Last time on Infinite Everest
Guys, Tom Hardy totally steals Peaky Blinders season 2. Fucking nails it.
-I approached the singularity when replacing the cathode coupling resistors with old ones from the original power PCB to my amplifier, dropping the bias voltage from 24v to 14v. This leads me to believe that I have one or more faulty resistors, still. Waiting on compo.
Having received a new matched quad of JJ EL34's from www.tubesandmore.com and el-cheapo Chinese 12AX7 pre's, reattaching the reverb tank leads and panel (just in case) and slapping in the multimeter; 14v on the bias.
SONOFABITCH.
But we haven't faltered yet. After further investigation in to similar issues across a broader spectrum of amplifiers, I will be checking the screen section that is most closely illustrated to the transformer it pulls from.
4:37PM. Sunset redemption.
It becomes apparent that wildly checking values and pointing fingers in all directions is perverted inefficiency.
Guys, Tom Hardy totally steals Peaky Blinders season 2. Fucking nails it.
Productive free time at work translates to a checklist for me to follow whence I return home, running through all power pcb resistors and capacitors before I'm sodomized by the preamp board.
Checklist and eagle-eye suggest replacing a dying star of components. I happened to have some 10K metal-film resistors on hand, so
+replaced R30, R31, R32, R33. (10K)
Looks like all but two of the screen resistors are on my naughty list : 25 and 25-1 seem to be decent christian folk. Also, R23 and R24 are incorrect as far as wattage is concerned; obviously replaced before. That means replacing replacing R23 (220K), R24 (220K), R26 (470K) , R27 (470K), all of which I believe are 1/2 watt or they will be when I'm done. Compo will be arriving in waves. Maybe the traces will stay on the board. Who knows.
R2 tests badish, replacing (50K); R4 tests badish, replacing (100K)
R11, R12, R13, R14: (10ohm / 1watt), replacing due to age.
&Found out the Fluke 117 I use to test components has a diode test mode.
+All power pcb diodes test OK
C4 dissipates to quickly for my inadequate taste; replace it.
Capacitor 14 tests bad by my indifference.
This means I'm to replace both C13 and C14 as I prefer not worrying about one blowing up moments after I finish installing el otro. Also 4 to please the lad.
C10 and C11 reside on the screen; C11 doesn't act right. C10 was marked; replacing the pair. I believe I have these on hand.
Other compo check and clear :
Resistor
3, 5, 6, 7, 8, 9, 10, 15, 16, 17, 18
Capacitor
1, 9, 12, 13, 15, 16, 19, 20, 24, 25
Other news] I found a two and a half page publication regarding the El Diablo, recently acquiring it for a few shillings and a kick in the groin. It will be available in JPG once it arrives.
+replaced R30, R31, R32, R33. (10K)
Looks like all but two of the screen resistors are on my naughty list : 25 and 25-1 seem to be decent christian folk. Also, R23 and R24 are incorrect as far as wattage is concerned; obviously replaced before. That means replacing replacing R23 (220K), R24 (220K), R26 (470K) , R27 (470K), all of which I believe are 1/2 watt or they will be when I'm done. Compo will be arriving in waves. Maybe the traces will stay on the board. Who knows.
R2 tests badish, replacing (50K); R4 tests badish, replacing (100K)
R11, R12, R13, R14: (10ohm / 1watt), replacing due to age.
&Found out the Fluke 117 I use to test components has a diode test mode.
+All power pcb diodes test OK
Capacitor 14 tests bad by my indifference.
This means I'm to replace both C13 and C14 as I prefer not worrying about one blowing up moments after I finish installing el otro. Also 4 to please the lad.
C10 and C11 reside on the screen; C11 doesn't act right. C10 was marked; replacing the pair. I believe I have these on hand.
Other compo check and clear :
Resistor
3, 5, 6, 7, 8, 9, 10, 15, 16, 17, 18
Capacitor
1, 9, 12, 13, 15, 16, 19, 20, 24, 25
Other news] I found a two and a half page publication regarding the El Diablo, recently acquiring it for a few shillings and a kick in the groin. It will be available in JPG once it arrives.
*upcoming posts follow the anatomy of bias pcb and master connector map.
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