Sires . . . .
Initially . . . .
Sir Martaine . . . . Martaine . . . . . Martaine . . . . My . . .MY . . . .
MY! . . . that creation is being of such ELLE-GUNT construction ! *** . . . . .
I "consume" that the main power switch is being the larger top rocker and that the secondary, lower one . . .kicks another lamp in parallell with the first one.
Only procedurally topping that, would then be going for the whole enchilada in using a rotary switch for the bottom one and making a complete option of switching
1 . . .Two lamps in series for lowest power
2 . . . A sole lamp for medium power
3 . . . Two lamps in parallel for highest power
HEY ! . . . . . Meester Banjo Man
With the
HUMMMING of the transformer . . . that is signifying that any possible inclusion of a thermal fuse being crammed on down within the transformer windings is
STILL good.
MY PRIME FAULT SUSPICIONS WOULD BE . . . .
Is being that one or more of the 2 or 4 discrete power recifier diodes that are configured into either a full wave or full wave bridge rectifier, have shorted its /their junction (s) .
Your pic will only let us see one of their marked designator I.D.'s of its diode . . . as being D?
That one is located just to the right of the top
RED wire coming into
RED J9 push on connection.
Then there is R21 located between it and THEN a like second companion diode .
If 4 diodes are incorporated (FWB) , it would be likely for the other 2 to be located below that set and on down towards the lower
YELLOW C52 ? poly blockcap.
Two of those diodes +/striped / banded leads should end up at the two + ends of the LARGE black E-caps.
Either 1N4007 diodes with their HIGH PIV / breakdown voltage ratings would be better replacements.
Or the optimum would be 1N5007 diodes with both aditional voltage and current cushioning being offered.
( The latter series of physically larger diameter leads, requre a slight reaming out of the pcb holes to accomidate their hefter diameter leads.)
The other LIKELY fault possibility, if this is being an older amp that uses discrete power output transistors . . . .is that circuitry is being direct DC coupled for all but the frontal / initial preamp stage. Therefore there is a good likelyhood of one ? + of the power output transistors crunching from Collector to Emitter and then putting a dead short across your main DC supply. . .
Creating what you are now experiencing. ( Power T- former then say . . . .HUMMMMMMMMMMMM . . . as also, would shorted diodes)
Lastly, if the unit is being new enough, it may be using a "STK" potted power module, that has the same fault inside of it.
If you find that to be, give us its part number for lookup.
**** Except for the visible boo-boo at the very top side of the bottom rocker switch.
Now . . . . ." I got's to knows" . . .a la Dirty Harry . . . . . is the white frontal panel being HARD (Sheet metal) or a softer materiel ?
Thaaaaaaaaaaaassssit . . . . .
73's de Edd . . . . .
I have sexdaily . . . . . . . . no . . .NO . . .NO! . . . I mean dyslexia !
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