Vacuum tube amplifiers

[efren]

regarding 7193 linestage, these are notorious noise & hum amplifier, even amplifying the mechanical noise of a power transformer if placed in close & not so close proximity, but once this issue is addressed, every one who builds this particular linestage had nothing but positive comments on the sound quality.

 i think i will drop the zener regulator & use cap multiplier instead, with an overkill of capacitance fit for a high power amp., planning also to separate the power supply from the chassis.

chome.omcast.net/~hi-fi/7193.html

[tony]

challenge yan sa skills mo as a builder...

[fantom_mayonaise]

Sir efren : gawa po kayo build thread

[ricdelros]

regarding 7193 linestage, these are notorious noise & hum amplifier, even amplifying the mechanical noise of a power transformer if placed in close & not so close proximity, but once this issue is addressed, every one who builds this particular linestage had nothing but positive comments on the sound quality.

Hwag mo lang kalimutan ang plate choke (small resistor wrap around wire) and bypass the filament with ceramic caps...this may help

[efren]

challenge yan sa skills mo as a builder...

i'll take that challenge sir

Hwag mo lang kalimutan ang plate choke (small resistor wrap around wire) and bypass the filament with ceramic caps...this may help

thanks for the tip sir

Sir efren : gawa po kayo build thread

ok will do that in the hi-fi section

[danny]

depende yan sa application...6H23, 6DJ8, 7DJ8, EC88, PC88, E88C, CCa, 6BK7, 6BQ7, etc...

salamat sir tony
hanap muna ako dito niyang mga iyan.
 +1 sa inyo nila
sir efren at sir alpha

 

[efren]

salamat din sir danny

[danny]

walang anuman sir

[tony]

salamat sir danny...

sharing my tube breadboarding gadget, for octal and 9 pin pin miniatures....can be used to test tubes or for matching parameters:

[efren]

DIY tube tester? galing naman
+1

[tony]

yes in a way...can be used to breadboard circuits, tweaking them prior to actual build...

[ricdelros]

'Found these things in Junk shop...I'm thinking and searching what's the best circuit for this pair of transmitter
 tubes..Datasheet says it can be used for class AB2 audio power amp @ 3000v with plate Output power of 1420 watts.

[tony]

nice find, great tubes, i bet the caps beside those are leaky with age...

[ricdelros]

No problem with my 1978 Diy Capacitor checker...It can determine the cap condition before i put into
assembly.

[efren]

ayos to ah, may revive function din ba ito sir para sa medyo matanda nang e-caps sana may schematic

[ricdelros]

ginawa ko 'to when i was 22 years old at maraming pakinabang...can check condensers and electrolytics of tube amps..forgot already what's inside, pero i'll open-up the hood for you..please wait iguguhit ko pa.

[ricdelros]

"HERE IT IS"




My Novice design in my middle age school..It can practically test capacitors in mirofarads..Resistors in circuit can be changed depends on test voltage you want on electrolytics...Change the value of 0.002 if you find the neon continued to lit at condenser test.

CHECKING CONDENSER :

1. Place the selector switch in neutral position.
2. Clip the condenser under test in the condenser probe.
3. Place the selector sw instantaneously to condenser and watch a single blink of neon for OK.
   Leak or short will continuously lit.
   No Blink is an open circuit.

CHECKING ELECTROLYTIC :

1. Clip the Elect. under test in electrolytic probe.
2. Place the selector switch to Electrolytic position..(Neon will not light when the cap is charging)
   When cap is OK, the neon will lit in a matter of seconds (Time depend on value)
   Neon will remain off if cap is shorted, and neon will not turn off if cap is open.
   Leak can be judged depend on value vs time charged.(if the value is big but charged in a short time,
   that's a leak.)

Device under test will literally trickle,charge,or revive the electrolytic when test, so Discharge the
cap properly with a 20k 2w resistor..Careful of probe clip... ""its live and dangerous.""

  

[Tukkar]

this will help sir...+1 sayo....

BTW, do you have any simple inductance meter schematics?

Does anybody knows how much inductance is present with a 40w flourescent ballast...will it be good to use as inductor on tubes amps...will it pass 0.43 amperes of current as indicated?

[grizzom]

Master sana nailagay to sa isa thread malaki tulong nito lao na sa beginner like me... capacitor tester  hehehe

[ricdelros]

this will help sir...+1 sayo....

BTW, do you have any simple inductance meter schematics?

Does anybody knows how much inductance is present with a 40w flourescent ballast...will it be good to use as inductor on tubes amps...will it pass 0.43 amperes of current as indicated?

Try this site...http://www.doc-diy.net/electronics/l_meter/ Parts are all available