What can I make with these?

[docz]

I just found a couple of TIP31 TIP32 transistors, I was thinking maybe I could use them for a power amplifier? Anyone ever tried using those? And anyone who can point me in the direction of a schematic using these that I can study to see if I can use these for guitar purposes?

DocZ

[teemuk]

http://www.rose-hulman.edu/class/ee/hudson/ece351/labs/ECE351Lab5.pdf

[J M Fahey]

http://www.seas.gwu.edu/~ece20/spring01/benfinalreport.pdf
EDIT:  Looks like we posted at the same time, something very similar . Ho Ho Ho  :lmao: :lmao: :lmao:

[docz]

What kind of power can I get out of these?

DocZ

[teemuk]

Approximately 10 watts from first link's design, approximately 7 watts from second link's design.

[docz]

Is there anyway I can get more? Like 50W?

[J M Fahey]

If you need 50W, all right with that, but forget those TIPs you already have, or at most they  could be used as drivers in some bigger amp.
You need the other 99% of parts; mainly the power transformer, supply, chassis and heatsink, not speaking of a proper preamp.
Rather than ask "what can I do with these?" (you already have less than 1 US$ in parts) state what you want and we'll see what to suggest.
Good luck.

[docz]

I have a bunch of other stuff to, I just wondered what I could use them for. I just read that datasheet and they said they were 40W so I thought 10W sounded a bit low. I have a bunch of MPF102, J201, a couple TDA7294, a couple TDA2030, a bunch of op amps 4558D TL072 and LM386, bunch of 2N5401, 2N5551, buckets of 1N4148, 1N4007 a lot of pots, caps, resistors of different values. And I have sockets, plates for chassises, drivers, and a healthy supply of old wall warts from 5 - 16V. The only I don't have is a real deal transformer. But I'm looking for ideas on what I can build from all this stuff. I bought them for some stompboxes I wanted to build, but now that I have built them I have a lot of spare parts and I thought I'd turn some of them into an amplifier. I really want something in the 20 - 100W range I don't know what is possible. But I'm open to suggestions, I guess a 10 - 15W "ruby" or similar would be cool

Doc-Z

[Minion]

Well you got a TDA7294 , there you go , you can get over 50w ....

[J M Fahey]

Well, that's "slightly" different, isn't it?
I'd go step by step
You could make a TDA2030 amp and start by plugging your guitar straight there.
Clean sound anybody?
Then you can make a preamp.
You can use an LM386, any of those funny Fet preamps "based" on famous amps, an MXR Dist+, or even a Guv'nor which by itself is a complete preamp. We are talking garage band levels here.
Later on you can make a TDA7294 amp and upgrade to Club/College band levels.
Then if you have *a lot* of TDA7294's you can make a Faaaaabbulloussssssssssssss Mode Four !!!!!!!!!!!!!!!!!!!!! and burn 4 per week  :lmao: :lmao: :lmao:

[docz]

Cool, ok I just found a transformer. It is certfied for up to 150W, it's got four secondary taps of 12VAC (actually 8 I believe don't know if it is 8 phases of 6V or 12V I will test, it is made to power up four 12V spotlights) @ 4,2A Could this be a candidate for something? Maybe that 50W amp?

DocZ

[J M Fahey]

Nice transformer.
Draw secondary wiring and what you measure, but so far, if you can wire them for 24+24VAC or 48VAC center tapped, which is the same, you can have a nice +/-35VDC supply, ready to power two TDA7294 50W/8r easily.
You can build some sort of "stereo chorus" combo, with 2x12", you'll play anywhere.
I've just repaired a "Ross" 50W, 1x LM3886, +/-35V, one 12" 8r speaker, the thing is LOUD.
You'll have twice as much power.
I write "Ross" V50RG because the thing really is a Korean/Chinese OEM product (inside it says "Belcat 50RG" everywhere, even on the reverb tank and self-made speaker) but wrapped in fake Tweed (really a very good Tolex imitation, even with cloth texture)
I'd build a combo with a 12", an aluminum chassis that later can be easily perforated to add more pots (you can start with a 2 knob amp and end with a 13 knob one), I'd mount inside it the second TDA7294 exclusively driving the extension speaker jack and at will add an extension cab with 1x12".
Then you have a very portable 50W amp, that can grow to 100W, 2x12" when needed.

[docz]

What did you mean "Burn 4 a week"? 4 chips? 4 grand? 4 ears?

DocZ

[docz]

Also about the preamps, will this work as a preamp for that TDA2030 amp? Or will I need something between this circuit and the TDA to get the right impedance?
http://www.erikhansen.net/diy/schematics/misc/2203-RevB.png

DocZ

[J M Fahey]

That preamp sound very good and drives the SS power amp without trouble.
The "4 a week" refers to the infamous Marshall MF4 or Mode Four 350 which uses four TDA7293 kludged into a nightmare power amp, which burns so much that they had to offer little plug-in boards with a TDA7293 each so you can repair it without soldering.
Note: the TDA7293 is an improved version of 7294 with more bells and whistles.
Many technicians refuse to work on them anymore.
Single chip or dual, bridged chip amps are OK; just cool them properly.