Ok, my newborn saw the world for the first time about 5 days ago, and I haven’t finished his first gift 😉
The main idea is to create an active speaker, powered with Quad Amplifier TBA820, onboard MP3 Player, and low voltage tube buffer.
I have finished the Quad Amplifier module as shown below.
I don’t use a real high-end parts, just some parts available on my bin and some newly purchased. Well, I don’t go with premium parts for this small project, but I don’t play cheap anyway.
We can see some quite good parts like Black Gate C Series, Nippon Chemicon KME, and Nichicon Muse BP. The resistor changed from standard carbon to precision metal film. Some ceramics caps remain there.
Below are some other parts will be used for the low voltage tube buffer and power supply section. Luckily I still have enough parts on my bin for this project 😉 Do I see WIMA there?
Custom made power transformer to supply the whole circuit. I need a lot of secondary taps for the Quad Amplifier, the MP3 Player, the tube buffer B+, tube buffer filament, etc. High quality transformer definitely is a must!
The tube buffer module on the PCB. Not yet assembled, just finish the drilling process. It’s nice to have an exact 22 mm holesaw for 9-pin tube socket. Note the unused 2 holes due to wrong drilling process >.<
The tube module from sideview. I’m going to do P2P soldering with the components mounted on the PCB side. Will be looked nice and clean if we can arrange the parts nicely on the top of the PCB.
I think I can finish this in next few weeks 😉
Eric
October 17, 2010 01:56Hi Jimmy,
I’m a big fan. Love the idea of a low power amp for your child. Where did you get the schematic from for this amp. I’m very interested in building it too.
Keep up the fun work,
Eric
Auw Jimmy
October 17, 2010 10:46Hi Eric,
You can find it here:
http://www.radiomuseum.org/tubes/tube_tba820.html
Thanks.
Kasan Santosa
October 20, 2010 09:09OMG… 820 with tube buffer? I can’t wait to hear they sing along…
arie
October 20, 2010 18:08Waaah, congrats Oom Jim atas kelahiran putra pertamanya.. Semoga jadi permata hati bagi keluarga.. Turut berbahagia! Kadonya mantaf jg tuh, emang DIY’er sejati hehe..
Auw Jimmy
October 20, 2010 21:20Thanks Om Arie he he he…
John Starr
October 30, 2010 05:22Hi Jimmy,
Love your site. Do you have Bill Eccher’s email address? I have a Hickok 539C I would like to send to him for repair/restoration
thanks
!
John Starr
October 30, 2010 05:22Hi Jimmy,
Love your site. Do you have Bill Eccher’s email address? I have a Hickok 539C I would like to send to him for repair/restoration
thanks
Auw Jimmy
October 30, 2010 19:34Hi John,
Sorry I dont have his email.
Thanks.
Bill Eccher
December 21, 2010 09:21Hi Jimmy,
I thought you had my email address. I just noticed John Starr was looking for me back in October. Maybe you could send it to him now if he is still interested.
Thanks
Auw Jimmy
December 21, 2010 17:54Hi Bill,
I sent his email to your email, but sorry I didn’t publish it here to avoid any spam.
Thanks.
Greg
November 16, 2014 19:01Hi!
Could you tell us something more about the Quad TBA820 amp? Is it some refined solution for a super stereo or even mono sound, or a return of the quadrophonic sound? 🙂
Googles returned me nothing…
Greetings from Poland,
Greg
Auw Jimmy
December 3, 2014 07:30Hi Greg,
It’s old (or obsolete) chip amp. Not really something special, I believe.
Thanks.