Solid State Guitar Amp Forum | DIY Guitar Amplifiers

Solid State Amplifiers => Amplifier Discussion => Topic started by: jfetter on January 30, 2007, 10:39:33 AM

Title: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jfetter on January 30, 2007, 10:39:33 AM
Anyone have the Orcad 'layout' library for the Pentawatt (TDA2030A and TDA2050). I have the schematic 'Capture' library from ST, no footprints though.

Thanks
 
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jfetter on February 14, 2007, 09:38:42 PM
Here is a footprint for the tda2050V (vertical mnt)
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jfetter on March 03, 2007, 12:29:56 PM
Here is the prototype TDA2050 and jfet preamp. The power amp supplies 24vdc to preamp. Design is single supply +40vdc with an output network that soft clips. The TDA2050 case can be mounted to gnd potential panel. No clipping diodes are in the system.
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: teemuk on March 03, 2007, 12:37:30 PM
Can't see the links...?
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: joecool85 on March 04, 2007, 07:17:28 AM
No links teemuk, he attatched pics.

Looks good btw.
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: teemuk on March 20, 2007, 10:39:35 AM
Well, I can't see the pics either. In none of the threads here. Apparently they show up only on certain software.... maybe I should switch from IE to firefox.
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jfetter on March 20, 2007, 03:01:47 PM
Seems like you have to be logged in to see them. The circuit sounda sweet, now doing a front panel with "Front Panel Designer". I did put one soft diode to pre clip prior to supply running out, so no PS ripple present even at high levels.

I've ordered a Weber 6X9 8ohm to experiment with a 'local' speaker in the head. The test speaker to date has been a Red Fang.

The idea is a compact head that can be used for recording or practice. It will look like a head but is really a combo.

Then add a reverb in next design.
Bruce
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jfetter on April 12, 2007, 11:19:39 PM
Here is the new panel and chassis mock-up.

I picked too large router bit for small text engraving. Also forgot to pick grained finish. It still looks OK. The panel light is a radiio shack neon indicator lens and holder. I removed the neon assy and replaced with a 5,000 mcd 10mm red led. Its just a prototype so I'm trying out new.

Double drilling the panel/chassis is unnecessary by using the open end of the Bud CU-622A.

Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jrc4558 on April 16, 2007, 02:10:22 AM
Great work and cool chassis! Where did you get them?
Also, which program opens the format of the layout you posted earlier?
Looking waaaay cool!
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jfetter on April 16, 2007, 07:51:58 PM
Its a .lib file that is used by Orcad Layout (pcb layout program). If you don't have access to Orcad try eagle
http://www.cadsoftusa.com/freeware.htm

I have not checked but it may actually have the pentawatt pkg in library. The free version is ok for two sided small boards, exactly what ss preamps and poweramps use.

Then send the gerber cad files to http://pcbfabexpress.com/ online.  They are the cheapest fastest no hassle.

The front panel is a free cad program from http://www.frontpanelexpress.com/ , very easy to use and attached is my example. No setup charges and you can buy one , two or production quantities.

unzip the nash20a.zip and open the .fpd file with frontpanelexpress program.
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jfetter on April 29, 2007, 09:11:09 PM
Finally got the head put together. I changed my mind on the clipping diode, took it out. The 6db filter on power amp output serves that purpose just fine and isolates the FB loop from load. So it becomes a partial current source open loop.

Also pictures of my lab bench. Probably looks like everyone elses. Working on the cab/head setup now. BTY the tone ckt is an active muff. The effect pedal is for input ckt saturation testing.
Title: Re: final assy
Post by: jfetter on May 13, 2007, 08:50:43 PM
Here is the final assy, switched to the 'Governor' for grins. The LED gives a brite starr appearance. I used a Geezer cab and mounted as shown with the right angle brackets. The chassis is mounted 0.25" from top of cab to allow air movement. The preamp board(is super quit) has a copper sheet shield but otherwise the chassis is open.

The soud is Fetzer like with very nice asymetrical clipping. Output filter is  -6db at 4000hz and does not allow hard clipping. the tone can scream.
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: joecool85 on May 14, 2007, 07:22:52 AM
You are doing some really great work here!  How does it sound?  And also, you might want to consider adding the schematic(s) to the schematics section here at the forum, I know I would appreciate it.
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jfetter on May 26, 2007, 03:08:16 PM
Two short examples...
Amp is on max volume , center tone and center gain.

1st is on a strat using front pickup.
2nd is on Les Paul with bridge pickup.

The cab has a bad resonance at C# , you can hear it on the low registers( some people like that though) . Have to do some cab work and possibly reduce gain. Mic at aprox 6" in front with a stien e609.

www.avantpower.com/nash20/nash20-320.mp3
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: joecool85 on May 26, 2007, 05:49:14 PM
WOW, that sounds great!  Good guitar skills as well.  Is this schematic posted in the schematics section?  If not, it should be.  I would consider posting it in the wiki as well.  If you don't know how, just ask and I'll help you out.
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jfetter on May 28, 2007, 10:02:06 AM
I'll post the schematic eventually but for now just keep the zine here until perfect.

Found the "vibration". I swept with the function generator and found two points; one at about 100hz and another at 210hz.

The strong 100hz was the front panel! The weaker 210hz was entire chassis box. So I have to rethink the packaging.
The output filter is for sure the way to go on SS amps. We all agreed the unit sounded like a 5E3 Deluxe.

Having Fun with it.
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jrc4558 on June 05, 2007, 02:46:26 PM
Hey everybody! Are the layouts for this amp available anywhere? OR at least schems (i can do pcb myself)...
Thanks in advance! :)
Love the sound of it too!
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: jfetter on June 19, 2007, 10:48:27 PM
I had some pine boards in the garage , so here is the pinebox head, no more vibration.

All ctls at 12:00 on this example of Lenny lead in, no effects ie reverb or anything. I still think I may run the gain down somewhat. The clean to dirty threshold may be too low. not sure yet.



http://www.avantpower.com/nash20/nash20lenny.mp3

Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: joecool85 on June 20, 2007, 08:05:24 AM
Looks absolutely smokin!
Title: Re: Pentawatt layout TDA2030A and TDA2050 etc
Post by: syndromet on June 20, 2007, 08:36:47 AM
Looks great. Good to hear you got rid of the hum