On 160m it could be the padder caps? for the tune and load caps.? ?On 10m, it could be the plate choke.... and / or? bandswitch contacts.? ?How old is the AL-80B ???
After W8JI left ameritron in 2019, ameritron started winding their own plate chokes. Before that,? W8JI wound all the plate chokes in his shop.? All the chokes wound by ameritron after 2019 are screwed up, with gaps wrong, and? ?too much / too little? q dope slopped down the sides.? Gap at bottom is to close to chassis.? ?Scott has see 8 of em burned up now,,and I know of 4 more.? Some burn up on 10m,? some burn up on 17m, some burn up on 20m.?
CTR eng ( W8JI's new business) sells the real deal 3 x section plate chokes for the ameritron amps.
On 160m padding, check the wiring to the padders carefully.... as they usually wire from cold end of padders to the bandswitch? and use teflon coated wire.....and if the wire is too close to metal, it will arc right through.?
On some of em,? IF using FT-8 mode, and 17m used, the bandswitch contacts get so hot, they actually lose tension, which increases the? resistance even more =? thermal runaway....and the ceramic actually cracks.??
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Lou may well chime in as he has worked on a lot of em.? ?I'll ask scott when I talk to him next, as he has worked on loads of those amps.??
