12ax7

[pazuzu]

so i have some spare 12ax7's. anyone have any suggestions to a project with layouts i could do with them? i only have one tube socket on hand so preferably a project that only utilizes one. i wanted to make a valvecaster but from what i read this tube wouldn't work.

[petemoore]

  12au7 is a lower gain, that fits where the 12a_7 tube was.
 See data sheets for all the 12a_7 tubes.
 It's all about power supplies and layout, grounding.
 the triodes are otherwise about the same 'get working as wiring as Jfets circuits, higher voltage may mean bigger voltage/wattage ratings on components, it's also dangerous, involves 120vac or 220vac line work at least.
 A 36vdc printer wallwart output is a fun/easy safe place to start with the B+ line, a WW of sufficient current output and a regulator [or other supply method] for the heater.
 12ax7's 'work' but dont provide much gain or become 'lively' with starved plate voltages.
   
 

[igerup]

True, they need a B+ of at least  150 volts. Preferably 200-250, though you can try 300 too if you feel braver than usual. 

[anchovie]

A single 12AX7 with a low-voltage power supply will need a little solid-state help, like with Aron's much-praised Shaka Tube.

[pazuzu]

Aron's much-praised Shaka Tube.

layout? i am sorry, but the layout section is rather confusing for me to navigate. not that i don't understand what i am looking at. i just can't find my way around it.

[frequencycentral]

Shaka: http://www.diystompboxes.com/smfforum/index.php?topic=18369.0

[KazooMan]

Layout and loads of additional information at diyguitarist.com.  Search Shaka Tube

[pazuzu]

thanks a lot! that actually looks pretty easy.