deltec/DPA schematics

[dan _s]

Hi all
I am looking for schematics for a deltec dpm 1 mkIII digital-analog converter. schematics for any of their other DAC's or preamp will also be helpful.
it for a friend who toasted two tiny transistors on one of the credit card size PCB's.
i searched the web and some discussion groups but havn't found anything.

any help will be appreciated
dan s

 

[13DoW]

DPA Hybrid op-amps

dan_s

the 'credit card' pcb sounds like DPA's hybrid op-amp. This was designed by DPA to out perform off-the-shelf IC op-amps and they used it in most of their products (from MC head amps to the voltage gain stage of power amps).
Debugging one would be difficult as it uses SMT components and testing it might be a challenge because it has a large GBW product.

Perhaps your best bet is to find a working second-hand DPA product and swap out the hybrid boards from that.

Regards
13th Duke of Wymbourne

 

[raul_77]

Hi,

I make the service repair have any years in Spain. I have any schemes of Deltec, if you say to me your needs, and send me a adress of snail mail I can send you any photocopies.

Substitute the opamps for other type is really impossible, perhaps is best think in a new system. Sorry.

Happy days,

Raúl Couto

 

[dan _s]

raul_77 thanks a lot! i'll send you my details
13DoW , thank you for answering, like raul wrote, deltec item are extremely rare, so its either fix or toss

 

[sonytube]

In reply to Raul_77

Hi Raul_77,

Perhaps can you help me with my Deltec PDM series 1.2. I bought it few weeks ago and it sounds "bad" for me, good bass but little medium and no trebble. I checked some caps and everything is OK. I tried to design the circuit diagram by myself but it's definitively to hard because of the two faces printing board and components hiding the circuit. Do you have the circuit diagram of my device ? It will be helpfull for me to check oser components.

I'm not able to reach your email adress because I'm a newby on this forum, so if it's ok for you can you leave me your email adress via a private message ?

Thx,

sonyTube.

 

[ash_dac]

Re: In reply to Raul_77

Hi Raul_77,

Perhaps can you help me with my Deltec PDM series 1.2. I bought it few weeks ago and it sounds "bad" for me, good bass but little medium and no trebble. I checked some caps and everything is OK. I tried to design the circuit diagram by myself but it's definitively to hard because of the two faces printing board and components hiding the circuit. Do you have the circuit diagram of my device ? It will be helpfull for me to check oser components.

I'm not able to reach your email adress because I'm a newby on this forum, so if it's ok for you can you leave me your email adress via a private message ?

Thx,

sonyTube.

My Deltec PDM series 1.2 sounds brilliant!

I seem to remember that one of the complaints with dpa/deltec products is harsh treble due to RFI and poor grounding.

What amplifier are you using ?

 

[sonytube]

Hi Ashley,
Thx for reply!
Your DAC sounds brillant ? That's my problem ;-)

I own a DIY amp tube (hybrid with 4x 6L6 tubes), a tweaked Marantz CD4000 and handmade loudspeakers (Fostex FE207E).

If you are interested, I have some pix.

Sonytube.