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drake l4b

ok linearone, dunno where to start here.
as far as trained to work on high voltage...i guess not trained, and no high voltage gloves either. i am aware of the extreme dangers working with these. not saying that it is wise to do it without, but pretty much guarantee im not the only one that has worked on them without them. (maybe the only one to admit it tho) i do have a draining stick and a safe place to work on it.
as far as replacing tubes without checking them, i just thought that they were bad because they were arcing, i figured that was a dead giveaway, maybe not. the problems were following the 2 tubes that would arc. i do not have a tester, i do know someone that has one as soon as he gets back from a trip. i also just stated that they didnt LOOK bad, you know with black spots or loose pins or signs of arcing. definately not judging by that, just trying to give as much info as possible.
as far as a hamster yes i am amateur extra class, AJ4QG for now, vanity call should be good the 10th KV4D.
as far as resistors i dont think it went out for an unknown reason, when i put the other tubes in it blew it then. very possibly could be another problem that caused it. again just giving the most info i can.
so the reason the finger was pointed at the tubes first was the arcs, then the power supply because of the resistor, and the heat of the power supply. from what i read this is a common problem for aged supplys. the capacitors give out and fail.
no thanks on the xforce or davemade, not my cup of tea. i want one to use on hf, mostly 20-80 meters.
as far as your last post. the reason i was asking about a zg znd z is because i had a chance to get one to test it with. but i decided not to. again was just asking for advice.
however, i am going to get this thing going with or without help from this forum. knowing there are some knowlegeable people here, i thought that they wouldnt mind giving a guy a helping hand. it feels like i got something different than that tho. i do sincerely apologize for bothering you guys with my troubles. i will tuck my tail and go back to the workbench.
 
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dude, I just didnt want to see you throw more good money after bad. I think once you get those tubes tested you will have a much better idea of the problem and where to begin.

I also dont want to see anyone get killed from working on an amplifier. That sucks.
 
she is up and running 100% full output. great amplifier now. shorted tubes was the problem. replaced the resistor in the power supply, caps looked good. will be ordering a rebuild kit from harboughs soon anyway. shorted tube took out the choke on the bottom of the socket too. (hence the glowing tube on power up when high plate voltage "ssb" switch on.) its the small choke that goes to ground. replaced that, replaced resistor, got good tubes and kicking good.
 
Great to hear you got it working! I recently purchased a Drake L4B and luckily this one worked as new from the get-go. However, I plan on purchasing and installing the Harbach PM-400 replacement power supply module in the near future.

Overall it seems to one heck of a work horse and I am very pleased with it.
 

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