according to my schematic the 6.3 amp fuse is the heater supply feed for the valve filaments.
the ac through the fuse feeds the heater for the output valves and valve 4 as heater fil1 fil2
the fil1 fil2 then feeds the bridge rectifier br1 rectified to dc and named as fila filb and fed as the...
a wee bit confused
downloaded your schematic and one from schematic heaven and they are drawn differently
but on the schematic heaven one Marshall clearly sets bias voltage at -48 volts and not -40 volts
this may help or hinder the situation
any suggestions cheers
you probably have shorted mosfets (outputs)
solid state can be tricky to work with
you will need a current limiter (bulb) and a variac and a meter.
the problem with solid state is when you have a fault such as this you do not know how much damage is caused and sometimes you have to shotgun...
yes, you are right, forgot to say but (took for granted) that he would know if it holds means - on power up if the fuse does not blow
did not want to complicate the matter by bringing up the dc bridge rectifier
but i think we are saying the same here
cheers
thrawn86 6.3 amps is a lot of amps
i would remove the new power tubes before i replaced the fuse in case there is a heater in one of the new power tubes shorting.
if it holds then replace the new tubes
hope this helps
jon got to clarify this three prong earth thing (you prob know this but just in case)
there is two types of shock in the amp
1 direct contact
2 indirect contact
direct contact occurs when you connect yourself across live and neutral
you take the full current till the nearest fuse upstream...
a disclaimer wont do any harm but wont stop this shit.
the poster starts a thread
how i safely use a 2 prong amp till i change to a three prong.
in the music electronic forum in the last fortnight
then writes his own disclaimer.
fair enough
his credentials - 2 advanced engineering...
brilliant i am going to make one but it wont look as good as this, wordwork is not my strong point
you say it is 5 inches longer
modified spec ?
cost?
any other lessons to pass on cheers
a set of plans are on trinityamps.com site
register / login/forums/
the want adds show a kit made up- this kit is sold out but the resources part of the forum has the plans about 15 pages to download
hope this helps
good post argus tuft
regarding upgrade kit-00021
that would imply that there are upgrade kits 1 to 20 for other marshall upgrades/mods
it would be fantastic if you could start a new thread giving us some info on these if you have it cheers
pulling the power tubes was only to eliminate the possibility of a power tube pulling the heater line down without taking the associated fuse.
you will get no sound until your heaters are working. the receive loop only tests the output section which will not function until the heaters are on...
excellent but thought el34 heaters 2 and 7 (6.3v yes)
i was thinking of the ecc83 twin triode feed (12v dc ie rectified)in this case
been a long day
cheers
ok get the schems from schematic heaven or drtube
download a data sheet for el34 to familiarise yourself with the pins layout
i am assuming that the primary of the transformer has power and that the main fuse is ok
basically the ac heater voltage to the pins of 2 and 7 (4*el34) comes from the...