive amp 2 db's no problem . Only problem it does have is on the LOW side of AM (not that I need it ) but it does chatter the relays ? (Not on SSB) by the date code on the MRF 455s make this amp 35 years old. Any ideas on that AM low side chatter ? I'm happy all the same as is . Thanks a lot gentleman .

 

[tshows]

Good Evening Switch Kit. I have a 200 A. It has been a great little amp. Got mine back in 2010, paid $55.00 shipped back then. Mine does about 150 to 160 with 12 watts in on SSB, I only run mine on low and have never had a problem on am or SSB. Of course I only talk on AM every blue moon if that often. Take care and have a nice evening.

 

[nomadradio]

Have you checked the SWR in between the radio and the amplifier's Radio jack? Takes a coax jumper and another SWR meter between them.

A chattering relay suggests that the input impedance on low side is too far from 50 ohms. Some designers are fast and loose with the amplifier's input impedance, easy enough to check first.

73