hi,got my hifi interest back after about 20yrs,i kept some of my old gear but sadly sold my Klipch horns...and Pink Triangle,sme turntable..😱
anyway i built a SE 300b amp and stored it in the loft,after removing the valves.
recently got it down and dusted off the thick layers that built up,inside looks fine,but after 20yrs kinda forgot all the specs etc..i built it with help from a Guy called Gary,if i remember,who was from Border patrol,again,if i remember.
It has BP interstage transformers and huge output trans,probably bought from BP,if i remember, and lots of Blackgates,silver wire etc,i spent a fortune on the bits..Looks like it has 2 valve rectified ps's for the interstage tranformers and a modified ps for the main choke input 300b ht,all in seperate enclosures,it weighs a ton..any ideas how i can proceed to get it all running again?
I was pretty good with valves/building when i built it but kinda forgot when i lost interest..
searching for circuits and looks similar to a SJS 108 mk2 amp but mine looks like a 2 stage circuit and didnt write down valves i used,the writing on the valves i kept for it have since lost there numbers🙁 so not sure what they were..
Possibly a long shot to sus out what i built but any help appreciated,retired now so lots of spare time to build etc..
anyway i built a SE 300b amp and stored it in the loft,after removing the valves.
recently got it down and dusted off the thick layers that built up,inside looks fine,but after 20yrs kinda forgot all the specs etc..i built it with help from a Guy called Gary,if i remember,who was from Border patrol,again,if i remember.
It has BP interstage transformers and huge output trans,probably bought from BP,if i remember, and lots of Blackgates,silver wire etc,i spent a fortune on the bits..Looks like it has 2 valve rectified ps's for the interstage tranformers and a modified ps for the main choke input 300b ht,all in seperate enclosures,it weighs a ton..any ideas how i can proceed to get it all running again?
I was pretty good with valves/building when i built it but kinda forgot when i lost interest..
searching for circuits and looks similar to a SJS 108 mk2 amp but mine looks like a 2 stage circuit and didnt write down valves i used,the writing on the valves i kept for it have since lost there numbers🙁 so not sure what they were..
Possibly a long shot to sus out what i built but any help appreciated,retired now so lots of spare time to build etc..
Welcome back!
Please excuse the obvious question, but way back when you built the amp, did you get / follow a schematic?
That would tell you most everything you need know.
Please excuse the obvious question, but way back when you built the amp, did you get / follow a schematic?
That would tell you most everything you need know.
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yes i did have a schematic but unfortunately lost it may yrs ago in a loft clearout..thanks anyway for the reply..
You could upload high resolution pictures from “all” sides (especially the bottom part).
Regards, Gerrit
Regards, Gerrit
thanks,up on further inspection it now looks like a 3 stage amplification before the 300b stage..i will take some pics bit later and try to upload them on here..
possibly based around a BP amp.Wish my memory was better but alot has happened in my life since building it 20yrs ago,but i do remember the superb sound it produced..Struggling posting pics,could be as a new forum member,have another go tomorrow..cheers
I spy with my little eye : a wire with its insulation busted /broken .
(3 'd picture coming of the transformer ) .
I do not know where this wire goes but you might want to fix that and see if the other wires are ok .
Regards F.
(3 'd picture coming of the transformer ) .
I do not know where this wire goes but you might want to fix that and see if the other wires are ok .
Regards F.
yes,thought someone would spot it.lol,its may yrs in the loft,20 hot summers and cold winters that perished the insulation,i think..its the wire from the 300b plate to the output tx..think i'm gunna have to strip it down and make a circuit diagram to try identify what valves i used..i would probably re-chassis it anyway if i rebuilt it up..
well quick update,started stripping it down,starting from the output TX..Suspect a few caps have dried out over many of the storage yrs..make a good autumn/winter project,just too many quality parts used in its build to just forget it..It'll take some time to note down the circuit etc...I built a LM3886 'chip' amp to keep the music flowing in the meantime..LOL.and sounds surprisingly very good..