Would this be a good all-in-one trans for this circuit?
160V 50VA Toroidal Tube PreAmp Transformer Guitar Amp - eBay (item 250606543894 end time Apr-05-10 21:09:15 PDT)
Looks like the price range I'm hoping for.
160V 50VA Toroidal Tube PreAmp Transformer Guitar Amp - eBay (item 250606543894 end time Apr-05-10 21:09:15 PDT)
Looks like the price range I'm hoping for.
Yes that works, and here is another one for a bit less.
Its small and a different form factor, easy to mount.
Antique Electronic Supply
P-T292
TRANSFORMER, POWER
* 120 V primary
* Secondary 1 - 140 V, 100mA
* Secondary 2 - 28 V, 20mA
* Secondary 3 - 10.5 V, 2A
So there are lot's of options. When you get it hooked up I would like to see a picture.
Keep and eye on the secondary voltage, some of these options will result in a higher B+ on the tube.
A good excersize would be to look up the data sheet for the tube and make sure that you would not exceed the max voltage.
Its small and a different form factor, easy to mount.
Antique Electronic Supply
P-T292
TRANSFORMER, POWER
* 120 V primary
* Secondary 1 - 140 V, 100mA
* Secondary 2 - 28 V, 20mA
* Secondary 3 - 10.5 V, 2A
So there are lot's of options. When you get it hooked up I would like to see a picture.
Keep and eye on the secondary voltage, some of these options will result in a higher B+ on the tube.
A good excersize would be to look up the data sheet for the tube and make sure that you would not exceed the max voltage.
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The 10.5 V AC tap is for the filaments of course, and your 7806 regulator will drop 4.6V so that is about right. Rule of thumb for a 3 terminal regulator is that you want about 3 volts of headroom and what ever the regulator drops in voltage/power is disapated in heat. You also have an extra 28v tap.Hmmmmm what could that be used for?
Very good find. Makes this exercise more in line with what I was trying to accomplish(a cheap tube outout)
I have a few 12vac/500ma transformers. Could I use 2 of these back to back for the high voltage power side; line to 120>12v-12v<120 to bridge rectifier?. I have the trans. and they will fit. Don't wish to make another mistake here.
You can use that system but recognize that it's limited in current. Those are 6 Watt transformers so you can't draw more than that without risk of overheating. Thus, your 120V winding output is limited to 50 mA load.
I was not familiar with those tubes so I looked them up and apparently they are similar to 12AX7. I think plate current on them wouldn't me more than a few mA so you are probably safe. You could draw up to 12 mA per section and I doubt you are running them that high; typical operation would have them drawing less than 1 mA per triode. Just the same, put in a fuse to protect the transformers.
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